UNIVERSITA’ DEGLI STUDI DI PARMAdspace-unipr.cineca.it/bitstream/1889/3809/1/Tesi...

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UNIVERSITA’DEGLISTUDIDIPARMA

Dottoratodiricercain

SCIENZEMEDICHECicloXXXI

Coordinatore:Chiar.moProf.CARLOFERRARITutor:Chiar.moProf.GIOVANNIPASSERI

OSTEOPOROSISANDJAWBONES:

DENTALPANORAMICRADIOGRAPHSTOSCREENFORPOST-

MENOPAUSALOSTEOPOROSISANDCORRELATIONBETWEEN

PERIODONTALSTATUSANDBMD

OSTEOPOROSIEOSSAMASCELLARI:

UTILIZZODIRADIOGRAFIEPANORAMICHEPERESEGUIRESCREENINGDI

OSTEOPOROSIPOSTMENOPAUSALEECORRELAZIONETRASTATUS

PARODONTALEEBMD

Dottorando:FEDERICORIVARA

ANNI2015-2018

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Aimieigenitori,

MarioeElena

“Generapiùspessoconfidenzal'ignoranzadi

quantononfaccialaconoscenza”

-CharlesRobertDarwin-

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ABSTRACT

Osteoporosis is themostcommonchronicbonediseasethatmay interferewithbone

metabolism. This PhD thesis aimed to investigate the effect of osteoporosis on the

jawbones, in particular the relationship between the systemic bone density and the

jawboneconditions.

Firstly, a literature reviewon the effect of osteoporosis on the jawbones and on the

accuracyofpanoramicmorphometricindicestoscreenforreducedbonemineraldensity

werepresented.Despitethepoorqualityoftheavailablestudies,ourdatashowedthat

acorrelationbetween jawboneandskeletaldensity inosteoporoticpatientsmightbe

expected. A second critical review on the correlation between osteoporosis and

periodontalconditionofthepatientsweredone.Similarlytotheaforementionedreview,

despitethequalityofthepapers,acorrelationhasbeensuggested.

Secondly, a clinical trial to compare BMD and jawbones condition in terms of bone

densityandperiodontalstatuswerepresented.Seventypatients,thatweredoneaDxa

scan to investigate the BMD in the previous year, were enrolled and a complete

periodontaldatacollectionaswellasastandardizedortopantomographyweredone.T-

scoresfromtheDxascanwereusedtoclassifypatientsinhealthyorosteoporoticand

specificmorphometricindicesweremeasuredontheOPG.

Finally, a statistical analysis was performed and a significant correlation was found

betweenBMDandacombinationoftwoindices:thequalitative“Klemettiindex”andthe

quantitative“mandibularcorticalwidth”.Theaccuracyofthese indiceswascalculated

andthecombinationshowedahighpredictivevalueindetectinghealthypatients.The

statisticalanalysisappliedtotheperiodontalindicesshowedthatpocketprobingdepth

³ 5 mm and attachment level 3-4 mm were correlated to healthy condition. These

controversial results may be related to the limitations of the study that include the

reducedsamplesizeandtherecruitmentcentre.

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RIASSUNTO

L’osteoporosi è la più comune patologia cronica che influenza il metabolismo osseo.

Questatesididottoratomiraainvestigareglieffettidell’osteoporosisulleossamascellari

einparticolarelarelazionecheintercorretradensitàosseasistemicaelecondizionidel

cavoorale.

Inizialmente, è stata effettuata una revisione della letteratura circa gli effetti

dell’osteoporosi sulle ossa mascellari e riguardo all’accuratezza di specifici indici

morfometricipereffettuarescreeningdiridottadensitàosseaminerale.Nonostantela

modestaqualitàdeglistudiadisposizione,idatidimostranounacorrelazionetradensità

osseasistemicaemascellareneipazientiosteoporotici.Allostessomodo,èstataeseguita

unasecondarevisionecriticasullacorrelazionetraosteoporosiemalattiaparodontale.

Ancheinquestocasounacorrelazioneèstatasuggerita.

Secondariamente,èstatoeseguitountrialclinicopercomparareBMDecondizionidelle

ossamascellariinterminididensitàosseaestatusparodontale.Sonostatireclutati70

pazienticheavevanoeseguitounadensitometriaDxanell’ultimoannoesonostativisitati

per ottenere le informazioni relative allo stato parodontale oltre ad una

ortopantomografiastandardizzata.Specificiindicimorfometricisonostatimisuratisulla

radiografiapanoramica.

Inultimo,unacorrelazionestatisticamentesignificativaèstatadimostratatrailBMDe

unacombinazionedidueindicipanoramici:ilqualitativo“Klemettiindex”eilquantitativo

“mandibular cortical widht”. È stata calcolata l’accuratezza di questi indici e la

combinazionedeiduehamostratounaltovalorepredittivonell’identificarepazientisani.

L’analisi statistica applicata agli indici parodontali ha mostrato una correlazione di

profonditàdisondaggiomaggioredi5mmeunaperditadiattaccoclinicodi3-4mmcon

lacondizionedipazientesano.Questirisultaticontroversipossonoesserecollegatialle

limitazioni dello studio come la numerosità del campioneo il bias legato al centro di

reclutamento.

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TABLEOFCONTENTS

ABSTRACT

RIASSUNTO

TABLEOFTABLES

TABLEOFFIGURES

1 INTRODUCTION............................................................................................................12

1.1 OSTEOPOROSIS.........................................................................................................13

1.1.1 DEFINITION.......................................................................................................13

1.1.2 DIAGNOSIS........................................................................................................13

1.1.3 CLASSIFICATION................................................................................................15

1.1.4 EPIDEMIOLOGY................................................................................................17

1.1.4.1 EUROPE...................................................................................................................................17

1.1.4.2 ITALY........................................................................................................................................18

1.1.5 PATHOGENESIS.................................................................................................19

1.1.6 RISKFACTORS...................................................................................................22

1.2 PERIODONTALDISEASE.............................................................................................23

1.2.1 DEFINITION.......................................................................................................23

1.2.1.1 ANATOMYOFTHEPERIODONTALTISSUES.............................................................................23

1.2.1.1.1 Gingiva–macroscopicanatomy..........................................................................24

1.2.1.1.2 Gingiva–microscopicanatomy...........................................................................25

1.2.1.1.3 Periodontalligament...........................................................................................27

1.2.1.1.4 Rootcementum...................................................................................................28

1.2.1.1.5 Alveolarbone......................................................................................................29

1.2.1.1.6 Bloodsupplyoftheperiodontium.......................................................................30

1.2.1.1.7 Lymphaticsystemoftheperiodontium..............................................................31

1.2.1.1.8 Nervesoftheperiodontium................................................................................33

1.2.1.2 FEATURESOFPERIODONTALDISEASE....................................................................................34

1.2.1.3 EXAMINATIONMETHODS.......................................................................................................35

1.2.1.3.1 Inflammationassessment....................................................................................36

1.2.1.3.2 Periodontalsupportassessment.........................................................................37

1.2.1.3.3 Radiographicevaluation......................................................................................40

1.2.2 DIAGNOSISOFPERIODONTALDISEASE............................................................40

1.2.3 CLASSIFICATIONOFPERIODONTALDISEASE....................................................41

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1.2.3.1 GINGIVALDISEASE...................................................................................................................42

1.2.3.2 CHRONICPERIODONTITIS........................................................................................................43

1.2.3.3 AGGRESSIVEPERIODONTITIS..................................................................................................44

1.2.3.4 PERIODONTALDISEASEASARISKFORSYSTEMICDISEASE.....................................................45

1.2.3.5 NECROTIZINGPERIODONTALDISEASE....................................................................................46

1.2.3.6 ABSCESSESOFTHEPERIODONTIUM.......................................................................................47

1.2.3.7 PERIODONTITISASSOCIATEDWITHENDODONTICLESIONS...................................................47

1.2.4 EPIDEMIOLOGYOFPERIODONTALDISEASE.....................................................48

1.2.4.1 Prevalenceofperiodontaldisease..........................................................................................48

1.2.5 ETIOPATHOGENESISOFPERIODONTALDISEASE..............................................50

1.2.5.1 MICROBIALETIOLOGY.............................................................................................................50

1.2.5.1.1 Dentalplaqueandthebiofilmconcept...............................................................50

1.2.5.1.2 Plaque-formationmechanism.............................................................................51

1.2.5.1.3 Dentalcalculus....................................................................................................53

1.2.5.1.4 Periodontalpathogens........................................................................................53

1.2.5.1.5 Themicrobialcomplexes.....................................................................................55

1.2.5.2 PATHOGENESISOFPERIODONTALDISEASE............................................................................57

1.2.6 RISKFACTORSFORPERIODONTITIS.................................................................61

1.2.6.1 NON-MODIFIABLERISKFACTORS............................................................................................62

1.2.6.1.1 Age.......................................................................................................................62

1.2.6.1.2 GenePolymorphisms...........................................................................................62

1.2.6.2 MODIFIABLEENVIRONMENTAL,AQUIREDANDBEHAVIORALFACTORS................................63

1.2.6.2.1 Specificmicrobiota..............................................................................................63

1.2.6.2.2 Smoking...............................................................................................................63

1.2.6.2.3 DiabetesMellitus.................................................................................................64

1.2.6.2.4 Obesity................................................................................................................65

1.2.7 PERIODONTITISANDOSTEOPOROSIS..............................................................65

1.3 OSTEOPOROSISANDJAWBONES..............................................................................67

1.3.1 SYSTEMICANDJAWBONELOSS......................................................................67

2 HYPOTHESISANDAIMOFTHERESEARCH….................................................................70

2.1 BACKGROUNDANDHYPOTHESIS..............................................................................71

2.2 AIMOFTHESTUDY....................................................................................................72

2.2.1 PRELIMINARYLITERATUREREVIEWS................................................................72

2.2.2 PRIMARYOUTCOMES.......................................................................................72

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2.2.3 SECONDARYOUTCOMES..................................................................................73

3 LITERATUREREVIEWS…………………………………...............................................................74

3.1 SYSTEMICMINERALBONEDENSITYANDJAWBONES...............................................75

3.2 PERIODONTITISANDOSTEOPOROSIS.......................................................................82

4 CLINICALSTUDYDESIGN…………………………………………………………………………………………….86

4.1 OVERALLSTUDYPLAN...............................................................................................87

4.2 INCLUSIONCRITERIA.................................................................................................88

4.3 EXCLUSIONCRITERIA.................................................................................................88

4.4 STUDYVISITS.............................................................................................................89

4.5 STUDYMEASUREMENTS...........................................................................................89

4.5.1 Dentalpanoramicradiographs.........................................................................89

4.5.2 PeriodontalExaminations................................................................................90

4.6 STATISTICALPROCEDURES........................................................................................91

4.6.1 Samplesizeestimation.....................................................................................91

4.6.2 Statisticalmethod............................................................................................91

5 RESULTS…………………………………………………….................................................................92

5.1 GENERALANDDEMOGRAPHICDATA........................................................................93

5.2 OPGINDICESANDOSTEOPOROSISDATA..................................................................93

5.3 PERIODONTALDATA.................................................................................................98

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6 DISCUSSION…………………………………………….................................................................116

6.1 PANORAMICMORPHOMETRICINDICESFORDETECTINGREDUCEDBMD..............117

6.2 PERIODONTALEXAMINATIONDATAANDBMD......................................................120

6.3 SAMPLESIZEANDRECRUITMENTPATTERN............................................................123

6.4 CONFUNDINGFACTORS..........................................................................................124

6.4.1 Age.................................................................................................................124

6.4.2 Smoke.............................................................................................................124

6.4.3 Medications....................................................................................................125

7 CONCLUSIONS………………………………………………………………………………………………………….126

8 REFERENCES…………………………………………….................................................................129

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TABLEOFTABLES

Tab.1WHOOperationalDefinitionofOsteoporosisbasedonBMDmeasurement....................13

Tab.2Conditions,diseasesandmedicationsthatcauseorcontributetoosteoporosisand

fractures(from(Clinician’sguidetopreventionandtreatmentofosteoporosis2014).....16

Tab.3Searchstrategy....................................................................................................................76

Tab.4Papersincludedinthereview(2014-2018)........................................................................81

Tab.5Searchstrategy....................................................................................................................82

Tab.6Papersincludedinthereview.............................................................................................85

Tab.7Klemettiindexaccuracy.......................................................................................................95

Tab.8MCWROC-areaunderthecurvedata...............................................................................95

Tab.9Mandibularcorticalwidthindexaccuracy..........................................................................95

Tab.10AccuracyofKIinassociationwithMCWwhenrelatedtot-scores..................................97

Tab.11Accuracyofpanoramicmandibularindex,Mentalratio,antegonialindexandgonial

index.......................................................................................................................................98

Tab.12Pocketprobingdepth(PPD)statisticalanalysis:medianand1stquartile.......................99

Tab.13Clinicalattachmentloss(CAL)statisticalanalysis:averageandstandarddeviation.....101

Tab.14Toothlossstatisticalanalysis:medianand1stquartile..................................................102

Tab.15Recession(REC)andtoothmobility:medianand1stquartile.......................................102

Tab.16Demographicdatacollection.Age,etnicity,smoke,height,weight,bmiandmedications

havebeenrecorded.............................................................................................................105

Tab.17T-scoresanddiagnosticclassificationinhealty,osteopenicandosteoporotic.Healthy

andosteopenicpatientshavebeenclassifiedas"0"andosteoporoticas"1"..................108

Tab.18Panoramicmorphometricindices:Klemettiindex,mandibularcorticalwidth(MCW),

panoramicmandibularindex(PMI),mentalratio(M/M),antegonialindex(AI),gonialindex

(GI)........................................................................................................................................111

Tab.19Periodontaldatacollection:Number/percentageofteethloss,percentageofteethwith

augmentedmobility,furcationinvolvement,percentageofsiteswithpockedprobing

depth(PPD),recession(REC)andclinicalattachmentlevel(AL)........................................115

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TABLEOFFIGURES

Fig.1Bonemassmodificationandbehaviorovertime................................................................20

Fig.2Bonemassresorptionrateinwomen(left)andmen(right)...............................................21

Fig.3Theperiodontium:gingiva(G),peridontalligament(PL),rootcementum(RC),alveolarbone

proper(APB),alveolarprocess(AP)......................................................................................23

Fig.4Threepartsofthegigngiva:freegingiva(FG)thatfinishesatthecemento-enameljunction

(CEJ),interdentalgingiva,attachedgingiva(AG).Thedemarcationlineisthemuco-gingival

junction(MCJ)........................................................................................................................25

Fig.5Theschematicdrawingofthehistologicsectiondescribingthecompositionofthegingiva

andthecontactareabetweenthegingivaandtheenamel.................................................27

Fig.6Schematicdrawofperiodontalligamentwithfibersorientation:alveolarboneproper(ABP),

rootcementum(RC),alveolarcrestfibers(ACF),horizontalfibers(HF),obliquefibers(OF)

andapicalfibers(APF)...........................................................................................................28

Fig.7Vertical sections throughvarious regionsofmandibulardentition.Thebonewall at the

buccal(B)andlingual(L)aspect............................................................................................30

Fig. 8 The schematic draw of the blood supply to the teeth and the periodontal tissues: the

intraseptalartery(B),periodontalligamentartery(A)andsupraperiostealvessels(C).....31

Fig.9Schematicdrawof the lymphaticsystem: Jagulodigastricnode (JD),deepcervicalnodes

(CP),sub-mandibularnodes(SMA)andsubmentalnodes(SME)........................................32

Fig.9Schematicdrawoftheinnervationofthejaws...................................................................34

Fig.11Probingdepthinacompromised(left)andhealty(right)peridontalpocket...................35

Fig.12Differentdegreesofinflammationinaperiodontaltissue................................................37

Fig.12Furcationsounding:TheNabersprobeentersthefurcationaccordingtohorizontalthe

bonedestruction(F1,F2,F3,left).Thegradingofverticalboneresorption:AifF<3mm,Bif

3mm<F<6mm,CifF>6mm(right)..........................................................................................39

Fig.14Toothmobilityassessment.................................................................................................39

Fig.15Completeapico-periapicalstatus.......................................................................................40

Fig.16Schematicrepresentationofthedifferentstagesintheformationofdentalbiofilms.a)

Pellicleformsonacleantoothsurface.Bacteriaaretransportedpassivelytothesurface.b)

attachment becomes more permanent through specific stereochimical molecular

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interactionsbetweenbacteriumandpellicleandsecondarycolonizersattachtothealready

attachedprimarycolonizers.C)growthresultsinbiofilmmaturation................................52

Fig.17a)Associationamongsubgingivalspecies.Thedifferentcolorsinthepyramidrepresent

different bacterial complexes which are frequently detected in association with one

another. The base of the pyramid represents the early stage of plaque development,

whereas the apex contains those organisms thought to be the last species to become

establishedinthemicrobiota.b)PiechartsofthemeanpercentageDNAcountofmicrobial

groupsinsupragingivalplaque..............................................................................................57

Fig. 18 Classical model of Page & Kornman, showing host–microbeinteractions in the

pathogenesisofperiodontitis.LPS, lipopolysaccharide;MMPs,matrixmetalloproteinases;

PMNs,polymorphonuclearneutrophils................................................................................58

Fig.19Contemporarymodelofhost–microbeinteractionsinthepathogenesisofperiodontitis,

inwhich the host response drives an incipient dysbiosis (gingivitis). If the biofilm is not

disrupted/removed, frank dysbiosis results and perpetuates a chronic nonresolving and

destructive inflammation. DAMPs, damage-associated molecular patterns; fMLP, N-

formylmethionyl-leucyl-phenylalanine; GCF, gingival crevicular fluid; LPS,

lipopolysaccharide; MMPs, matrix metalloproteinases; PMNs, polymorphonuclear

neutrophils.............................................................................................................................60

Fig.20A)Quantitativeindices:MCW=b;PMI=b/a;GI=d;AI=e;M/M=c/a...............................69

Fig.21Numberofarticleperyearfrom1949to2018..................................................................83

Fig.22MandibularcorticalwidthROCcurve.................................................................................96

Fig.23PMI,M/M,AI,GIROCcurve...............................................................................................97

Fig.24ScatterplotrepresentingthedistributionofthesiteswithaPPD³5mminrespectoft-

scoresasacontinuousvariable...........................................................................................100

Fig.25ScatterplotrepresentingthedistributionofthesiteswithaAL3-4mminrespectoft-

scoresasacontinuousvariable...........................................................................................101

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1 INTRODUCTION

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1.1 OSTEOPOROSIS

1.1.1 DEFINITIONOsteoporosis is a “systemic skeletal disease characterized by low bone mass and

microarchitectural deterioration of bone tissue, with a consequent increase in bone

fragilityandsusceptibilitytofracture”(1).Itisconsideredasa“silent”disease,whichis

often diagnosed belatedly, since most of the times it is not associated with clinical

manifestations until a fracture occurs (2). Osteoporotic fractures normally involve

weight-bearing portions of the skeleton such as spine, proximal femur andwrist and

developasaconsequenceoffallsorlow-impacttraumaorevenspontaneously.(3).

1.1.2 DIAGNOSIS

The diagnosis of densitometric osteoporosis is related to the measurement of bone

mineraldensity(BMD),whichiscommonlydefinedinrelationtoaT-orZ-score,bothof

whichareunitsofstandarddeviation(SD).TheT-scoredescribesthenumberofSDsby

whichtheBMDrecordedinthesinglepatientdiffersfromthemeanvalueexpectedin

youngwhitehealthyfemales,whilsttheZ-scoredefinesthenumberofSDsbywhichthe

BMDrecordeddiffersfromthemeanvalueexpectedforpeopleofthesameageandsex.

TheWorldHealthOrganization (WHO)definesosteoporosis as a T score2.5ormore

belowtheyoung femaleadultmean (4-6),whileosteopeniacorresponds toaTscore

between-1and-2.5.Tab.1

Classification Tscore

Normal ≥-1

Osteopenia -1<T>2.5

Osteoporosis ≤-2.5

Severeorestablishedosteoporosis ≤-2.5+oneormorefractures

Tab.1WHOOperationalDefinitionofOsteoporosisbasedonBMDmeasurement

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TheNationalHealthandNutritionExaminationSurvey(NHANES)IIIdatabaseoffemoral

neckBMDmeasurementsinwhitewomenaged20-29years(7)hasbeenrecommended

byWHO, IOF, ISCD and NOF as the reference database for calculating T-scores and,

therefore,thefemoralneckhasbecomethereferencesiteforosteoporosisdiagnosis(8).

Some guidelines promoted the evaluation of BMD at both hip and lumbar spine and

suggestedtoconsiderthelowerofthetwovaluestoplaceadiagnosisofosteoporosis

(9), although the use of multiple sites does not seem to improve the prediction of

fractures(10,11)

SeveraltechniqueshavebeenadoptedforBMDmeasurement(singleanddualphoton

absorptiometry,quantitativecomputedtomography,quantitativeultrasound,etc),but

themostvalidatedoneisdualenergyX-rayabsorptiometry(DXA),owingtothesensitivity

ofX-raysabsorptionto thebonecalciumcontentandthe trivialamountof radiations

delivered (12).When it is impossible tomeasure/interpretBMDat thehipor lumbar

spine, it is advisable to consider the 33% distal radius (one third of the radius) as

referencesite(13).

Althoughthehipandlumbarspinearebyfarthemostwidelyusedsitesforthediagnosis

of osteoporosis, other sites are sometimes evaluated to measure BMD, such as the

calcaneus, the phalanx and the radius. Several studies have also tried to measure

jawbonemineraldensityandtocorrelateitwiththedensityatotherskeletalsites(see

chapter1.3).

ScreeningprogramsforosteoporosisdifferbetweenCountries.TheWHOreports that

thereisindirectevidencesupportingscreeningprogramsinwomenaged65orolder,but

nodirectevidencesupportswidespreadscreeningprograms(14)andoverallthisideais

not feasible incountry like Italydueto the largenumberofpotentialpatientandthe

limitsofnationalhealthcaresystem.TheNationalOsteoporosisFoundation(NOF)and

International Society for Clinical Densitometry (ISCD) (15) recommend bone

densitometryfor:

- womenaged65andolderandmenaged70andolder

15

- post-menopausalwomenandmenolderthan50yearsbasedontheriskfactor

profile

- post-menopausalwomen andmenolder than 50 yearswhohad an adult age

fracture,withtheaimtodiagnoseanddeterminethedegreeofosteoporosis.

Adifferent approach is suggestedby theUKNational Institute forHealth andClinical

Excellence (NICE) (https://www.nice.org.uk/guidance/cg146), which recommends the

following:

- donotroutinelymeasureBMDtoassessfractureriskwithoutpriorassessingit

withFracturedRiskAssessment(FRAX)toolorQFracture

- considerfractureriskassessmentinallwomenaged65andolderandmenaged

75andolder

- considerfractureriskassessmentinwomenagedunder65yearsandmenaged

under75yearsinthepresenceofriskfactors

- donotroutinelyassesstheriskinpeopleyoungerthan50years,unlesstheyhave

majorriskfactors

- followingriskassessmentwithFRAX(withoutaBMDvalue)orQFracture,consider

measuringBMDwithDXA in peoplewhose fracture risk is in the regionof an

intervention threshold foraproposed treatment,and recalculateabsolute risk

usingFRAXwiththeBMDvalue.

InItaly,theapproachconsiderstheBMDevaluationforwomenandmenaged6570and

olderorinwomenandmenagedunder65inthepresenceofriskfactors

1.1.3 CLASSIFICATION

Traditionally,twotypesofosteoporosishavebeendistinguished:primaryandsecondary

osteoporosis:

- Primaryosteoporosis isaconditionthatdoesnotdevelopasaconsequenceof

concomitantdiseases and includespost-menopausal osteoporosis (type1) and

senileosteoporosis(type2).

16

Secondaryosteoporosis iscausedbycertainconcomitantdiseasesormedicationsthat

affectbonemetabolismandbonemineraldensity.Tab.2

Tab.2Conditions,diseasesandmedicationsthatcauseorcontributetoosteoporosisandfractures(from(Clinician’s

guidetopreventionandtreatmentofosteoporosis2014).

However,thisdistinctionwasmeaningfulwhenlittlewasknownaboutosteoporosisand

mostofthecasesweredefinedas“primary”simplybecausetheunderlyingcauseswere

unknown.Nowadays,thisdistinctionisconsideredsimplisticandnolongersatisfactory

HypogonadalstatesAndrogeninsensitivity Anorexianervosa AthleticamenorrheaHyperprolactinemia Panhypopituitarism Prematuremenopause(<40yrs)EndocrinedisordersCentralobesity Cushing’ssyndrome Diabetesmellitus(type1&2)Hyperparathyroidism Thyrotoxicosis Gastrointestinaldisorders

Celiacdisease Gastricbypass GastrointestinalsurgeryInflammatoryboweldisease Malabsorption PancreaticdiseasePrimarybiliarycirrhosis HematologicdisordersHaemophilia Leukaemiaandlymphomas MonoclonalgammopathiesMultiplemyeloma Sicklecelldisease SystemicmastocytosisThalassemia RheumatologicandimmunediseasesAnkylosingspondylitis OtherrheumaticandautoimmunediseasesRheumatoidarthritis Systemiclupus NeurologicalandmusculoskeletalriskfactorsEpilepsy Multiplesclerosis MusculardystrophyParkinson’sdisease Spinalcordinjury StrokeMiscellaneousconditionsanddiseasesAIDS/HIV Alcoholism AmyloidosisChronicmetabolicacidosis Chronicobstructivelungdisease CongestiveheartfailureDepression Endstagerenaldisease HypercalciuriaIdiopathicscoliosis Post-transplantbonedisease SarcoidosisWeightloss MedicationsAluminium(inantacids) Anticoagulants(heparin) AnticonvulsantsAromataseinhibitors Barbiturates CancerchemotherapeuticdrugsDepo-medroxyprogesterone(premenopausalcontraception)

Glucocorticoids (≥5 mg/dprednisoneorequivalentfor≥3months)

GnRH (Gonodotropin releasinghormone)agonists

Lithium Cyclosporine A andtacrolimus

Methotrexate Parentalnutrition

Protonpumpsinhibitors Selective serotonin reuptakeinhibitors

Tamoxifen(premenopausaluse)

Thiazolidinediones (such asActos®andAvandia®)

Thyroidhormones(inexcess)

17

(16).Asignificativeamountofthecasesofosteoporosis,especiallyinmales,cannowbe

ascribedtodifferentriskfactors(suchasoestrogendeficiency,corticosteroidtherapyor

hypogonadism)actingatdifferentlevelsincausingboneloss(16).Moreover,in1998the

type1and2ofprimaryosteoporosiswerereviewedandsincethenthe“unitarymodel

of osteoporosis in postmenopausal women and ageing men” has been applied (17).

Accordingtothismodel,oestrogendeficiencyistheleadingcauseofbonelossinwomen

butgivesalsoamajorcontributionintheslowandcontinuousbonelossexperiencedalso

byelderlymen(18).

1.1.4 EPIDEMIOLOGY

1.1.4.1 EUROPE

In2010,itwasestimatedthatosteoporosishadaprevalenceof27.6millioninEurope

(22millionwomenand5.6millionmen),with3.5millionnewfragilityfracturesrecorded

and related to osteoporosis. These data are expected to significantly increase in the

future,owingtopopulationgrowthandageing(19).Theprevalenceofosteoporosisis

the highest in Whites (or Caucasians) and the lowest in US Blacks, while Mexican-

Americans fall in between the two groups (16). Approximately one in two Caucasian

womenandoneinfivemenareexpectedtoexperienceanosteoporosis-relatedfracture

withintheirlifetime(20).

Thesitesmosttypicallyaffectedbyosteoporoticfracturesarevertebralbodies,proximal

femur, proximal homerus and distal radius (19). The hip (proximal femur) fracture is

consideredthemostseriousone,sinceitalmostalwaysrequireshospitalizationanditis

associatedwithahighmorbidity(60%ofpatientsshowdifficultiesinatleastoneessential

dailylifeactivityafteroneyear(21)andhighmortality(24%ofpatientsdiewithinthe

first year (22). Osteoporosis-related fractures have been related to more disability-

adjustedlife-years(DALYs)lostthananytypeofcancer,withtheexceptionoflungcancer

and account for 0.83% of the worldwide burden associated with non-communicable

diseases (23). In 2010 estimated the economic cost related to osteoporotic fracture

18

treatment,long-termcareandpharmaceuticalpreventioninEuropeequivalentto€26

billions,€11billionsand€2billions,respectively.

1.1.4.2 ITALY

In a 2013 country-specific report of the ministry of health on epidemiology of the

osteoporosis,theItalianpopulationatriskofosteoporosiswasconsideredtoincludemen

andwomen≥50years.Thenumberofmenandwomen≥50yearsofageamountedto

10,791,000and12,997,000respectivelyinItalyin2010.

Inthepopulationatrisk,thenumberofindividualswithosteoporosis—asdefinedbythe

WHOdiagnosticcriteria—wasestimatedat3,790,000.Thenumberofincidentfractures

in 2010 was estimated at 465,000. Incident hip, clinical spine, forearm and “other”

fractureswereestimatedat91,000,71,000,72,000and232,000respectively.69%of

fracturesoccurred inwomen. In thepopulationover 50 years of age, thenumberof

individualswithhipandvertebralfracturesthatoccurredbefore2010wasestimatedat

517,000and539,000respectively.Moreover,thenumberofcausallyrelateddeathsin

2010was estimated at 5,476 and, overall, approximately 53%of deaths occurred in

women,confirmingtherelativemoreelevatedriskinosteoporoticmales.Regardingthe

economicincidenceinItaly,thecostofosteoporosisin2010wasconsideredtoconsist

ofthreecomponents:

- costoffracturesthatoccurredin2010(“firstyearcosts”)

- costoffracturessustainedpriortoyear2010butwhichstillincurredcostsin2010

(“long-termdisabilitycost”)

- cost of pharmacological fracture prevention including administration and

monitoringcosts(“pharmacologicalfracturepreventioncosts”).

The cost of osteoporosis in 2010 was estimated at € 7,032 million. First year costs,

subsequent year costs and pharmacological fracture prevention costs amounted to €

4,269million,€2,402millionand€361millionrespectively.

19

Accordingtothisreport,thepopulationabove50yearsofageisexpectedtoincrease

from23.8millionin2010to29.2millionin2025,correspondingtoanincreaseof23%.

Thetotalnumberoffractureswasestimatedtorisefrom465,000in2010to598,000in

2025,correspondingtoanincreaseof28%.

1.1.5 PATHOGENESIS

Itisintuitivetounderstandthatwheneveradiseasecausesboneloss,thismustbedue

toanimbalanceinbonemetabolism,betweentheanabolicprocessofboneformation

and the catabolic process of bone resorption. Following an increase throughout the

puberty,bonemasspeaksclosetotheendofthethirddecadeoflife,afterwhichaslow

and progressive phase of bone loss begins. Studies utilising quantitative computed

tomography(QCT)havedemonstratedadifferentbehaviourofcorticalandtrabecular

bonedensityacrosstime(Fig.1).ThecorticalBMDtendstoremainstableuntilmid-life

andstartsdecreasingsignificantlywithageing(inassociationwithsexsteroiddeficiency).

Onthecontrary,trabecularBMDbeginstoslowlydecreasealreadyduringadulthoodand

continues throughout life, thus suggestinganoestrogen-independentcomponent (24,

25).

20

Fig.1Bonemassmodificationandbehaviorovertime

Themostcriticaleventforwomen’sbonemassisundoubtedlythecessationofovarian

functionatmenopause.Typically,atmenopausethereisaninitialrapidphaseofbone

loss(2-4%ofBMDratedeclineayear)thatlastsforthefirst7-10years.Duringthistime,

BMDmayreduceinsomewomenupto25-33%,ifnotpreventedbyaspecifictherapy

abletoreducebone loss, (ie,bisphosphonates,anti rank-LAb,oestrogenorhormone

replacementtherapy).Afterwards,bonelosscontinuesataslowerpace(approximately

1-2%BMDdeclineayear)fortheremaininglifetime(17,26-29).Intheearlyphase,BMD

loss involves mainly the cancellous bone and it seems to be triggered by oestrogen

withdrawaland itssubsequenteffectsonboneturnoverandcalciumlevels. Inelderly

people,bonelosscontinuesataslowerrateandaffectsboththetrabecularandcortical

bone(30)(Fig.2). It isworthtorememberthatthecancellousbone is thefirstoneto

respond to anymetabolic alteration, owing to its higher surface-to-volume ratio and

denservascularization(31).

21

Fig.2Bonemassresorptionrateinwomen(left)andmen(right)

Oestrogen deficiency has a multiple effect on bone metabolism. Oestrogens act by

bindingtohighaffinityreceptors(ERαandERβ)andareabletodirectlymodulatethe

activityofosteoblastsandosteoclasts(32,33),buttheycanalsoindirectlyinfluencebone

physiology,owingtothepresenceofoestrogenreceptorsonothercells(suchasstromal

cellsandcellsoftheimmunesystem)(30).However,theriseinboneformingcellsdoes

notcompensatetheriseinboneresorptioncellsandthisimbalanceresultsinboneloss

(34).

Another important function of oestrogen is to modulate the production of pro-

inflammatorycytokines,suchasinterleukin1and6(IL-1,IL-6)andtumornecrosisfactor

(TNF)-alpha (35, 36). Oestrogen withdrawal is therefore associated with a pro-

inflammatory status that stimulates bone resorption (37). There is some evidence,

however,thatthismechanismofincreasedbonelosscouldbelimitedonlytothefirst

earlystageaftermenopause(38).Ithasbeenarguedthatoestrogenwithdrawalcanalso

increase the sensitivity of bone to parathyroid hormone (PTH), intensifying the bone

resorptioneffect(39). Thisphenomenonofsecondaryhyperparathyroidismiscommon

tobothelderlymenandwomenandseemsoneofthekeymechanismsofthesecondary

slowphaseofboneloss(17).

Another key element in the establishment of secondary hyperparathyroidism in aged

peopleisvitaminDdeficiency,sinceVitaminDplaysanpivotalroleinmaintainingthe

22

appropriate calcium and phosphorus serum levels by stimulating intestinal calcium

absorption (calcemic action), thus indirectly regulating bone mineralization. The

biologically active form of Vitamin D, 1,25(OH)2D3, was demonstrated to be a key

modulatorofosteoblastandosteoclastactivity(40,41).

Moreover,numerousstudieshaveshownthatageing isassociatedwithasignificantly

reduceddifferentiation, activationand functionof osteogenic cells (42).Mesenchymal

stem cells of bone marrow tend to differentiate more into adipocytes rather than

osteoblastlineage,andthisimpairedosteoblastdevelopment/activationcontributesto

bonelossespeciallyintheelderly(43,44).

1.1.6 RISKFACTORS

Severalmodifiableandnon-modifiableriskfactorshavebeenrelatedtoosteoporosisand

arearelevantpartofthepathophysiologicalmechanismsofthesediseases.Amongthe

modifiableones themost importantandmoredefinedare: lowbodymass indexand

anorexia(BMI),alcoholconsumption,poornutrition(notonlyinsufficientdietarycalcium

intake), smoking, vitamin D deficiency, and a sedentary lifestyle. Among the non-

modifiablethemostrelevantare:riskfactors,femalegender,age,Caucasianethnicity,

earlymenopauseanddiseasesaffectingbonemetabolismarethemostlargelystudied

(45,46).

23

1.2 PERIODONTALDISEASE

1.2.1 DEFINITION

1.2.1.1 ANATOMYOFTHEPERIODONTALTISSUES

Theperiodontium(peri=around,odontos=tooth) includesthe followingtissues: the

gingiva, the periodontal ligament, the root cementum and the alveolar bone that is

continuouswiththealveolarprocess.

Theprimaryfunctionoftheperiodontiumistocreatetheattachmentbetweenthetooth

andthesurroundingbonetissueandforthisreasonisconsidered“thesupportingtissue

oftheteeth”.Thisapparatuscreatesadevelopmental,biologicandfunctionalunitthat

canchangeduetoage,functionalmodificationsandoralenvironmentalterations.Fig.3

Fig.3Theperiodontium:gingiva(G),peridontalligament(PL),root

cementum(RC),alveolarboneproper(APB),alveolarprocess(AP)

24

1.2.1.1.1 Gingiva–macroscopicanatomy

The oral mucosa consists of the masticatory mucosa (gingiva and hard palate), the

specializedmucosa(dorsumofthetongue)andtheliningmucosa(theremainingparts).

Thegingivacoversthealveolarprocessoftheboneandthecervicalportionoftheteeth.

It can be subdivided in two different layers: the epithelial layer and the underlining

connectivetissue(laminapropria).Coronallythegingivaterminateswiththefreegingival

margin, and in apical direction is continuous with the alveolar mucosa. The clearly

recognizablelinesthatseparatesthetwotypesofmucosaiscalledmucogingivaljunction.

Duringanoralexaminationtwotypesofgingivacanbedifferentiated:thefreeandthe

attachedgingiva.

Thefreegingivaisboundedbythegingivalmargincoronallyandthefreegingivalgroove

(correspondingtothecemento-enameljunction,CEJ)apically.Asmallinvaginationcalled

sulcusisformedbythefreegingivaallaroundthetoothand,whentheperiodontalprobe

isinsertedinthissulcustowardstheCEJ,alittlepocketiscreatedseparatingthetissue

fromthetoothsurface.Thissocketiscalled“periodontalpocket”or“gingivalpocket”.

Aftercomplete/physiologicaltootheruptionandinconditionofperiodontalhealththis

pocket is very thin and the soft tissues are in strictly contact to the enamel. In the

interdental area, the shape of the gingiva is determined by the contact areas of the

adjacentteeth,theCEJ,thetoothshape.Thisportionofgingivaiscalled“interdental

papilla”andcanbepyramidal, i.e. intheanteriorareawheretherearecontactpoints

betweenteeth,ormoreflattenedintheposteriorregionwherecontactareasaremore

frequent.

Theattachedgingivaisboundedbythefreegingivalgrovecoronallyandextendtothe

muco-gingivaljunctionapically.AftertheMGJtheattachedgingivabecomescontinuous

withtheliningmucosathatcoversalltheoralcavity.Themainfeaturethatcharacterized

theattachedgingivaisthefirmbondingwiththeunderliningalveolarbonebyconnective

tissue.Forthisreason,thistypeofgingivaltissueisconsiderednotmovable,contrariwise,

thealveolarmucosaisloosyboundedtothealveolarbone.Fig.4

25

Fig.4Threepartsofthegigngiva:freegingiva(FG)thatfinishesatthecemento-enameljunction(CEJ),interdental

gingiva,attachedgingiva(AG).Thedemarcationlineisthemuco-gingivaljunction(MCJ)

1.2.1.1.2 Gingiva–microscopicanatomy

Thegingivacomprisestwotypesofstructures,theepithelialtissueandtheconnective

tissue.Theepitheliumcoversallthegingivaandcanbedifferentiatedindifferentlayers:

oralepithelium(facestheoralcavity),oralsulcularepithelium(facesthetoothwithout

contact)andthejunctionalepithelium(createsthecontactgingiva-tooth).Thecontact

betweenoralepitheliumandtheunderliningconnectivetissuehasashapeofdigits.The

areasofconnectivetissuethatinvadetheepiteliumarecalledconnectivetissuepapillae,

interspersedwithepithelialridgescalledretepegs.

OralEpitheliumiskeratinized,stratified,squamousepitheliumthatcanbesubdividedin

basal layer (str. Basale), prickle cell layer (str. Spinosum), granular cell layer (str.

Granulosum)andkeratinizedcelllayer(str.Corneum).Oralepitheliumismainlymadeby

keratine-producing cells (90%) and the remaining part is made by clear cells

(malanocytes,langheranscells,merkel’scells,inflammatorycells).

Themaintissuecomponentofthegingivaistheconnectivetissue(laminapropria),made

by connective tissue fibers, fibroblasts, vessels and nerves. All these structures are

26

embeddedinanamorphousmatrixthatworksasanenvironmentforthecells.Different

typesofcellsarepresentinthe

connectivetissue:fibroblaststhatrepresentthe65%oftheentirepopulationandare

involvedinthecreationofthecollagentissueandthematrix;mastcellsthatareinvolved

intheproductionofseveralcomponentsofthematrixandinthecontroloftheblood

circulationthroughthetissues;macrophageshavealotofsynteticfunctionsandtheyare

particularly numerous in the inflamed tissue. Neutrophilic granulocytes

(polimorphonuclear leukocytes), lymphocytes and plasma cells are also present in

connectivetissue.

Connective tissue fibers, created by the fibroblasts, can be distinguished in 4 main

categoiries: collagen fibers (the most essential components of the periodontium),

reticulinfibers(presentattheinterfacesepithelium-connectivetissueandendothelium

- connective tissue), oxytalan fibers (scarse in gingiva but present in periodontal

ligament), and elastic fibers (present in associacionwith blood vessels in gingiva and

without blood vessels in liningmucosa). Although, other collagen fibers are present,

randomlyorregularlydistributed,andaccordingtotheirdirectionandtheirinsertionare

distinguished in:circular fibersCF(present inthefreegingivawithacircularshapeall

aroundthetooth),Dento-gingivalfibersDGF(embeddedinthecementumofthesupra-

alveolarportionoftherootandconnectedtothefreegingiva),dento-periostealfibers

DPF(embeddedinthecementumbutinconnectionwiththeattachedgingiva.Inthearea

betweenDGFandDPFcanbepresentalineofdepressioncalledgingivalgroove),Trans-

septalfibersTF(connectingsupraalveolarcementumofadjacentteeth).

Theconnectivetissuematrixismainlyproducedbythefibroblasts,andisamediumin

whichthefibroblastsandothercellsareembedded.Withinthematrixthereoccuranon-

stopexchangeofnutrients,metabolites,water,electrolytesandothersubstances.The

maincomponentsofthematrixareproteoglycansandglycoproteins.

27

1.2.1.1.3 Periodontalligament

Theperiodontalligament(PDL)islocatedintheslightspacebetweenrootandalveolar

boneanditisthestructureresponsibleoftheconnectionbetweenthelaminaduraand

thetoothcementum.Theligamentisarichlyvascular,softtissuethatcompletelyencircle

therootandisincontinuouswiththelaminapropriaofthegingivacoronally.Thewidth

ofperiodontalligamentisabout0,25mm(0.2-0.4mmrange)andhismainfunctionisto

adsorbanddistribute themasticatory loadaswellas theocclusal forcesduringother

toothcontacts.AccordingtothePDLcharacteristics(width,height,quality)themobility

patternofteethcanbedifferent.

DifferentbundlesofcollagenfibersconstitutetheperiodontalligamentandItispossible

todistinguish4differenttypesdependingontheirorientation:alveolarfiberscrestAFC,

horizontalfibresHF,obliquefibresOF,apicalfibersAF(Fig.6).TheprincipalcollagenI

fibers of the PDL are located between the cementum and the alveolar bone, and

penetrateboththecementumandthebonesurface.ThistypeoffiberiscalledSharpey’s

Fig.5Theschematicdrawingofthehistologicsectiondescribingthecompositionofthegingivaand

thecontactareabetweenthegingivaandtheenamel.

28

fiber.Inaddition,thePDLcontainsoxytalanefibersthatrunaroundbloodvesselswithan

apico-occlusalorientationandtheyarealsoinsertedinthecementum.

The ligament is colonized by several cells as fibroblasts (along principal fibers),

osteoblasts (on the bone surface), cementoblasts (on the cementum surface),

osteoclasts, epithelial cells as well as nerve fibers. Epithelial cells are called Rest of

Mallassezandareorganizedinclustersonrootsurface.Thesecellsarearemnantofthe

Hertwig’sepithelialrootsheath.Thesecellsarestillvitalbutwithapoormetabolism.

1.2.1.1.4 Rootcementum

The cementum is a tissue covering the tooth root characterized by several bone-like

features. It is a mineralized highly specialized structure without blood vessels and

innervation. Cementum undergoes a continue reposition during life increasing in

thicknessbytheadditionofnewlayersbut,asopposedtothebone,doesnotpresent

alternated periods of resorption and apposition. It is formed by collagen fibred

embeddedinanorganicmatrixlikeothermineralizedtissuesandcontainsmoreorless

Fig.6Schematicdrawofperiodontalligamentwithfibersorientation:

alveolarboneproper(ABP),rootcementum(RC),alveolarcrestfibers(ACF),

horizontalfibers(HF),obliquefibers(OF)andapicalfibers(APF)

29

asmuchhydroxyapatiteasthebone(65%vs60%) in itsmineralizedcomposition.The

two functionsof the cementumare: linking theperiodontal ligament to the rootand

contributetotherepairingprocessesoftherootincaseofdamage.Rootcementumcan

bedivided in threedifferent types: Acellular extrinsic fiber cementumAEFC (situated

coronallyandinthemiddleportionoftherootandcontainstheSharpay’sfibers),Cellular

mixed stratified cementum CMSC (in the apical third and in the furcations), Cellular

intrinsicfibercementumCIFC(foundinresorptionlacunae).Sharpey’sfibersconstitute

theextrinsicfibersystemofthecementumandareprovidebyfibroblasts,contrarywise,

theintrinsicfibersystemismadebybundlesorientatedmainlyparalleltothelongaxisof

thetoothandisproducedbycementoblasts.Sharpey’sfibersareconstitutedbyanon-

mineralized central part and two mineralized termination that are embedded into

cementumandbone.

Cementum,throughoutthelife,becomeswiderintheapicalportionthatcanreachthe

widthof150-250microns,incomparisontothecoronalareawherethethicknessisabout

20-50microns.

1.2.1.1.5 Alveolarbone

Thealveolarprocess is theportionof jawbonesthat includeandsupport theteeth. It

developsatthesametimeofthedevelopmentanderuptionoftheteeth.Thealveolar

bone composes the attachment structure of tooth in combination with periodontal

ligamentandrootcementum.Themainfunctionoftheapparatusistoadsorb,distribute

andmodulatethemasticatoryandocclusalload.Thewallsofthesocketthatcontainsthe

teetharecoveredbycorticalbone,whiletheareasbetweenwallsandbetweensockets

ofadjacentteethareconstitutedbycancellousbone,fulloftrabeculae(Fig.7).Inmaxilla,

bonewallsof the socketsare thinnerat thebuccal aspect if compared to thepalatal

aspectandthethicknesscanvaryindifferentareasofthemouth.Inposteriorareaofthe

mandiblethebonewallinthebuccalaspectisthickerthantheboneinlingualarea,this

isemphasizedbythepresenceofthelineaobliquaatlevelofsecondandthirdmolars.In

general,socketswallsbecomethinnerfrommolarregiontoanteriorarea.Thelayerof

30

boneinthesocketinwhichSharpey’sfibresareinsertediscalledbundlebone,atypeof

bonewithsomecementum-likefeaturesandahighturnoverrate.Thealveolarboneis

constantly renewed as response to functional stimuli with a non-stop resorption-

repositionpattern.Thesephysiologicalfunctionaldemandsincludemasticatoryloading,

occlusalforcesorteethmovements.Thecellsinvolvedinthisprocessofresorptionare

osteoclasts,agiantcelltypespecializedinmineralizationmatrixbrakeagebytherelease

ofacids.Thecontinuousremodelingpatternaffectscorticalaswellascancellousbone,

after bone resorption acted by osteoclast, the newly formed bone is deposed by

osteoblastsandanewBoneMulticellularUnitBMU(the“structure”composedbyallthe

cellsandvascularsupplynecessaryforboneremodeling)iscreated.

1.2.1.1.6 Bloodsupplyoftheperiodontium

Hardandsofttissuesofthemaxillaandthemandiblearesuppliedbyacomplexsystem

ofbloodvesselsratherthansinglegroupsofvessels.Infact,oralcavityischaracterized

by a packednetwork of anastomoses. Periodontal tissue and teeth is vascularizedby

vesselsfromtheinternalmaxillaryartery(IMA),thatdismissestheinternalalveolarartery

(IAA) in themaxilla and in themandible. In correspondenceofeach tooth thedental

artery(DA)originatesfromtheIAAandcarriesontowardsthedentalapexand,before

Fig.7Verticalsectionsthroughvariousregionsofmandibulardentition.Thebonewallatthebuccal(B)

andlingual(L)aspect

31

entering thedental socket,dismisses the intraseptalartery (AI)with ramiperforantes

(RRP)thatcompenetratestheperiodontalligament.Beneaththejunctionalepithelium

thereisafinemeshnetworkofsmallvesselswithoutloopscalleddento-ginigivalplexus

(DGP).

Gingiva,contrarywise,receivesthebloodsupplymainlythroughsupraperiostealvessels

asterminalbranchesofagroupofarteries:thesublingualartery,thementalartery,the

buccalartery,thefacialartery,thegreaterpalatineartery,theinfraorbitarialarteryand

theposteriorsuperiordentalartery.Thisnetworkcreatesthesubepithelialplexus(SP)in

correspondence of free and attached gingiva. The plexus is characterized by several

capillary loops projected from connective rete pegs to the epithelium. Free gingiva

vascularization in completed and integrated by terminal branches coming from the

periodontalligamentinanastomoseswithsupraperiostealandbonevessels.Fig.8

1.2.1.1.7 Lymphaticsystemoftheperiodontium

The lymphatic structures in periodontium are not easily identified because of the

dimension. Infact,the lymphcapillariesthatformanextensivenetwork inconnective

Fig.8Theschematicdrawofthebloodsupplytotheteethandtheperiodontaltissues:theintraseptal

artery(B),periodontalligamentartery(A)andsupraperiostealvessels(C)

32

tissuearecharacterizedbyawallformbyasinglelayerofendothelialcells.Beforethe

entranceinthebloodstream,thelymphpassesthroughagroupoflymphnodesinwhich

isfilteredandsuppliedwithlymphocytes.Allperiodontallymphaticdrainageiscollected

inheadandnecknodes.Forthemandible,thedrainagefromtheanteriorgingivaandlips

is collected in the submental nodes and for buccal/lingual gingiva of premolar/molar

areastothesubmandibularnodes.Regardingthemaxilla,thepalatalgingivaisdrained

tothedeepcervicalnodesandthebuccalgingivaisdrainedtothesubmandibularnodes.

Exceptforthethirdmolars,thatdraintothejagulogastricnode,andforthemandibular

incisors,thatdrainstothesubmentalnodes,alltheteethandtherelativeperiodontium

aredrainedtothesubmandibularlymphnodes.Fig.10

Fig.9Schematicdrawofthelymphaticsystem:Jagulodigastricnode(JD),deepcervicalnodes

(CP),sub-mandibularnodes(SMA)andsubmentalnodes(SME)

33

1.2.1.1.8 Nervesoftheperiodontium

Periodontium contains nociceptors and mechanoreceptors that can transfer the

informationaboutpain,touchandpressure.Thesenerveshavethetrophiccenterinthe

semilunarganglionandcomestotheperiodontiumwithtrigeminalnerveanditsthree

branches.Thepresenceofaverythinmetalfoilcanbeidentifiedbytheperiodontium

(10-30microns).Periodontalreceptorstogetherwiththeproprioceptorsinmusclesand

tendons can be considered themasticatory system of the jaws playing a key role in

regulationofchewingandocclusionmovements.

Theteethof theupper jaware innervatedby thesuperioralveolarplexus,and in the

lowerjawbytheinferioralveolarnerve.Fortheperiodontiumthenervoussystemisthe

same of the dental systembut the small nerves that go from themain nerve to the

periodontalspacefollowthesamecourseofthecorrespondingbloodvessel.

Inthemaxilla,thegingivaofbuccalaspectofincisors/canines/premolarsisinnervatedby

superior labial branches from the infraorbital branch,while themolar gingiva on the

buccalaspect issuppliedbytheposteriorsuperiordentalnerve.Thepalatalgingiva is

innervatedbythegreaterpalatalnerveexceptfortheincisorsarea,servedbythelong

sphenopalatinenerve.Regardingthemandible,thelingualgingivaisinnervatedbythe

sublingualnerve(terminalbranchofthelingualnerve).Inthelabialaspectoftheincisors

andcanines thegingiva is suppliedby thementalnerve,while themolarareaby the

buccalnervebut,inthepremolarregionthetwonervesfrequentlyoverlap.Fig.10

34

1.2.1.2 FEATURESOFPERIODONTALDISEASE

Periodontal diseases are a class of infections characterized by the presence of

microorganismsthatcolonizethetoothsurfaceatorbelowthegingivalmargin.While

billionsofmicroorganismscolonizecontinuallythetooth,mostsitesinmostpatientsdo

notshowlossofsupportingtissuesatanytime.Therelationshipbetweenperiodontal

microbiota and the host is in balance normally, but sometimes, a specific group of

bacteria takes over the balance and lead to periodontal damage. Like other human

infection,periodontaldiseaseischaracterizedbythepresenceofperiodontalpathogens,

butisofprimaryimportancetoconsiderthatthisconditionisnecessarybutnotsufficient

toatissuedestruction.Inalargenumberofindividualsinwhichtheteetharecolonized

byperiodontalpathogensatbothlevels(supraorsubgingiva),thesignsofperiodontal

sufferingareabsentandthisisnotananomaly.Inthesamewayofalltheotherinfection

inthehumanbody,wheredifferentbacterialspecieshavedifferenttissuesspecificities

and targets, periodontal disease appear to be caused by a restricted number of

pathogens acting alone or in combination. These species include: Aggregatibacter

actinomycetemcomitans, Tannerella forsythia, Campylobacter rectus, Eubacterium

Fig.10Schematicdrawoftheinnervationofthejaws

35

nodatum, Fusobacterium nucleatum, Peptostreptococcus micros, Porphyromonas

gingivalis,Prevotella intermedia,Prevotellanigrescens,Streptococcus intermediusand

Treponema(47).

The peculiar feature of periodontal infection is the presence of a “unusual anatomic

featurethatamineralizedstructure,thetooth,passesthroughtheintegument,sothat

partofitisexposedtotheexternalenvironmentwhilepartofiswithintheconnective

tissue”.Themicroorganismsthatcausethediseaseresideinabiofilmthatexistontooth

or on the epithelial surface. Themajor characteristic of the diseases is that they are

causedbybacteriathatresideinabiofilmoutsidethebodyandtheirtreatment,aswell

asthediagnosisandtheprognosis,iscomplex.

Ingeneral,periodontaldiseasesareaclassofparaphysiologicconditionsorpathologies

characterizedbybacterial colonization, soft tissue inflammationand/or soft andhard

tissuedestruction.

1.2.1.3 EXAMINATIONMETHODS

Examinationofperiodontalconditionsconsistsofclinicalassessmentofinflammationin

periodontaltissues,recordingofprobingdepthandclinicalattachmentlevels,besidesa

radiographicassessmentofalveolarbone.Fig.11

Fig.11Probingdepthinacompromised(left)andhealty(right)

peridontalpocket

36

1.2.1.3.1 Inflammationassessment

Presenceofinflammationatgingivalmargininevaluatedinsertingametalprobetothe

bottomofagingivalpocketaccordingtotheprinciplesoftheGingivalIndexpublishedby

Loein1967wherethecompleteabsenceofinflammationatthemarginwasrecordedas

0, the light tendency to inflammation with a change in color and appearance was

recordedas1,aslightbleedingafterprobingwasrecordedas2andthespontaneous

bleedingwas3(48).Asimilarscorewassettorecordthepresenceofplaquewhere0

was recorded in absence of deposits, 1 in presence of plaque visible moving the

periodontalprobealongthemargin,2whentheplaquewasclearlyvisibleand3ifthe

plaquewasabundant(49).

Later,simplifiedvariantsofthesetypesofscoringhavebeenproposedandused(50).

These “new” scores are based on the dichotomy between presence or absence of

bleedingandplaque.Inthisway,0recordstheabsenceand1recordsthepresenceof

bleeding/plaque (“dichotomous scores”). Thebleedinghas to startwithin 15 seconds

after theprobingandthis iscalledbleedingonprobing (BOP). Incaseofa fullmouth

assessment six sites per tooth are probed and a Bleeding on Probing index can be

recorded.ThemeanBoPscoreisgivenasapercentage,andthisindexcanbeusedasa

negativepredictorofperiodontaldisease(51).Likewise,ifthePlaqueisassessedinafull

mouthexamination,aPlaque Indexcanbeeasilyrecorded.Thesetwo indexescanbe

easily used in order to analyse and compare the periodontal inflammation status at

differentobservationperiods.Fig.12

37

1.2.1.3.2 Periodontalsupportassessment

Avarietyofexaminationindexhasbeenproposedovertheyears.Inordertoevaluate

theamountoftissuelostandtoidentifytheapicalextensionoftheinflammatorylesion,

thefollowingparametersshouldberecorded:

- Probingpocketdepth(PPD)

- Clinicalattachmentlevel(CAL)

- Furcationinvolvement(FI)

- Toothmobility(TM)

Nowadays,lossofperiodontalsupportisassessedbyrecordingofperiodontalprobing

depth(PPD),definedasthedistancebetweenthegingivalmargintothelocationofthe

tipofaperiodontalprobe,withastandardizedtipdiameterof0,4/0,5mm,insertedin

thepocketwithmoderateforce.InaperiodontalchartPPD<4mmaremarkedinblack

whiledeepersoundingwithPPD>4mmarered.Redfiguresrepresentthediseasedsites

bothfromaseverityandextensionpointofview.Severalstudieshavedemonstratedthat

PPD is themost valuable tool in clinical attachment loss prediction. In particular PPD

associatedtoBOP+hasthehigherlevelofpredictabilityat42months(52),moreover,

Fig.12Differentdegreesofinflammationinaperiodontaltissue

38

residual pockets of 7mm have a predictability of 50% at 5 years and an increase of

PPD>1mmhasapredictabilityof80%at5years(53).

Instead, clinical attachment level (CAL) is defined as the distance from the cemento-

enameljunction(CEJ)andthetipoftheprobe.Inafullmouthexamination,anumberof

six points per tooth of the entire dentition aremeasured by probing (buccal, lingual,

interproximal).Incaseofrecession,thedistancebetweenfreegingivalmarginandthe

CEJ turns negative and the height of the recession has to be added to the PPD to

determinetheCAL.

Intheprogressionofperiodontaldiseaseonmulti-rootedteeth,thedestructiveprocess

caninvolvethestructuresaroundthefurcationarea.Furcationinvolvementisassessed

fromalltheentrancesofpossibleperiodontallesionsofmulti-rootedteethwithacurved

periodontalprobegraduatedat3mmcalled“NabersFurcationProbe”,anddepending

onthepenetratingdepth,FIareclassifiedas(54):

- F1:horizontalPD<3mmfromoneortwoentrances

- F2:horizontalPD>3mminatthemostonefurcationentranceorincombination

withadegreeF1

- F3: horizontal PD > 3 mm in two or more furcation entrances (through-and-

through)

Afterwards,in1984theclassificationhasbeenintegratedtakingintoaccountthevertical

distructionofperiodontalsupportandthreeclassescanbedefinedbesidesthehorizontal

penetrationdeegres(55)(Fig.13):

- ClassA:1-3mmofPD

- ClassB:4-6mmofPD

- ClassC:>7mmofPD

39

Thecontinuouslossofperiodontalsupportingtissueovertimemayresultinincreased

tooth mobility, as well as the occlusal trauma. Increased tooth mobility has been

classifiedin1950byMiller(56):

- Degree0:Physiologicalmobilityof0,2-0,1mminahorizontaldirection

- Degree1:increasedmobilityatleast1mminahorizontaldirection

- Degree2:visuallyincreasedmobilityexceeding1mminahorizontaldirection

- Degree3:severemobilityofthecrowninbothhorizontalandverticaldirection

(nofunction)

Iscrucialto identifythecauseofthemobility, inordertoplanthepropertherapeutic

approach,infactseveralfactorscouldleadtoanincreasetoothmobilitylikeoverloading,

periapicallesions,periodontalsurgery,periodontaldisease.Fig.14

Fig.13Furcationsounding:TheNabersprobeentersthefurcationaccordingtohorizontalthebonedestruction

(F1,F2,F3,left).Thegradingofverticalboneresorption:AifF<3mm,Bif3mm<F<6mm,CifF>6mm(right)

Fig.14Toothmobilityassessment

40

1.2.1.3.3 Radiographicevaluation

Radiologyiswidelyusedinperiodontologybutthelimitationsinsupportingtissueloss

evaluationarewellknown(57).Assessmentofbonelossinradiographscanbeusedto

evaluate: the presence of lamina dura, the width of periodontal ligament, the

morphologyofbonecrest,thedistancebetweenCEJandbonecrest,theshape/distance

of the roots. In general, radiological assessment is consideredauseful toolmainly to

perform epidemiological studies, rather than in clinical examination, where the

periodontalproberemainsthemostreliableappliance.Fig.15

1.2.2 DIAGNOSISOFPERIODONTALDISEASE

Basedontheinformationregardingtheconditionofthevariousperiodontalstructures

(gingiva, periodontal ligament, alveolar bone) which has been obtained through the

comprehensiveexaminationlistedabove,aclassificationaswellasadiagnosisforeach

tooth regarding the periodontal conditionsmay be given. Four different tooth-based

diagnosismaybeused:

Fig.15Completeapico-periapicalstatus

41

- Gingivitis:teeththatshowbleedingonprobingbutthesulcusdepthremainsata

physiologicallevelof1-3mmirrespectiveofthelevelofclinicalattachment.The

diagnoseofgingivitischaracterizedlesionsconfinedtothegingivalmargin.

- Periodontitis“mild-moderate”:gingivitisincombinationwithattachmentlossis

termed “periodontitis”. If the PPD do not exceed 6mm, a diagnosis of mild-

moderate periodontitis is given irrespective of themorphology of periodontal

lesion. This diagnosis can be applied to teeth with horizontal bone loss,

representing suprabony lesions and/or vertical or angular bone loss with

infrabonydefects(one/two/threewallsdefectsorcraters).

- Periodontitis “advanced”: If PPD exceeds 6 mm, a diagnosis of advanced

periodontitis isgiven irrespectiveofthemorphologyofperiodontal lesion.The

distinctionwiththemild-moderateisonlybasedonthePPD,infacthorizontalas

wellasverticaldefectscanbepresent.

- Periodontitis interradicularis: This is the periodontitis characterized by the

involvementofthefurcationarea.IfafurcationisinvolvedwithaPPD<4mmitis

consideredmildmoderate,ifPPD>4isconsideredadvancedperiodontitis.

1.2.3 CLASSIFICATIONOFPERIODONTALDISEASE

The currently use d classification of periodontal diseasewas introduced by the 1999

InternationalWorkshop foraClassificationofPeriodontalDiseaseandConditionsand

encompasseseightmaincategories,namely:

1. Gingivaldisease

2. Chronicperiodontitis

3. Aggressiveperiodontitis

4. Periodontitisamanifestationofsystemicdisease

5. Necrotizingperiodontaldisease

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6. Abscessesoftheperiodontium

7. Periodontitisassociatedwithendodonticlesions

8. Developmentaloracquireddeformitiesandconditions

1.2.3.1 GINGIVALDISEASE

It is demonstrated that inflammation of the gingiva induced by bacteria is themost

commonformofgingivitis(58),andthecategorizationofdiseasesaffectingthegingiva

requiresevaluationofpatientsignsandsymptoms,medicalanddentalhistories,aclinical

examinationthatincludestheextend,distribution,durationandthephysicaldescription

oflesions.Theuniversalfeaturesofgingivaldiseaseincludeclinicalsignsofinflammation,

signs and symptoms that are confined to the gingiva, reversibility of the disease by

removalofetiology,thepresenceofbacteria-ladenplaquetoinitiateand/orexacerbate

theseverityofthelesion,andapossibleroleasaprecursortoattachmentlossaround

teeth. The intensity of the clinical signs and symptomsof gingivitiswill vary between

individuals(59),aswellasbetweensiteswithinadentition.Thecommonclinicalfindings

ofplaque-inducedgingivitisincludeerythema,edema,bleeding,sensitivity,tenderness

andenlargement(58).Veryspecificfeaturesofgingivitisaretheabsenceofsupporting

structure lossand the reversibility.According toLöe, it is important tounderline that

gingivitisbecomesmanifestonlyafterdaysorweeksofplaqueaccumulation.

Gingival inflammation, clinically presenting as gingivitis, is not always due to

accumulationofplaqueonthetoothsurface,thisspecificcategoryofgingivitisiscalled

“non-plaqueinducedinflammatorygingivallesions”(60).Theymayoccurduetoseveral

causes,suchasspecificbacterial,viralorfungalinfectionwithoutanassociatedplaque-

related gingival inflammatory reaction. Gingival lesions of genetic origin are seen in

hereditary gingival fibromatosis, and severalmucocutaneousdisorders (lichenplanus,

pemphigus,pemphigoidsanderythemamultiforme).Allergicandtraumaticlesionsare

otherexamplesofgingivaldiseasenon-plaquerelated.

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1.2.3.2 CHRONICPERIODONTITIS

Chronicperiodontitisisconsideredtostartasplaque-inducedgingivitis,areversible

conditionleftuntreated.TheclinicalfeaturesofCPincludesymptomssuchas

color/texture/volumealterationsofthemarginalgingiva,bleedingonprobingfrom

gingivalpockets,increasingprobingdepth,lossofclinicalattachment,recessionofthe

gingivalmargin,lossofalveolarbone,rootfurcationexposure,increasedtoothmobility,

driftingand,eventually,exfoliationofteeth.

Chronicperiodontitishassomepeculiaritiesthatcanhelptheclinicianindiagnose:

- CPisprevalentinadultsbutmayoccuralsoinchildren

- Thedestructionoftheperiodontaltissuesseeiscommiseratedwithoral

hygienelevel,localpredisposingfactors,smoking,stressandsystemicrisk

factors.

- Subgingivalbiofilmharborsavarietyofbacterialspecies(biofilmcomposition

variesbetweenindividualsandsites)

- CPisclassifiedaslocalizedwhenlessthan30%ofsitesareaffected,contrariwise

isdefinedgeneralized

- Severityofchronicperiodontitisatthesitelevelcanbeclassifiedbasedonthe

degreeofclinicalattachmentlossasmild(1-2mm),moderate(3-4mm),severe

(>5mm)

- AlthoughCPisinitiatedbyplaque,hostfactorsdeterminethepathogenesisand

progressionrateofthedisease

- Therateofprogressioninmainlyslowormoderate(butafasterprogressioncan

occur)

Ifgingivitisbecomesmanifestonlyafterweeksofplaqueaccumulation,chronic

periodontitisrequiresfarlongerperiodsofplaqueandcalculusexposuretodevelop

(61,62).TissuedestructioninCPdoesnotaffectallteethevenly,buthasasite

predilection.Asresultsinthesamedentition,someteethmaybeseverelyaffected

whileotherteethcanbealmostfreefromtheperiodontaldestruction.Regardingthe

44

progressionofthedisease,acontinuousslowprocesswithperiodsofexacerbation

(burst)seemsthemostconcertedpattern.Ingeneral,itisimportanttoknowthat

factorsassociatedtothediseasecaninfluencethediseaseprogression.Furthermore,

theextensionandtheseverityofthediseasearegoodpredictorsoffuturedisease

occurrence.

1.2.3.3 AGGRESSIVEPERIODONTITIS

Aggressiveperiodontitis(AgP)comprisesagroupofrare,oftensevere,rapidly

progressiveformsofperiodontitisoftencharacterizedbyanearlyageofclinical

manifestation.Intheabsenceofanetiologicalclassification,aggressiveformsof

periodontaldiseasehavebeendefinedbasedonthefollowingprimary,universally

present,features:

- non-contributorymedicalhistory

- rapidattachmentlossandbonedestruction

- familialaggregationofcases

Andsecondary,generallybutnotuniversallypresent,features:

- Amountsofmicrobialdepositsinconsistentwiththeperiodontaldestruction

- ElevatedpresenceofAggregatibacterActinomicetemcomitansand

PorphiromonasGingivalis

- Phagocyteabnormalities

- Hyperresponsivemacrophagephenotype,includingelevatedproductionof

ProstaglandinE2andinterleukin-1B

- Progressionofattachmentlossandbonelossmaybeself-arresting

- Iflocalizedaggressiveperiodontitis:

o Circumpubertalonset

o Localizedfirstmolar/incisorwithinterproximallossofattachmentonat

least2permanentteeth,oneofwhichisafirstmolar,andinvolvingnon

morethantwoteethotherfirstmolarandincisors

45

o Robustserumantibodyresponsetoinfectingagent

- Ifgeneralizedaggressiveperiodontitis:

o Usuallyaffectingpersonsunder30yearsofagebutsometimescanbe

older

o Generalizedinterproximallossaffectingatleast3teethotherthanfirst

molarsandincisors

o Pronouncedepisodicnatureofthedestructionofattachmentanalveolar

bone

o Poorserumantibodyresponsetoinfectingagent

Diagnosisofoneoftheseformsrequirestheabsenceofsystemicdiseasesthatmay

impairhostdefensesandleadtoprematureexfoliationofteeth.Theearly

manifestationofclinicallydetectablelesionsisgenerallyinterpretedasbeingthe

expressionofhighlyvirulentcausativeagentsorhighlevelsofsusceptibilityofthe

individualpatient,oracombinationoftwo(63).

1.2.3.4 PERIODONTALDISEASEASARISKFORSYSTEMICDISEASE

Theevidenceabouttheimplicationofperiodontaldiseaseasariskfactorforseveral

systemicconditionssuchascardiovasculardisease,adversepregnancyoutcome,

diabetes,andpulmonarydisease,hasemergedsince1990s(64).Thefindingsgathered

fromtheinvestigatorsworldwideinthelast60yearsareverycompelling,anditwould

certainlyappearthatperiodontaldiseaseisstronglyassociatedwithsystemic

conditions.Forthisreason,dentistrymustfocusoninterventionstudiestodetermine

whethertreatingperiodontitiswillhaveabeneficialeffectonsystemicdisease.

Regardingcardiovasculardisease,evidencedemonstratingthebeneficialeffectsof

periotreatmentsonthediseaseoutcomeislimitedandindirect(65).Inconsidering

adversepregnancyoutcomes,fewstudiesprovideevidencethatpreventivetreatments

aimedtoreducedmaternalperiodontalinfectionmayreducethelikelihoodofpreterm

lowbirthweightinfants(66).

46

Numerousepidemiologicsurveysdemonstrateanincreasedprevalenceofperiodontitis

amongpatientswithuncontrolledorpoorlycontrolleddiabetesmellitus.Moreover,

diagnosingDiabetestype2,investigatorsfoundahigherprevalenceofclinicaland

radiologicalattachmentlossfordiabeticsversusnon-diabeticpatients.Hence,itisclear

thatdiabetesisamodifierorriskfactorforperiodontaldisease(67).Itisalso

demonstratedthatperiodontalinfectionreductioncanimproveglycemiccontrol(68,

69).

Thereareanumberofstudieswhichexaminetheeffectoftreatingoralinfectionin

reducingtheriskofpneumoniainhigh-riskpopulations(69).Recentreviewsclearly

indicatethatwhenbacterialplaqueisreducedinmouthofat-riskpatients,theriskof

pneumoniaisreduced.

1.2.3.5 NECROTIZINGPERIODONTALDISEASE

Necrotizinggingivitis(NG)andnecrotizingperiodontitis(NP)arethemostsevere

inflammatorydisorderscausedbyplaquebacteria.Theselesions,usually,runanacute

courseandarerapidlydestructiveanddebilitating(70).Necrotizingdiseaseisan

inflammatorydestructiveperiodontalconditioncharacterizedbyulceratedandnecrotic

papillaeandgingivalmarginresultinginapunched-outappearance.Theulcersare

coveredbyayellowishwithorgrayishslough,termed“pseudomembrane”.Removalof

thematerialresultsinaulcerativelesionwithmassivebleeding.Thelesionsappear

rapidlyandarepainfull,evenifintheearlystagepaincouldbemoderate.Thelesions

areseldomassociatedwithdeeppocketsbecausegingivalnecrosisiscommonly

associatedtoacrater-likeinterproximalbonedestruction.

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1.2.3.6 ABSCESSESOFTHEPERIODONTIUM

Odontogenicabscessesincludeabroadgroupofacuteinfectionsthatoriginatefrom

thetoothand/ortheperiodontium.Suchabscessesareassociatedwithanarrayof

symptomsincludinglocalizedpurulentinflammationintheperiodontaltissuesthat

causespainandswelling.Dependingontheoriginoftheinfectionlesionscanbe

classifiedasperiapical,periodontalandpericoronayabscesses.Aclassificationhasbeen

proposedandincludedgingivalabscesses,causedbyimpactationofforeignbodies,

periodontalabscesses,eitheracuteorchronicdependingonaperiodontalpocket,and

pericoronalabscesses,fortheincompleteeruptionofatooth.Periodontalabscesses

classificationisbasedontheetiology:

- periodontitis-relatedabscess:ifanacuteinfectionoccursfrombacteriapresent

inadeepperiodontalpocket

- non-periodontitis-relatedabscess:whentheinfectionoriginatesfromadifferent

source,suchasforeignbodyimpactionoranalteredrootintegrity.

1.2.3.7 PERIODONTITISASSOCIATEDWITHENDODONTICLESIONS

Lesionofendodonticoriginaresignificantastheyfrequentlyextendandmanifest

themselvesintheattachmentapparatus.Notonlydotheselesionsproducesignsand

symptomsofinflammationinapicalareabutalsoalongthelateralaspectofrootsand

infurcationareas.Thefactthattheperiodontiumandthedentalpulpareanatomically

interconnectedalsoimpliesthatexchangeofnoxiousagentsmayoccurinboth

directions(71).Ingeneral,periodontal-endodonticlesionsareusuallyatooth-related

andnotpatient-relateddiseaseand,forthisreasoncanoccureitherinperiodontalor

non-periodontalpatients.Hence,thistypeofperiodontallesionisnotconsidereda

diseasethatcanaffectthepatientbutonlythesite.

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1.2.4 EPIDEMIOLOGYOFPERIODONTALDISEASE

Epidemiologyisdefinedas“thestudyofthedistributionofadiseaseoraphysiological

conditioninhumanpopulationandthefactorsthataffectthisdistribution”(72).Based

on this definition and previous epidemiological research in the medical field, in

periodontal research, is it of primary importance the study of the prevalence of the

diseaseindifferentpopulations(frequency,severity,changes).

1.2.4.1 PREVALENCEOFPERIODONTALDISEASE

Since the last classification has been introduced in June 2018, a substantial part of

existing literature on the prevalence and extend of periodontal disease in various

populationsisstillbasedonanearlyclassificationofthedisease.Currently,twoprincipal

forms of destructive periodontal disease are recognized – chronic periodontitis and

aggressive periodontitis (73). It is relevant to attempt to appraise some key features

relevanttotheepidemiologyofhumanperiodontitisthatunderlieitscore‘identity’asa

bacterial biofilm-induced inflammatory disease. There is consensus that the

epidemiologic hallmark of periodontitis is destruction of the tooth-supporting tissues

manifestedbyclinicalattachmentlossandradiographicboneloss.Aspecialfeatureof

periodontitisisitssitespecificity,andanimportantconsequenceofthissitespecificityis

thatanymeasureofperiodontitisasapathologicconditionwhichaffectsanindividual

ratherthanatooth/toothsitemustincorporateameasureofextentandalsoameasure

ofseverity.Toconfusetheissuefurther,allbiologicmeasurements,includingattachment

loss andbone loss, are subject toboth temporalbiologic variationandmeasurement

errors(74).Auniversallyaccepteddefinitionoftheappropriatecombinationofextent

andseverityvaluestodenotea‘caseofperiodontitis’hasnotbeenestablishedandisone

of the reasons why prevalence estimates of periodontitis vary considerably across

studies.Indevelopedcountries,thereisgrowingconsensusthatavalidexaminationof

periodontal status should include full-mouth assessments of gingival/periodontal

inflammation,probingdepthandattachmentloss,inotherwordsmeasurementsatsix

sites per tooth at all teeth present in the dentition and continuous, rather than

49

dichotomous, measures of extent and severity. According to the World Health

Organizationpublication,‘TowardsaCommonLanguageforFunctioning,Disabilityand

Health: The International Classification of Functioning, Disability andHealth’, appears

reasonabletoassumethatformsofhighextentandseverityarethosemostlikelytobe

capableofnegativelyaffectingthefunctionandwell-beingofanindividual.Butifwetry

to understand why it has not been feasible to establish a universal definition of

periodontitis forepidemiologicuse, it is important toconsider that the sameseverity

level of periodontitis signifies vastly different prognosis at different ages: 6 mm of

attachmentlossatage80maybeperfectlycompatiblewiththeretentionofafunctional

dentitionforlife;however,thesamemagnitudeofattachmentlossaffectingateenager

suggestsasignificantlyworseprognosiswithrespecttotoothfunctionandsurvival(75).

Althoughperiodontitisisoftencalleda‘silent’diseasebecauseitisrarelyassociatedwith

obvioussignsandsymptomsunlessthediseasehasprogressedtoitsterminalstages.A

keyissueinthepresentdiscussionisthecurrentprevalenceestimatesofperiodontitis.A

systematicreviewincluding72studiesanddatafrom291,170individuals≥15yearsof

age from37countriesestimated that theglobalprevalenceof severeperiodontitis in

2010amountedto10.8%(95%confidenceinterval:10.1–11.6%),affecting743million

people worldwide and representing the sixth most prevalent condition (76). The

prevalencevariedaccordingtoworldregions,withsouthernLatinAmericaandeastSub-

Saharan regions scoring the highest prevalence, of 20%.We argue that the currently

adopted epidemiologicmethodologies/definitions that result in an almost ubiquitous

prevalenceofperiodontitisindeedoverestimatetheoccurrenceofthediseasethatmay

actuallyput individualsatatruebiologic, functionalorpsychosocialdisadvantage.For

thisreason,nowadays,amultidimensionalapproachtotheassessmentofperiodontitis

wouldfacilitateanimprovedunderstandingofitsepidemiologyanditsconsequences.

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1.2.5 ETIOPATHOGENESISOFPERIODONTALDISEASE

1.2.5.1 MICROBIALETIOLOGY

Periodontitisisacomplexdiseasewithmultiplecomponentcauses,somewiththeirbasis

ingenetics,somecausedbyepigeneticinfluencesandothersthataremodifiablebecause

they relate to patient behaviors, medications or environmental factors, all of which

conspiretoestablishandpropagatetheperiodontitislesion(77).

1.2.5.1.1 Dentalplaqueandthebiofilmconcept

Ingeneral,alltheinterfacesurfacesofthebodyareexposedtocolonizationbyawide

rangeofmicro-organismandtheestablishmicrobiotaliveinharmonywiththehost.The

accumulationandmetabolismofbacteriaonhardoraltissueisconsideredtheprimary

causeofdentaldiseasesuchas:caries,gingivitis,periodontitis,peri-implant infections

andstomatitis.Plaqueremoval,infact,leadstothedisappearanceoftheclinicalsignsof

inflammation(58).Theterm“infection”referstothepresenceandmultiplicationofa

micro-organisminbodytissue.Dentalplaquemayaccumulatesupragingivallybutalso

below the gingivalmargin,with a different composition ofmicrobiota, that has been

attributedtothelocalavailabilityofbloodproducts,pocketdepth,redoxpotentialand

O2(78).Theabilitytoadheretosurfacesisageneralpropertyofalmostallbacteria.The

term“biofilm”describesthemicrobialcommunityassociatedwithatoothsurface,Inthe

lower levels of most biofilms a dense layer of microbes is bound together in a

polysaccharidematrixwithorganicandinorganicmaterials.Biofilmprotectbacteriafrom

antimicrobicagents,and,forthisreason,treatmentswithantimicrobicagentswithouta

mechanical plaque removal are unsuccessful. Literature data indicate that our host-

associatedpolymicrobialcommunities,suchasthosefoundintheoralcavity,co-evolved

withusandhavebecomean integralpartofwhoweare. Indeed,Roberts&Darveau

arguethatweshouldconsiderthemicrobiomeasahumanorgan.(79)

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1.2.5.1.2 Plaque-formationmechanism

Immediatelyuponimmersionofasolidsubstratumintothefluidmediaoftheoralcavity,

oruponcleaningofasolidsurfaceinthemouth,hydrophobicandmacromoleculesbegin

toadsorbtothesurfacetoformaaconditioningfilm,termed“theacquiredpellicle”.The

filmiscomposedofavarietyofglycoproteins(mucins)andantibodies.Bacteriaadhere

variablytothiscoatedsurface.Behaviorsofbacteriachangeoncetheybecomeattached

tothesurfacesandthebacteriamassincreasesduetocontinuedgrowthandadhering

organisms,newadhesionandsynthesisofpolymers.Completelyanaerobicconditions

emergeinthedeeperlayer.Primarycolonizationisdominatedbyfacultativeanaerobic

Gram-positivecocciandplaquecollectedwithin24hoursmainlyconsistsofstreptococci

(S. sanguis). In the next phase, Gram-positive filaments (Actynomices) are the

predominant species. Veillonella, fusobacteria and other anaerobic gram-negative

bacteria can attach due to the surface receptors despite of the poor ability to bind

themselves to the first layer. Due to the difference of local environmental factors,

structurally different types of plaque evolve at different locations. In summary,

immediately following the immersion of hard, non-shedding surfaces into the fluid

environmentoftheoralcavity,adsorptionofmacromoleculeswillleadtoformationofa

biofilm.Fig.16

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Fig.16Schematicrepresentationofthedifferentstagesintheformationofdentalbiofilms.a)Pellicle

formsonacleantoothsurface.Bacteriaaretransportedpassivelytothesurface.b)attachment

becomesmorepermanentthroughspecificstereochimicalmolecularinteractionsbetweenbacterium

andpellicleandsecondarycolonizersattachtothealreadyattachedprimarycolonizers.C)growth

resultsinbiofilmmaturation.

53

1.2.5.1.3 Dentalcalculus

Dentalcalculusconsistsofmineralizedbacterialplaque.

Thedegreeofcalculusformationisnotonlydependentontheamountofpacterialplaque

presentbutalsoonthesecretionofthesalivaryglands(80).Supragingivally,calculuscan

berecognizedasacreamy-withishtodarkyellow/brownishmassofmoderatehardness.

Subgingivally,instead,maybefoundbytactileexplorationonly,sinceitsformationoccurs

apical to thegingivalmargin.Plaquemineralizationvariesgreatlybetweenandwithin

individualsalsowithindifferentregionsoftheoralcavity,andevidenceofmineralization

mayalreadybepresentafterfewdays(81).Supragingivalplaquebecomesmineralized

salivaandsubgingivalplaqueinthepresenceofinflammatoryexudateinthepocket.Itis

evidentthatcalculusrepresentsasecondaryproductofinfectionandnotaprimarycause

of periodontitis but it has to be realized that calculus is always covered by an

unmineralized layer of viable bacterial plaque. It has been established that calculus

roughness alone do not initiate gingivitis but can provide an ideal surface to further

plaqueaccumulationandsubsequentmineralization(82).

1.2.5.1.4 Periodontalpathogens

Thecriteriafordefiningpathogensofdestructiveperiodontaldiseaseinitiallywerebased

onfirstandsecondKoch’spostulate:

1. theagentmustbeisolatedfromeverycaseofthedisease

2. it must not be recovered from cases of other forms of disease or non-

pathogenically

Thesecriteriaincludeassociation,elimination,hostresponse,virulencefactors,animal

studiesandriskassessment.However,microbiologistsdonotexpecttofindthepathogen

in“allcasesofthedisease”becausetheycannotcurrencydistinguish“allcasesofagiven

disease”.Thecriterionofeliminationisbasedontheconceptthateliminationofaspecies

shouldbeaccompaniedbyaparallelremissionofdisease.Ifaspeciesiseliminatedby

treatment and the disease progresses, or if the level of a species remains high or

54

increases ina siteand thedisease stops,doubtwouldbecaston the species’ role in

pathogenesis.

The World Workshop in Periodontology (1996 Consensus Report) designated A.

actinomycetemcomitans, P. gingivalis and T. forsythia as periodontal pathogens. The

consensus summary, nowadays, is by no means exhaustive but does indicate that a

growingliteraturesuggestssomereasonablecandidatesasetiologicagentsofdestructive

periodontaldisease.

Thevirulenceofamicrobialpathogenisgenerallydefinedasthedegreeofpathogenicity

orabilityoftheorganismtocausediseaseasmeasuredbyanexperimentalprocedure.It

represents a combination of highly complex parameters and depends upon both the

relativeinfectivityoftheorganismandtheseverityofthediseaseproduced.However,

thesetwoparametersofinfectivityanddiseaseseverityareprofoundlyinfluencedbythe

natureandstatusofthehostorganismorthesiteofcolonizationinthathost.Forthis

reason, a breach in the normal defensive barriers of the host such as, trauma,

immunosuppression, coinfection can increase the virulence of a given organism. The

virulencedeterminantofapathogencansimplybedefinedasthosegeneproductswhich

facilitatecolonization,growth,andsurvivalwithinthediseasedhostorganismandspread

toanewhost.Anemergingkeypropertyofthesepathogens istheabilitynotonlyto

overcomehostdefensebutalsotomanipulatethesesystemstotheirownadvantage.

Oneexampleofthisuniquefeatureistheabilityofbothgram-negativeandgram-positive

bacteriaA.actinomycetemcomitansandP.gingivalistoinfluencethepatternofcytokines

expressionsbyhostcells(83).

Aggregatibacter actinomycetemcomitans: one of the clearest associations between a

suspected pathogen and destructive periodontal disease is provided by A.

actinomycetemcomitans.Aaisasmall,non-motileGram-negativerodthatformssmall

colonies(84).Itwasdemonstratedthatthemajorityofsubjectswithlocalizedaggressive

periodontitishadanenormouslyelevatedserumantibodyresponsetothisspecies(85).

Aa has been shown, in vitro, to have the ability to invade cultured human gingival

epithelialcells,humanvascularendothelialcells,andbuccalendothelialcellsinvivo(86).

Aahasalsobeenimplicatedinadultformsofdestructiveperiodontaldisease,butitsrole

55

islessclear.Thisspecieshasbeenisolatedinchronicperiodontitisbutlessfrequentlyand

inlowernumbersthenfromthelesioninAggressiveperiodontallesionssubjects(87).

Porphiromonasgingivalis:isasecondconsensusperiodontalpathogenthatcontinuesto

be investigated. Pg is a non-motile Gram-negative anaerobic rod that forms black to

browncolonies.Membersofthisspeciesproducecollagenase,gingivalpain,anarrayof

protease thatdestroy immunoglobulins,hemolysins, endotoxin, fattyacids, ammonia,

hydrogensulfideetc.StudieshavestrengthenedtheassociationofPgwithdiseaseand

demonstratedthatthespeciesisuncommonandinlownumbersinhealthorgingivitis

butmorefrequentlydetectedindestructiveformofdisease.Pghasbeenalsoshownto

induceelevatedsystemicandlocalimmuneresponsesinsubjectswithvariousformsof

periodontitis (88). LikeAa, Pg has beendemonstrated, in vitro, to have the ability to

invade cultured human gingival epithelial cells, human vascular endothelial cells, and

buccalendothelialcellsinvivo(86).

Tannerellaforsythia:Tfwasdescribedasthethirdperiodontalpathogeninlate70’s(89).

TheorganismisaGram-negative,anaerobic,spindle-shapedrod.Frequentlyisassociated

withF.nucleatuminsubgingivalsites(90).AfeatureofTfisthepresenceofaserratedS-

layerthathasshowntomediateepithelialcells invasionandto inducecellsapoptosis

(86).Thispathogenwasthoughttobeuncommonbutfurtherstudieswithmonoclonal

antibodieshavedemonstratedthatismorecommonthanpreviouslyfoundanditslevels

were strongly related to increasing pocket depth. In addiction Tf was found more

frequently and in higher numbers in actively progressing periodontal lesions than in

activelesions(91).

1.2.5.1.5 Themicrobialcomplexes

Theassociationofbacteriawithinmixedbiofilmisnotrandom,ratherthereare

aspecificassociationsamongbacterialspecies.Thepresenceofspecificmicrobial

groupswithindentalplaquehasbeendemonstrated(90).

Sixcloselyassociatedgroupsofbacterialspecieswererecognized(4earlycolonizers

and2predominantlyGram-negativeperiodontalpathogenscomplexes):

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- SpecificspeciesofActinomyces

- Yellowcomplex,consistingofmembersofthegenusStreptococcus

- Greencomplex,consistingofCapnocytophagaspecies,A.

actinomycetemcomitansserotypea,E.corrodensandCampylobacterconcisus

- Purplecomplex,consistingofV.parvulaandActinomycesodontolyticus.

- Orangecomplex,consistsofCampylobactergracilis,C.rectus,C.showae,E.

nodatum,F.nucleatum,F.periodonticum,Pe.Micros,Pr.Intermedia,Pr.

nigriscensandS.costellatus.

- RedComplex,consistingofT.forsythia,P.gingivalisandTreponemadenticola.

Thelasttwocomplexesarecomprisedofthespeciesthoughttobethemajoretiologic

agents of periodontal diseases. It is of primary importance to know that the

microorganismshaveaneffectontheirhabitat,theperiodontaltissues,andthehabitat

hasamajoreffectonthecomposition,metabolicactivities,andvirulencepropertiesof

the colonizing microorganisms. Thus, modifications of the supra- and sub-gingival

microbiota certainly affect the outcome, periodontal health or disease. Moreover,

changesinthehostor localhabitatalsoaffectthecompositionandtheactivityofthe

microbiota.

Perhapsthemostinfluentialfactoronthecompositionofthesubgingivalmicrobiotais

theperiodontaldiseasestatusofthehost(92).Themajordifferencebetweenhealthand

disease, on average, was the increase counts, proportion and prevalence of the red

complexspecies,T.forsythia,P.gingivalisandT.denticolainsubjectswithperiodontal

disease.Fig.17

Inaddition,otherputativeperiodontalpathogensoftheorangecomplexwerealsomore

prevalent and in higher levels in periodontitis subjects. However, individuals with

differentformofthediseasehavedifferentsubgingivalmicrobialprofiles.Evensubjects

withthe“same”periodontaldiseaseintermofbothclinicalappearanceandseveritycan

exhibitquitedifferentsubgingivalmicrobiotas.

Inconclusion,ifthebiofilmisnotdisruptedfrequentlyandisallowedtoaccumulate,the

conditionswithin itstarttofavorbacterialspecies,suchasFusobacteriumnucleatum,

57

thatare capableof sensingand influencing theirenvironmentbyemploying chemical

cues. Such ‘quorum-sensing’ organisms start to emerge and elicit a stronger host

response, which, in turn, can lead to the development of gingival inflammation and

increasethesupplyofcertainnutrients thatencouragetheproliferationof traditional

pathogenssuchasPorphyromonasgingivalis.

1.2.5.2 PATHOGENESISOFPERIODONTALDISEASE

Theclassicalmodelofperiodontaldiseasepathogenesis,developedbyPageeKornman

in1997(Fig.18)providesakeyframeworktounderpinstudiesaimedatunravelingthe

complex interdependent relationships that exist both within the plaque biofilm and

betweenthebiofilmandthehostresponse.Wenowrecognizethatapathogenicbiofilm

isanecessaryprerequisiteforperiodontitistodevelopbutinitselfisinsufficienttocause

Fig.17a)Associationamongsubgingivalspecies.Thedifferentcolorsinthepyramidrepresentdifferent

bacterialcomplexeswhicharefrequentlydetectedinassociationwithoneanother.Thebaseofthepyramid

representstheearlystageofplaquedevelopment,whereastheapexcontainsthoseorganismsthoughtto

bethelastspeciestobecomeestablishedinthemicrobiota.b)PiechartsofthemeanpercentageDNAcount

ofmicrobialgroupsinsupragingivalplaque.

58

thedisease(93).Diseaseresultsfromcomplexinteractionsbetweenthebiofilmandthe

inflammatoryimmuneresponse,anditisthelatterthatisestimatedtoaccountfor

almost80%oftheriskofperiodontaltissuedamage(94).

Theperiodontitisphenotypeischaracterizedbyanexaggerated,yetpoorlyeffectiveand

non-resolving,inflammationoftheconnectivetissuessupportingtheteeththatleadsto

tissue destruction, rather than a specifically targeted, effective and self-resolving

inflammatoryimmuneresponse.Oneofthekeychangesinresearcherperceptionsofthe

infectiousimmunecondition,whichitiscallperiodontitis,istherealizationthatretaining

orattainingclinicalhealth requiresahealth-promotingbiofilmwithinwhichsymbiotic

relationshipsexistbetweenmicroorganismsandwiththehostresponse.

Moreover,insusceptiblepatients,incipientdysbiosiscantriggeraninappropriate,and

frequentlyexcessive,hostresponse,inwhichexcesscytokines,reactiveoxygenspecies

(oxidative stress) and matrix metalloproteinases are generated and overwhelm their

respective antagonists, resulting in collateral periodontal tissue damage. the chronic

inflammatory state is characterizedbyattemptsathealing (angiogenesis and fibrosis)

Fig.18ClassicalmodelofPage&Kornman,showinghost–microbeinteractionsinthe

pathogenesisofperiodontitis.LPS,lipopolysaccharide;MMPs,matrixmetalloproteinases;

PMNs,polymorphonuclearneutrophils.

59

arising at the same time as inflammation, creating a rich nutritional environment for

sustainingthedysbiosisandthusthepathogenicbiofilm.

The colonizing microbes on mucosal surfaces, together with dangerous endogenous

signaling molecules, such as extracellular ATP or extracellular DNA, activate the

inflammasome,resultinginthesubsequentsecretionoftheproinflammatorycytokines

interleukin-1betaandinterleukin-18.Inflammasomeactivationismediatedbycaspase-1

activity,whichalsohasanimportantroleintheactivationofcellularapoptosis.Reactive

oxygenspeciesarealsorequired,andindeedperiodontitisischaracterizedbyoxidative

stress,providingfurtheropportunitiesforinflammasomeactivation,whichmayresultin

positivefeedback,impactinguponthehostresponseaswellasonthechronicityofthe

inflammation (95). The release and secretion of proinflammatory cytokines activates

polymorphonuclear leukocytes (neutrophils), which express various cell-surface

receptorsthatbindtochemotacticstimuliandinitiatedownstreamsignalingsequences

thatleadtocomplexreactionsandevents,includingcytosolicactinreorganization,shape

changesanddevelopmentofcellularpolarity.Thereleaseofhistamineandtheactivation

of complement components C3a and C5a leads to vasodilatation, increased vascular

permeability and slowing of blood flow within the respective capillary beds. The

neutrophilsthenfalloutofmildstreambloodflowandcontactthevascularendothelium,

wheretheymarginateandrollontheendothelialsurfaceofthecapillariesbeforebinding

firmly,viaintergrinreceptors,andmovingoutofthebloodvessels intothetissuesvia

diapedesis.Neutrophilsbelongtothefastest-movingmammaliancells,andonceinthe

tissuestheymigratealongachemotacticgradientthatenablesthemtolocatethesiteof

infectionandrespondviareceptormediatedphagocytosisandsubsequentintracellular

killingoftheingestedbacteria(96).

A major role in this process is played by the lectin site of the leukocyte b2-integrin

receptor (also knownasCR3,Mac-1 andCD11b/CD18). Reports suggest that another

potentiallyimportantreceptor(delineatedfromothermyeloidcells),lipopolysaccharide

receptor (CD14), is only found in an inactive form. Eventually stored within the

neutrophil,CD14becomesexpressedontheoutercell-membranesurfaceunderextreme

conditions.Togetherwithneutrophildiapedesisandchemotacticmigrationtowardthe

60

siteofbacterialinfection,localcapillariesalsoreleaseanenhancedamountofserumas

a result of the effects of histamine and complement C3a and C5a upon vascular

permeability.Theincreasedtissuefluidcausesthetissuestoswellandalsoincreasesthe

exudationofgingivalcrevicular fluid.Somepathogensareabletoextendandprolong

theseinflammatoryreactionsinordertoguaranteeacontinuoussupplyofhost-derived

nutrients.

Neutrophilactivationleadstophagocytosisandintracellularkillingofmicroorganisms,as

well as to the release of enzymes, whichmay contribute to local tissue destruction.

Enhancedreleaseofelastaseandotherproteinases,suchascollagenase,resultsinthe

depolymerizationoftissuecollagenfibers,thusincreasinglocaltissuepermeability.Fig.

19

Fig.19Contemporarymodelofhost–microbeinteractionsinthepathogenesisofperiodontitis,inwhichthehost

responsedrivesanincipientdysbiosis(gingivitis).Ifthebiofilmisnotdisrupted/removed,frankdysbiosisresults

andperpetuatesachronicnonresolvinganddestructiveinflammation.DAMPs,damage-associatedmolecular

patterns;fMLP,N-formylmethionyl-leucyl-phenylalanine;GCF,gingivalcrevicularfluid;LPS,lipopolysaccharide;

MMPs,matrixmetalloproteinases;PMNs,polymorphonuclearneutrophils.

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1.2.6 RISKFACTORSFORPERIODONTITIS

Thereisanabundanceofbothempiricalevidenceandsubstantialtheoreticaljustification

foracceptingthewidespreadbeliefthanmanydiseaseshavemorethanacause,inother

wordstheyhaveamultifactorialetiology(97).Consequently,inanyparticularinstance

when a causal relationship is investigated, the specificity of the relation between

exposure to an etiological agent and effect (the necessity or the sufficiency of the

condition)maybechallenged.Inthecaseofperiodontaldiseases,itisknownthatthe

presenceofthemicrobialagent(whichisdefinedasanecessarycondition)isnotalways

accompaniedbysignsorsymptomscharacteristicofthatdisorder.Thecausalinference,

theprocessofdrawing conclusions related to the causeof adisease, is aparticularly

complexissueinepidemiologicresearch.Hillin1971formalizedthecriteriathathaveto

befulfilledinordertoacceptacausalrelation(98):

- Strengthofassociation:thestrongertheassociationbetweenputativeriskfactor

andthedisease,themorelikelyitisthattheanticipatedcausalrelationisvalid.

- Dose-responseeffect:theobservationofthefrequencyofthediseaseincrease

withthedoseofexposuretoafactor

- Temporal consistency: to establish if the exposure to the causative factor

occurredpriortothedisease

- Consistencyoffindings:ifseveralstudiesaboutthesamerelationshipshowthe

sameresults.

- Biologicplausibility:iftherelationshipshouldmakesenseinthecontestofcurrent

biologicknowledge.

- Specificityoftheassociation:iftheinvestigatedfactorisfoundtobeassociated

withonlyonediseaseandviceversa.

Inthecontestofperiodontitis,numerouscross-sectionalstudiesidentifyingpotentialrisk

factors are available, but a relatively limited number of longitudinal studies involve a

multivariateapproachtotheidentificationofexposuresofinterestwhilesimultaneously

controllingfortheeffectofpossibleconfounders.AreviewbyBorrellandPapapanou,

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hasmadeadistinctionbetweenputativefactorsthatarenotamenabletointervention

(non-modifiablebackgroundfactors)andmodiafiablefactors(environmental,acquired,

andbehavioral)(99).

1.2.6.1 NON-MODIFIABLERISKFACTORS

1.2.6.1.1 Age

The relationshipbetweenperiodontitisandage is complex,even if it is clear that the

prevalenceofperiodontaldiseaseincreaseswithage(100).Someauthorschallengethe

relationship considering the “age effect” as the cumulative effect of the prolonged

exposure to true risk factors (101). The association between periodontitis and age

appearstobedifferentforpocketdepthandamountofclinicalattachmentloss.While

thereisapronouncedeffectofincreasingattachmentlosswithage,theeffectonpocket

depth is minimal (102). Since periodontitis is a microbially-induced inflammatory

disorder, an age-dependent alteration in innate immunity likely contribute to more

pronouncedperiodontalpathologyinelderlyindividuals.Inconclusion,anage-related,

ratherthananage-dependent,increasedsusceptibilitytoperiodontitisinolderpeopleis

biologicallyplausible.

1.2.6.1.2 GenePolymorphisms

Evidence of genetic predispositions of certain individuals has been documented in

classicaltwinandfamilystudies.Anassociationbetweenacompositegenotypebasedon

specificpolymorphismsintheinterleukin1(IL-1)geneclusterandsevereperiodontitisin

non-smokers has been reported (). Similar work has investigated polymorphism in

additionalinflammatorygenes,includingthetumornecrosisfactor(TNF)gene,theIL-6

gene,TheIL-4andtheIL-10gene.(103,104)

The majority of cross-sectional studies report positive associations between the

investigatedpolymorphismsandtheextendandtheseverityofperiodontitis.However,

theseresultsarenotconsistentacrosspopulationsandbetweenethnicgroups(105).The

resultsoffewlongitudinalstudiesarealsoconflicting.Nevertheless,Langhasconcluded

63

thatIL-1genotype-positivepatientshaveageneticallydeterminedhyper-inflammatory

responsethat isexpressedclinically intheperiodontaltissuesas increasedprevalence

andincidenceofBOPduringmaintenance(51).

Inconclusion,thereisinsufficientepidemiologicevidencetoestablishapolymorphismas

trueriskfactorforperiodontitis(106)

1.2.6.2 MODIFIABLEENVIRONMENTAL,AQUIREDANDBEHAVIORALFACTORS

1.2.6.2.1 Specificmicrobiota

Theassociationbetweenhigh levelsof colonizationby specificperiodontalpathogens

andtheprogressionofperiodontaldiseasehasbeencorroboratedbylongitudinaldata

in untreated population (see Etiopathogenesis of periodontal disease chapter).

Collectively,Datageneratedinthepastdecadeshaveenhancedourknowledgeofthe

roleofspecificperiodontalbacteriaasriskfactorforperiodontitisandhaveclarifiedthat

theintensityoftheexposuretothespecificmicrobiotaratherthanthepresenceofthe

pathogenisanimportantdeterminantoftheclinicalphenotype.Moreover,thevirulence

ofthepathogen,anditsabilitytocauseperiodontaltissuedamageandconferriskfor

diseaseprogressionmaybeentirelydifferentamongvariousclonaltypeswithinasingle

species.Ontheotherhand,pathogeneliminationfromthesubgingivalmicrobiotaresults

inimprovementsinclinicalperiodontalstatus.Aswidelydemonstrated,anantimicrobial

approach, including removal of subgingival plaque with or without the adjunct of

antibioticsorantiseptics,followedbyanadequatemaintenanceprotocol, isthesingle

mostsuccessfulandconsistentstrategyinthetreatmentofperiodontitis(107).

1.2.6.2.2 Smoking

Theassociationbetweentobaccosmokingandperiodontitiswasfoundedonthebroad

effects of multiple tobacco-related substances on cellular structure and function.

Smokinghasbeen shown toaffect thevasculature, thehumoral andcellular immune

64

responses, cell signaling processes, and tissue homeostasis (108). It is important to

underlinethattheinferiorperiodontalstatusofsmokerscannotbeattributedtopoorer

plaquecontrolormoreseveregingivitis.Infact,smokingcontributestotheformationof

adysbioticbiofilm,differentfromthenon-smokerbiofilm,characterizedbyahigherlevel

ofcolonizationbyperiodontalpathogens.Studiesexaminingtheeffectsofsmokingon

theoutcomeofperiodontaltreatmenthavedemonstratesthattreatmentresponsesare

modifiedbycigaretteconsumption,withcurrentsmokersexhibitingpoorer responses

thanformerorneversmokers(109).Thesestudieshaveconfirmedthenegativeeffectof

smokingon theoutcomeof severalperiodontal treatmentsmodalities, includingnon-

surgical, surgical, and regenerative periodontal therapy (110). In contrast, smoking

cessationwasshowntohavebeneficialeffectonperiodontalstatus.

Inconclusion,cigarettesmokingappearstofulfillthemajorityoftherequiredstepsof

theriskassessmentprocessstipulatedbyBeckandisconsideredoneofthemajorrisk

factorsforperiodontitis.

1.2.6.2.3 DiabetesMellitus

Theroleofdiabetesmellitus(DM)asariskfactorforperiodontitishasbeendebatedfor

decades(111).TheadverseeffectofDMonperiodontalstatusappeartobeparticularly

pronounced in subjectwith a longdurationofDMandpoormetabolic control (112).

Studieshaveprovidedevidenceofadose-responserelationshipbetweenpoormetabolic

controlandtheseverityofperiodontitis.Theoutcomeofperiodontaltreatmentinwell-

controlleddiabeticpatientsissimilartothatofnon-diabeticsubjects,whilepatientwith

poorlycontrolledDMdisplayaninferiortreatmentoutcome(113).

Severalstudiessuggestatwo-wayrelationshipbetweenDMandperiodontitis.Beyond

theobservedincreasedseverityofperiodontaltissuedestructioninsubjectswithDM,

studiesindicateahigherincidenceofDMcomplicationsandpoorermetaboliccontrolof

diabetesinperiodontitispatients.

65

1.2.6.2.4 Obesity

Theplausibilityofapotentiallinkbetweenobesityandperiodontitishasbeensuggested

to involve a hyper-inflammatory state and an aberrant lipidmetabolism prevalent in

obesity,aswellasthepathwayofinsulinresistanceallofwhichmaycollectivelyresultin

anacceleratedbreakdownoftheperiodontaltissues(114)

Anumberofstudieshaveindicatedapositiveassociationbetweenobesity,definedas

bodymassindex(BMI)>30kg/m2,andperiodontitis.It is importanttoknowthatthe

majorityofthepublicationiscross-sectional,andthusdonotfacilitateinterferenceson

temporalityormechanisms, and theavailableeoidemiologicdata are limitedandnot

universally consistent, additional research on the role of obesity in periodontitis is

warranted.

1.2.7 PERIODONTITISANDOSTEOPOROSIS

Likewiseosteoporosis,periodontitisisasilentdisease,whichoftenremainsundiagnosed

untillate,whenteethbecomelooseoranabscessdevelops.Interestingly,bothdiseases

alsosharesomeriskfactors,suchasoldage,smoking,anddiseases/medicationsthatmay

interferewithosseoushealing (115). As a consequence, several studies have tried to

investigate if these two diseases are linked and if osteoporosis can be considered a

predisposingfactorforthedestructionofperiodontalsupport.

Early cross-sectional studies of limited sample size and largely confined to post-

menopausalwomen, have suggested thatwomenwith low bonemineral density are

more likely to have gingival recession and/or pronounced gingival inflammation and

clinicalattachmentloss(116).

A radiographic study by Pearson in 2002 reported a positive association between

osteoporosisandperiodontitiswithasignificantORof1,8(95%CI1,2–2,5).However,

studiesthathavefailedtodemonstratethecorrelationhavealsobeenpublished(117).

66

Basedon theseobservation, it hasbeenhypothesized that the systemic loss of bone

densityinosteoporoticpatientsmay,incombinationwithotherfactors,provideahost

system that is increasingly susceptible to inflammation-associated destruction of the

periodontaltissues(118).Overallthedatafromlongitudinalstudiesareconflicting,infact

somestudiesreportapositiveassociationbetweenosteoporosisandclinicalattachment

lossinwomenwithsubgingivalcalculusbutnotifthecalculusweresupra-gingival(119).

Intheseavailablestudies,osteoporosiswasdiagnosedbyapplyingdifferenttechniques,

goingfromtheoldsingleanddualphotonabsorptiometry,tosingleordualX-rayenergy

absorptiometry tha is the actual WHO gold standard, to ultrasound or quantitative

computerized tomography. On the other side, periodontitis was assessed either

radiographically, by measuring alveolar bone resorption, or clinically, by measuring

clinical attachment loss or tooth loss. It is therefore intuitive to understand how

heterogeneous the publications are and how difficult it is to draw meaningful

conclusions.Morerecentsystematicreviewsoftheavailablestudiesonosteoporosisand

periodontitisconcludedthattherelationshipbetweentwoconditionscouldbeplausible

butisstillunclear(118).

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1.3 OSTEOPOROSISANDJAWBONES

1.3.1 SYSTEMICANDJAWBONELOSS

It is plausible to hypothesize that osteoporotic-induced systemic bone loss may also

includebonelossatthejaws.Pre-clinicalstudiesinovariectomizedanimalsreportedthat

oestrogendeficiencycoulddetermineadecreaseinbonevolumeandalterationsinthe

trabecularstructureofthemandibularcondyle(120,121),intheinter-radicularseptaof

molaralveolarbone(122,123),anincreaseinmandibularcorticalporosity(124)anda

reduction inmineralizationdensity,osteocyte lacunae,andosteocytenuclearnumber

(125).

Someclinical studies suggested that there isan increasedalveolarbone resorption in

osteoporotic versus non-osteoporotic edentulous patients (126, 127), and that

medications affecting systemic bone density (like hormone replacement therapy and

bisphosphonates) are associatedwith a slower loss of alveolar bone (128). However,

otherclinicalevidencesdidnotconfirmtheinfluenceofsystemicbonemineraldensity

ontheresorptionofedentulousjaws(129-131).Severalclinicalstudiesinvestigatedthe

relationshipbetweenbonedensitymeasuredindifferentsystemicskeletalsitesandin

thejawbonesinsubjectswithdifferentTscores.Althoughmanyofthesestudiesfounda

positive correlation (132-139), others reported that jawbone density is only partially

correlatedtothedensityinotheranatomicsites(140-142).Therearealsosomelimited

evidencesthatdidnotfoundanydifferences in jawbonedensitybetweennormaland

osteopenic/osteoporoticsubjects(143,144).Theheterogeneitybetweentheavailable

studiesmayhavecontributedtotheseconflictingresults.Infact,differenttechniquesto

measurebonedensitywereadopted,dentateandedentulousareaswereoftenpulled

together and populations with different demographic characteristics were evaluated

withoutaccountingfortheseimportantconfoundingvariables.

Despite the contrasting results, during the past two decades, several studies have

evaluated the accuracy of different quantitative and qualitative indices calculated on

68

dentalradiographs(OPG) in identifyingpatientswithreducedskeletalBMD(145-150).

Amongstthelinearindices,thefollowingarethemostpopularones:

1) Mandibular corticalwidth (MCW) ormental index (MI) ormandibular cortical

thickness(MCT):Itisusuallymeasuredinthementalforamenregion,alongaline

passingthroughthemiddleoftheforamenandperpendiculartothetangentto

thelowerborderofthemandible(151).

2) Panoramicmandibular index (PMI): It is the ratio between theMCW and the

distancefromthelowerbordertotheinferioredgeofthementalforamen(152)

3) Antegonial index (AI): It is themandibular thicknessmeasured at the anterior

borderoftheramus(153)

4) Gonialindex(GI):Itisthemandibularthicknessmeasuredattheposteriorborder

oftheramus(154).

5) Mandibularratio(M/M):Itistheratiobetweenthetotalheightofthemandibular

bodyandtheheightfromthelowerborderofthemandibletothelowerborder

ofthementalforamen(155)

Amongstthequalitativemorphometricparameters,theKlemettiindex(KI)isbyfarthe

mostwidelyadoptedindex.TheKI,alsoknownasmandibularcorticalindex,classifiesthe

mandibularcortexdistaltothementalforameninthreecategories:

• C1,whentheendostealmarginisevenandsharp;

• C2,whentheendostealmarginpresentslacunarresorptionorcorticalresidues

ononeorbothsides;

• C3,whenthere isaclearlyporouscortical layer,withheavyendostealcortical

residues(156)

69

Fig.20A)Quantitativeindices:MCW=b;PMI=b/a;GI=d;AI=e;M/M=c/a

(B)Klemettiindex(orMCI)

70

2 HYPOTHESISANDAIMOFTHERESEARCH

71

2.1 BACKGROUNDANDHYPOTHESIS

Osteoporosisisoftenreferredtoasa“silentdisease,”sincequiteoftenitisnotdiagnosed

until a fragility fracture occurs. Osteoporotic fractures are expected to occur in

approximatelyone intwoCaucasianwomenandone infivemen,thusrepresentinga

worldwideburdenwithanassociatedhighmorbidityandmortality.Themeasurementof

bonemineraldensity(BMD)atthefemurneckandlumbarspinewithdual-energyX-ray

absorptiometry(DXA)isthegoldstandardforosteoporosisdiagnosis.Althoughthereis

indirectevidencethatsupportsthescreeningofpopulationgroups(mainlywomen>65

yearsold)toreducetheriskoffracturesbyidentifyingandtreatingpeoplewithreduced

BMD,inmostcountriesthecostofageneralscreeningprogrammeisnotaffordableor

cost effective. As a consequence, osteoporotic patients are often undiagnosed or

untreatedforlongperiodsoftime.Remarkably,only23%ofwomen>67yearsoldwho

have experienced an osteoporosis-related fracture receive either a BMD test or an

osteoporoticmedicationinthesixmonthsafterthefracture,asreportedbytheNational

CommitteeforQualityAssurance(NationalCommitteeforQualityAssurance2014).

Considering that dental panoramic radiographs (OPGs) are frequently performed for

diagnostic purposes during dental check-ups or before several dental procedures

(Tugnait, Clerehugh et al. 2003), it would be of great value if they could be used in

identifyingpatientsatriskofosteoporosis.Theideaisthatdentistscouldpotentiallyspot

previouslyundiagnosedosteoporoticpatients and refer them to the specialist,where

theycouldbetreatedbeforedevelopingafracture.

Periodontitisisachronicinflammatorydiseasethataffectsthesupportingtissuesofteeth

(periodontalligament,gumandbone)and,ifuntreated,caneventuallyleadtotoothloss.

AccordingtotheNationalHealthandNutritionExaminationSurvey (NHANES),46%of

adultspresentedwithperiodontitisinUSin2009to2012,thusaccountingfor64.7million

people, with 8.9% of them presenting severe periodontitis. The demonstration of a

relationship between osteoporosis and periodontitis is difficult, especially in

considerationofthefactthattheyaremultifactorialdiseasesandthatthecommonrisk

72

factorsmay introduceadditionalbiases.Although several cross-sectional studieshave

reportedanassociation.

2.2 AIMOFTHESTUDY

2.2.1 PRELIMINARYLITERATUREREVIEWS

1. Todoanarrativereviewontheavailableevidenceonthecorrelationbetween

skeletalandjawbonedensityinosteoporoticsubjects

2. Todoanarrativereviewontheavailableevidenceonthecorrelationbetween

periodontitisandosteoporosis

2.2.2 PRIMARYOUTCOMES

3. To assess the feasibility of using dental panoramic indices to screen for post-

menopausalosteoporosis

4. To assess the sensitivity and specificity of Klemetti Index (KI) to screen for

osteoporosisinpostmenopausalwomen

5. To assess the sensitivity and specificity of quantitative panoramic indices

(Mandibular Cortical Width and Panoramic Mandibular Index) to screen for


6. To assess the precision and reproducibility of panoramic indices to screen for


73

2.2.3 SECONDARYOUTCOMES

7. To assess a statistical significant correlation between periodontitis and

osteoporosis

74

3 LITERATUREREVIEWS

75

3.1 SYSTEMICMINERALBONEDENSITYANDJAWBONES

Recently,Calciolarietal(Calciolari,Donosetal.2015)conductedasystematicreviewof

theliteratureandmeta-analysisontheaccuracyofpanoramicmorphometricindicesin

detecting reduced BMD. 50 studies meeting the inclusion/exclusion criteria were

includedinthequalitativeevaluation,buttheriskofbiasassessment(performedwith

theQUADAS-2tool)revealedthatagreatpartofthestudieswasnotofhighquality.In

particular, methodological concerns were associated to the index test and patient

selection domains, as several studies did not report clearly the patients’

inclusion/exclusion criteria, they did not state if the examiners were blinded to the

patients’ skeletal BMD or they did not measure intra/inter observer agreement. 19

studieswereeventuallyincludedinthemeta-analysis,whichcouldbeperformedonlyfor

three indices: MCW, PMI and KI. Within the limitations of this review, the authors

concludedthatPMIwithacut-offvalueof0.3seemedthemostaccuratelinearindexto

screenforreducedBMD(sensitivityandspecificityabove70%).Lessstrongconclusions

couldbedrawnforMCW,butthisindexseemedmoreusefultoexcludetheriskoflow

BMD,since in90%ofthecasespatientswithacorticalwidthwiderthan4mmhada

normalskeletalBMD.Thequalitativeevaluationofmandibularcorticalerosions(KI)was

also found to be a useful and reliable indicator of reduced skeletal BMD, since in

approximately80%ofthecasesitwasassociatedwithatleastosteopenia.

Asnopanoramicindexwith100%sensitivityandspecificityhasbeenidentifiedyet, in

some studies it has also been proposed to combine different indices between them

(Klemetti,Kolmakovetal.1994,Miranda,Aritaetal.2012)orwithwell-knownclinical

riskfactorsforosteoporosis(suchasBMI)(Horner,Devlinetal.2002).

SincethesystematicreviewbyCalciolarietalhasincludedstudiestillMarch2014,the

samesearchstrategyhasbeenusedinOctober2018toupdatetherecentreviewwith

theliteratureofthelastfouryears.

The applied research strategy included terms related to the population and the

interventioninvestigatedandhasbeenperformedintwodatabases,MEDLINEviaOVID

andEMBASE,updateinOctober2013.

76

No language restrictions have been applied. The search strategy for MEDLINE and

EMBASE have used a combination of MeSH terms and text words which have been

combinedasPopulationANDIntervention.Tab.3

MEDLINEviaOVID Meshterms Free-textsearch LimitsPopulation bonedisease,

metabolic/orexpbonedemineralization,pathologic/orexposteoporosis

osteoporo$ ORosteopeni$

NOT (animals NOThumans)

Intervention/Exposure BoneDensityORexpDensitometryexpJawORexpJawEdentulous

(bone adj2 densit$) OR(bone adj2 content) ORbmd OR bmc ORdensitometr$jaw$ OR mandib$ ORmaxill$oredentul$

EMBASE Emtreeterms Free-textsearch LimitsPopulation exp.osteoporosis

ORosteopeniaosteoporo$ ORosteopeni$

NOT (animals NOThumans)

Intervention/Exposure BoneDensityORBonedensitometryJawOREdentulousness

(bone adj2 densit$) OR(bone adj2 content) ORbmd OR bmc ORdensitometr$jaw$ OR mandib$ ORmaxill$oredentul$

Tab.3Searchstrategy

Due to the large volumeof literatureon this topic, a three-stage screeninghasbeen

appliedto increasetheprecisionofscreening.All stages (titles,abstract, full-text)has

beencarriedoutbythereviewer.Atthestageoffull-textscreening,adataextraction

formwascompletedtocheckeligibilityofthestudiesand,ifeligible,tocollectdetailed

informationaboutpopulation,interventionandoutcomes.

Sevenarticleshavebeenincludedinthe2018update,accordingtotheinclusioncriteria

ofthe2015reviewbyCalciolarietal.Alltheselectedpapershavedescribed:

- Totalnumberofpatientandthepartitioninhealthy,osteopenicandosteoporotic

- Almostonepanoramicindexusedforthepredictionofthebonemasscondition

77

- Thegroupsconsideredtobematchedforthecomparison

- At leastoneof these information: sensitivity, specificity,numberof false/true

negative/positive,ROCcurve.

TheindicesthathavebeenusedmostfrequentlytoscreenforreducedBMDhavebeen:

Mandibular cortical width (MCW): In the original revision, 34 studies reported

measurements of the width of themandibular cortex, which was referred to as the

mandibularcorticalwidth(MCW)ormentalindex(MI)ormandibularcorticalthickness

(MCT).Inmostofthestudies,MCWwasmeasuredinthementalforamenregion,along

a line passing through the middle of the mental foramen and perpendicular to the

tangent to the lower border of themandible eithermanually or digitally,with image

analysissystems.ThecutoffvalueswerechosenafterdrawingtheROCcurveinorderto

findthehighestsensitivity/specificityandtheyrangedfrom2.69mmto5mm.Thelevels

ofsensitivityandspecificityassociatedwiththis indexwereheterogeneousandhada

reciprocal relationship that varied in relation to the threshold chosen. A few studies

reporteda sensitivity>95% (157,158),while inother studies, thisparameterdidnot

reach20%(157,159).Thesamevariabilityappliedtothespecificitylevels.Theupdate,

hasshownthatinthearticlespublishedinthelastfouryears,theanalysisofthewidthof

themandibularcortexhasbeenreportedinallthearticles.Thecutoffvalueswerechosen

afterdrawingtheROCandranged from1.5mmto4mm.Similarly to the2015data,

sensitivity and specificity were heterogeneous. Carmo et al. (160) have reported a

sensitivity/specificity>95%,butotherstudies(161-164)haveshownlevels<70%.

Panoramicmandibular index (PMI): In the original revision, 9 studies considered the

panoramic mandibular index (PMI). This index represents the ratio between the

mandibularcorticalwidthatthementalforamenregionandthedistancefromthelower

bordertotheinferioredgeofthementalforamen(152).Mostofthestudiesreporteda

cutoffvalueof0.3,withlevelsofsensitivityandspecificityindetectingindividualswith

reducedbonedensity(Tscore<–1)rangingfrom40.8%to100%andfrom47%to88%,

78

respectively.Only1studyconsidered4differentcutoffs(159).OnlyonestudibyBaltoet

al.hasconsideredthePMIaspredictorofosteoporosis,reportingaAUCof0,591(161).

Klemettiindex(KI):Twenty-sevenstudiesconsideredtheKlemettiindex(KI)asatoolfor

predictionofreducedBMDaccordingtoCalciolarietal.(165)Thisindex,alsoknownas

themandibularcorticalindex,qualitativelyclassifiesthemandibularcortexdistallytothe

mentalforameninthefollowingcategories:C1,whentheendostealmarginisevenand

sharp;C2,whentheendostealmarginpresentslacunarresorptionorcorticalresidueson

oneorbothsides;andC3,whenthecorticallayerisclearlyporous,withheavyendosteal

corticalresidues.Intheincludedstudies,thepresenceofcorticalerosions(eitherC2or

C3 type)produceda sensitivity indetecting reducedBMD (T score<–1) ranging from

48.7% to 100% and a specificity ranging from 31% to 88.89%. The sensitivity in the

diagnosisofosteoporosis(Tscore≤–2.5)variedfrom35.9%to90.9%andthespecificity

from 7.8% to 93.9%. The wide range of outcomes reported is a sign of the high

heterogeneitybetweenthestudies.Onlyafewstudiesevaluatedtheaccuracyofclearly

erodedcortex(C3)indetectingosteoporosis(151,166,167).Onlyoneoftherecently

publishedarticleshasreporteddataonklemettiindex.InthepaperbyCarmoetal.the

presenceofcorticalerosions(eitherC2orC3type)producedasensitivity indetecting

reducedBMD (T score<–1)of 100%anda specificity of 90,1%. The sensitivity in the

diagnosis of osteoporosis (T score ≤–2.5) was 95% and the specificity was 98,9%

(160).Tab.4

79

Author(year)

TotalN.pts

N.Ost

N.Osp

N.Healthy

Age(y±SD)

Panoramicindex

Typemeasurement

Cutoff Groupsmatching

Sensitivity,%(95%CI)

Specificity,%(95%CI)

PPV,%(95%CI)

NPV,%(95%CI)

AUC(SE,95%CI)

Baltoetal.(2018)

431 75 124 232 57.78±6.24

MCW

Manualannotation

4.6mm Healthyvs.osp+ost

58.4 60.2 0.620(0.031,0.550-0.690)

4.1mm Healthy+ospvs.ost

69.4 68.4

PMI

Manualannotation

0.591(0.036,0.521-0.662)

M/M Manualannotation

0.592(0.041,0.512-0.672)

Carmoetal.(2017)

198W 20(lumbarspine)

101(lumbarspine)

77(lumbarspine)

53.1±5.0

KI

Visual C1vs.C2+C3

Healthyvs.osp+ost

100% 90.1% 94.5% 100%

C1+C2vs.C3

Healthy+ospvs.ost

95% 98.9% 90.5% 99.4%

MCW

Manualannotation

3mm Abnormavs.normal*

100% 67.5% 82.9% 100%

11(femoralneck)

77(femoralneck)

110(femoralneck)

KI

Visual C1vs.C2+C3

Healthyvs.osp+ost

100% 63.6% 68.8% 100%

C1+C2vs.C3

Healthy+ospvs.ost

100% 94.7% 52.4% 100%

80

MCW

Manualannotation

3mm Abnormalvs.normal*

100% 47.3% 60.3% 100%

Kathirveluetal.(2014)

64W 36 28 52.5±12.7

MCW Manualannotation

unclear Healthy+ospvs.ost

0.856(0.05,0.759-0.953)

Papamanthosetal.(2014)

315w

106 103 106 59.64±8.19


Osteopenic</=3.69

Healthyvsosteopenic

66.99 62.26 0.656

Osteoporotic</=3.24

Healthyvsosteoporotic

80.19 81.13 0.872

Osteoporotic</=3.24

Osteopenicvsosteoporotic

80.19 72.82 0.809

Anburajan(2014)

141W 21(spine)/20(femoralneck)

120(spine)/121(femoralneck)

49.07±3.06

MCW Computer-aidedsystem

unclear Healthyvs.ost

0.886(0.03,0.840-0.941)

Nagietal.(2014)

120w 60 0 60 60.17±5.5


3.35

Healthyvsosteoporotic

55 93.3 0.778(0.693–0.849)

81

Kimetal.(2014)

194W Unclear

Unclean

Unclear

65.6±8.6

MCW

Computer-aidedsystem

1.5mm

Healthy+ospvs.ost

14.3 96.2 0.737

2mm 35.7 91.8 2,22mm

67.9 78.5

2.5mm

67.9 69.6

3mm

85.7 43.7

3.5mm 67.9 78.5

Tab.4Papersincludedinthereview(2014-2018)

3.2 PERIODONTITISANDOSTEOPOROSISDespitetheinvestigationontherelationshipbetweentheincidenceofperiodontitisin

osteoporoticpatientshasbeenconsideredasecondaryoutcome,anarrativereviewhas

beencarriedouttosummarizethecontroversialavailableliteratureaboutthecorrelation

andtobetterunderstandthepositionoftheinternationalscientificcommunity.

The question addressed was the following: “Is periodontitis correlated with

osteoporosis?” and the applied research strategy included terms related to the

populationandtheinterventioninvestigatedandhasbeenperformedintwodatabases,

MEDLINEviaOVIDandEMBASE,updatein2018.

No language restrictions have been applied. The search strategy for MEDLINE and

EMBASE have used a combination of MeSH terms and text words which have been

combinedasPopulationANDIntervention.Tab.5

MEDLINEviaOVID/EMBASE MeSHterms Freetext LimitsPopulation

Bonedisease,metabolic/orexpbonedemineralization,pathologic/orexposteoporosis

Osteoporo$ORosteopeni$OR(bonelossadj2agerelated)

NOT(animalsNOThumans)

Intervention/Exposure ExpPeriodontalDiseases/

Periodont$orparodontos$orpyorrheaorfurcation

Tab.5Searchstrategy

Thestudiesassessingthecorrelationbetweenperiodontitisandosteoporosishavebeen

considered.Onlystudieswithatleastfivepatientswereselectedtoexcludeindividual

casereports.Studiescarriedoutascase-controlorcohortorcross-sectionalhavebeen

included.Studieshavebeenincludediftheydirectlycomparedtheassociationbetween

osteoporosisandchronicperiodontitis,measured intermsofclinicalattachment level

83

(CAL)and/orpocketprobingdepth(PPD).Theconsidereddiagnosisofosteoporosishas

beentheDXAtestateitherhiporspine.

Articlespublishedfrom1949to2018havebeenconsidered.Interestingly,thenumberof

articlesrelatedtothistopichasprogressivelyincreasedinthepastyears.Fig.21

Fig.21Numberofarticleperyearfrom1949to2018

Athree-stagescreening(titles,abstract,full-text)wasappliedtoincreasetheprecision

ofthereview.Atthestageoffulltextscreening,adataextractionformwascompleted

tochecktheeligibilityofthestudiesandtocollectdetailedinformationaboutpopulation,

interventionandoutcomes.Tab.6

Fifteenstudieshavematchedwiththeinclusioncriteriafortheliteraryreview.

Pilgrametal.havefoundaweakpositivecorrelationbetweentheperiodontalstatusand

BMD in longitudinal follow-up of 3 years though no correlation could be seen at

cross-sectionallevelin135participants(168).Brennanhasfoundasignificantcorrelation

betweenCALandBMDoftotalforearm,worstsiteT-score,anteroposteriorspine,and

whole body (119) while Tejal has reported a weak correlation between the CAL and

systemicosteoporosis(r=0.10–0.17),whichhasnotreachedastatisticalsignificance.

AlthoughWeyanthasfoundnostatisticallysignificantassociationbetweenperiodontal

indicators and BMD in 292 participants, a trend toward a more severe periodontal

diseasewasseeninalltheirmeasurementswithdecreasingBMD,indicationofapossible

0

20

40

60

801949

1963

1968

1972

1976

1980

1985

1989

1993

1997

2001

2005

2009

2013

2017

Num

bero

farticles

Years

84

association (117).Moeintaghavi andMarjanovic also have not found any statistically

significantassociationbetweenosteoporosisandperiodontitis,butthesamplesizehas

beenverysmall(169,170)

Ten out of 15 studies included have reported a significant association between

periodontitis and osteoporosis. Most of the included studies have been either cross

sectionalorprospectivestudiesandincludedpost-menopausalwomen.Themajorityof

the studies have reported values of CAL and have used the correlation or regression

coefficientsoroddratios.

Inconclusion,theliteraturepointsoutthatcouldbeacorrelationbetweenoralboneloss

and skeletal osteoporosis but the topic is still controversial. Several studieshave also

reported a correlation between systemic osteoporosis and number ofmissing teeth,

reducedalveolarcrestalheight,ortoothmobility.Whentoothlossoccurs,thereisno

mechanical stress in its antagonistic and in the alveolar bone supporting. The

consequenceistheexpansionofthebonemarrowcavitytogetherwitha loss inbone

volume.

Forallthesereasons,theassociationbetweenthesetwodiseasesisbiologicallyplausible

andseveralmechanismshavebeenproposedtolinkthem.Itcanbespeculatedthatthe

reducedBMDassociatedwithosteoporosismightalsoaffect the jawbonesandmight

acceleratealveolarbonelossfollowinginsultbyperiodontalbacteria(118).

Author(year)TotalN.pts

Age(y±SD))

Periodontaldiseasecut-off

BoneMineralDensity

Numberofpatientswithosteoporosis

Numberofpatientswithperiodontitis

AssociationbetweenCAL

andosteoporosis

Brennanetal.(2007)

1329 66.6±7.0 CALDEXAspine,hip,forearm,wholebody

Normal508(44.8%)Osteopenia469(41.4%)Osteoporosis157

yes

Passosetal.(2013)

521 60.8PPD>5mmCAL>6mm

DEXAproximalFemurandlumbarspine

Osteoporosis380Osteopenia141

94 yes

Habashnehetal.(2010)

400 62.5±6.4PPD,CAL5

mmPD/6mmCAL

DEXAlumbarspine(L1-L4)andfemoralneck

Normal94(23.5%)Osteopenia170(42.5%)

yes

85

Osteoporosis136(34.0%)

Iwasakietal.(2013)

39768.2

(60-80)

CAL,PPD≥4mm

DEXAlumbarspine(L2-L4),felneck

Normal161(44.8%)Osteopenia136(41.4%)Osteoporosis100

142(35.8%)

Yes

Marjanovicetal.(2013)

380 45-65PPD>5.5mmCAL>7mm


Osteoporotic98Nonosteoporotic282

150 No

Weyantetal.(1999)

29275.5±4.38

PPD,CALDEXAproximalFemurandlumbarspine

142 No

Gondim(2013)

148 58.93±4.7

CAL,PPDModerate:CAL≤5mmSevere:CAL>5mm

DEXAlumbarspine(L1-L4),femoralneck,andtotalfemur

Yes

Gomes-Filhoetal.(2007)

139 58.8±6.4

PPD>4mmCAL>3mm

DEXAfemur/spine

40cases60controls

48 Yes

Pilgrametal.(2002)

135 59PPDCAL


No

Penonietal.(2015)

13469.84

PPD>5mmCAL>6mm

DEXAproximalFemur,totalfemurandlumbarspine

Normal48Osteoporosis86 51 Yes

Julurietal.(2015)

100 60.12 CALPPD

DEXAlumbarspine

50cases50controls

Yes

Singhetal.(2014)

78 PPD,CALDEXAlumbarspine(L1-L4)

Normal22Osteopenia25Osteoporosis31

Yes

Tejaletal.(2000)

70 62.10±7.1 CAL,ABLDEXAproximalFemurandlumbarspine

No

Moeintaghavietal.(2013)

60 53.05 PPD,CALDEXAproximalFemurandlumbarspine

Normal20Osteopenia20Osteoporosis20

No

Grocholewiczetal.(2012)

37 59.4±5.6

PDIof6indicatesanattachmentlossof≥6mm

DEXAlumbarspine(L2-L4),femoralneck,anddistalradius

Yes

Tab.6Papersincludedinthereview

86

4 CLINICALSTUDYDESIGN

87

Inthepastyears,specificquantitativeandqualitativeindices/parameters,whichcanbe

calculated on dental panoramic radiographs, have been proposed as tools to detect

osteoporosis,withdifferentlevelsofaccuracy.

Amongst thequantitative indices, themostadoptedonesare themandibular cortical

width(MCW)andthepanoramicmandibularindex(PMI).

Regardingthequalitativeindices,theKlemettiindex(KI)isbyfarthemostappliedone.

A recent systematic review andmeta-analysis fromour group (165) showed that the

presence of any kind of cortical porosity (C2+C3) is associatedwith a sensitivity and

specificityindetectingosteoporosisof80.6%and64.3%,respectively.Theadvantageof

usingthisindex,comparedtoothersavailable,isthatitisstraightforwardandrelatively

easytomeasureanditdoesnotrequirespecificsoftwares.

ItisclearthatthepanoramicindicescannotreplacethediagnosisofosteoporosisbyBMD

measurementwithDXAscan.However,wheneverapanoramicradiographisavailable,

they might be opportunistically used to detect previously undiagnosed osteoporotic

patientsandreferthemtoaspecialist.

Whileseveralstudiessupporttheuseofpanoramicindices,theyhaveneverbeentested

inanItalianUniversityHospitalsettingandinastudyadequatelypoweredandcontrolled

forconfoundingvariablesandthereforeabletoputtogethertheinformationoftheKI

withDXA.

4.1 OVERALLSTUDYPLAN

Thisiscross-sectionalobservationalstudyaimingtorecruitacohortof124consecutive

post-menopausalwomen.Theonlystudyvisittookplaceatthe“CentroUniversitariodi

Odontoiatria,DipartimentodiMedicinaeChirurgia,UniversitàdiParma”.

All post-menopausal women ≥ 65 years old attending the Centro Universitario di

Odontoiatriainthenewpatients’orfollow-ups’clinicswereapproachedtocheckforthe

inclusion/exclusioncriteriaandtheirwillingnesstotakepartinthestudy.Furthermore,

doctors (general practitioners or osteoporosis specialists)were contacted andwill be

kindlyaskedtoinformtheirpatientthathaddoneaDXAscanwithinthepast12months

88

aboutthestudy.Potentiallyeligiblepatientswerebookedanappointmentatthe“Centro

UniversitariodiOdontoiatria,DipartimentodiMedicinaeChirurgia,UniversitàdiParma”

tocheckforinclusion/exclusioncriteriaandfortherecruitment.Aspartofthestudy,they

receivedafull-mouthexaminationofthehardandsofttissuesandanOPGatnocost.

Beforeenrolment,writtenandverbalinformationwasgiventothepatientsandwritten

informedconsentwasobtained.

4.2 INCLUSIONCRITERIAEachparticipanthadtomeetthefollowinginclusioncriteriatobeenrolledinthestudy:

• ≥65yearsold

• Inself-reportedmenopause,definedasthepermanentcessationofovulation,for

atleastoneyearbeforethevisit(171).

• ADXAexaminationatthehipandlumbarspineperformedwithintheprevious12

months

4.3 EXCLUSIONCRITERIAParticipantswerenoteligibleforparticipationinthestudyif:

• Affectedbysystemicdiseases(withtheexceptionofosteoporosis)recognizedto

severely affect bonemetabolism (e.g. Cushing's syndrome, Addison's disease,

diabetes mellitus type 1, leukaemia, pernicious anaemia, malabsorption

syndromes,chronicliverdisease,rheumatoidarthritis).

• KnowinglyaffectedbyHIVorviralhepatitis.

• Historyoflocalradiationtherapyinthelastfiveyears.

• Affectedbylimitedmentalcapacityorlanguageskillssuchthatstudyinformation

cannot be understood, informed consent cannot be obtained, or simple

instructionscannotbefollowed.

89

• Other severe acute or chronic medical or psychiatric condition or laboratory

abnormalitywhichmayincreasetheriskassociatedwithtrialparticipationormay

interferewith the interpretation of study results and, in the judgment of the

investigator,wouldmaketheparticipantinappropriateforentryintothistrial.

4.4 STUDYVISITSOnly1studyvisitwasperformedwithdatacollection:

• Signingofinformedconsent;

• Recordingofanyconcomitantmedication;

• Confirmation of participant eligibility in relation to the inclusion/exclusion

criteria;

• Examinationofhardandsofttissues;

• Full-mouth six-points periodontal chart, with recording of probing pocket

depth(PPD),recession(REC),furcationinvolvementandmobility.

• Dental panoramic radiograph (OPG) if not performed at the Centro

UniversitariodiOdontoiatriawithintheprevious12months

4.5 STUDYMEASUREMENTS4.5.1 Dentalpanoramicradiographs

If not performed within the previous 12 months at the Centro Universitario di

Odontoiatria,anOPGwasperformedduringenrolmentvisit.

OPGsareroutine low-dosex-raysthatareperformedduringdentalcheck-ups,follow-

upsorbeforedentaltreatments(e.g.extractions,implantplacement,etc.),astheyallow

the evaluation of bone and dental structures of both jaws, the sinus and temporo-

90

mandibular joints. Theyare routinelydone toeachnewpatient attending theCentro

UniversitariodiOdontoiatria.

AnORTHOPHOSXG3D(SironaDental)machinewillbeusedandthestandardsettings

recommendedbythedeveloperwillbeapplied.

Two examiners blinded to the DXA results (provided by the patients) independently

measured the panoramic indices on the OPGs. In particular, for the KI, the level of

mandibular cortical erosion in themental foramen regionwasqualitatively evaluated

afterzoomingtheOPGandoptimizationoftheimagecontrastandwhitebalance.

TheMCWandPMIweremeasuredwiththedigitalsoftwareprovidedbyORTHOPHOSXG

3D.

Afteratleast1week,theexaminerswillrepeatthemeasurementsin20%oftheOPGs,

inordertoevaluateintra-examinerreproducibility.

4.5.2 PeriodontalExaminationsA complete medical and dental history were obtained during enrolment visit. The

histories included demographic background information, systemic and dental status

information.

During the enrolment visit, a detailed examination of the hard and soft tissues was

performed and a trained examiner also registered the probing pocket depth (PPD),

gingivalrecession(REC),atsixsites(mid-buccal,buccal,disto-buccal,lingual,mid-lingual

anddisto-lingual)aroundeachtoothwithaUNC-15probe.Furcationinvolvementwas

assessedwithaNabersprobeandmobilitywasassessedwiththehelpofamirror.

Theresultsofthedentalandperiodontalexaminationwereexplainedtothepatients.

Itisimportanttohighlightthattheperiodontalanddentalexaminationwereperformed

aspartofthestandardexaminationthateachpatientreceiveswhenattendingtheCentro

UniversitariodiOdontoiatriaoranyotherdentalcentre.

91

4.6 STATISTICALPROCEDURES4.6.1 SamplesizeestimationThesamplesizewasbasedontheresultsofsensitivityandspecificityoftheKI(primary

outcome)obtainedfromasystematicreviewandmeta-analysisrecentlypublishedbyour

group(Calciolarietal.2015)andonthelevelofsensitivityofapanoramicindexthatboth

osteoporosisexpertsandpatientswouldconsiderasmeaningful.Infact,duringaPatient

andPublicInvolvement(PPI)group,boththepatientsandtheconsultantsinterviewed

agreedthatatestthatcorrectlyscreenforosteoporosisin80%ofthecaseswouldbe

worth, provided that the lower confidence limit is at least 55%. By taking into

considerationthesetargetvalues,andspeculatingaprevalenceofosteoporosisof30%

amongstpost-menopausalwomenattendingadentalhospital,124participantsneeded

toberecruitedforthisstudy.

4.6.2 StatisticalmethodThefollowingdatawererecorded:

- Sensitivity, specificity, false positive rate, negative positive rate of Klemetti Index

(primaryoutcome)indetectingosteoporosis.Thepresenceofahighlevelofmandibular

corticalerosion(C3)wereconsideredasasignofosteoporosis,whileasharpandeven

endostealmargin(C1,C2)wasconsideredasignofnormalbonemineraldensity.

- Sensitivity, specificity, false positive rate, negative positive rate and ROC curve of

MandibularCorticalWidthandPanoramicMandibularIndexindetectingosteoporosis

-Statisticalsignificantcorrelationbetweenperiodontalstatusandreducedsystemicbone

density(Periodontalprobingdepth(PPD),FullMouthBleedingScore(FMBS),FullMouth

Plaque Score (FMPS), Clinical attachment loss (CAL), Recession (REC), tooth mobility

(MOB),furcationinvolvement(FURC),toothloss).

SPSSsoftwarepackagehasbeenused.

92

5 RESULTS

93

5.1 GENERALANDDEMOGRAPHICDATAAtthemomentofthedrawingupofthisthesis,patient’senrolmentisstillinprogress.

70patientshavebeenenrolledtotakeparttotheclinicalstudy.All thepatientshave

satisfiedinclusioncriteria:

• ≥65yearsoldfemale

• Inself-reportedmenopause

• With a DXA examination at the hip and lumbar spine performed within the

previous12months

During the study visit, age, ethnicity, smoke habits, body mass index, height and

medicationshavebeenrecordedintheClinicalReportForm(CRF).Tab.16

5.2 OPGINDICESANDOSTEOPOROSISDATA

DxascanresultshavebeenregisteredintheClinicalReportForm(CRF)andpatientshave

beenclassifiedinhealthy,osteopenicandosteoporoticaccordingtotheT-scoreofeither

lumbarspineorfemurneck.Theworstvaluehasbeenusedtoclassifythebonedensity

status.Tab.17

Thedistributionofthet-scorevaluesbetweenthesamplehasbeen:

- Healthypatients: 2 (3%)

- Osteopenicpatients: 31 (44,2%)

- Osteoporoticpatients: 37 (52,8)

Accordingtotheliterature,patientshavebeenclassifiedintotwomaingroups:

- healthy+osteopenic(0): 33 (47%)

94

- Osteoporoticpatients(1): 37 (53%)

OPGshavebeenanalysedtoobtainmorphometricindicesvaluessuchasKlemettiindex

(KI),MandibularCorticalWidth(MCW),Mentalindex(MI),Panoramicmandibularindex

(PMI),Antegonialindex(AI),Gonialindex(GI)andMandibularratio(M/M).Tab.18

AllthepatientshavebeenanalysedfortheKlemettiindexandthedistributionbetween

thesamplehasbeen:

- C1: 13 (18%)

- C2: 28 (40,5%)

- C3: 29 (41,5%)

Accordingtotheliterature,KIhasbeenclassifiedintotwomaingroups:

- C1+C2(consideredhealthy): 46 (58,5%)

- C3(consideredosteoporotic): 29 (41,5%)

SincetheKlemetticlusterscanbeusedtoquantitativelyclassifyhealthy,osteopenicand

osteoporoticpatients, sensitivity and specificityhavebeencalculated considering�the

KlemettiindexasatoolforpredictionofreducedBMD(T-score</=-2,5).Thepresenceof

corticalerosion(C3vs.C1-C2)hasproducedasensitivityof61,1%andaspecificityof

79,4%withapositivepredictivevalueof75,9%andanegativepredictivevalueof65,9

%.�

�

�

�

�

�

95

KI

Truepositive(TP) 22

Truenegative(TN) 27

Falsepositive(FP) 7

Falsenegative(FN) 14

Sensitivity 61,1%

Specificity 79,4%

Positivepredictivevalue 75,9%

Negativepredictivevalue 65,9%

Tab.7Klemettiindexaccuracy

Mandibular corticalwidth (MCW) indexhasbeenanalysedon51patientsbecauseof

some technical issues in detecting the required measurements with accuracy in the

remaining19patients.ThecutoffvaluehasbeenchosenafterdrawingtheROCcurvein

ordertofindthehighestsensitivity/specificityandithasbeensetat3,33mm.Thelevels

of sensitivity and specificity associatedwith this index have been 72,2% and 64,7%

respectively.Tab.8-Tab.9-Fig.22

MCW

Area StandarderrorAsintotic

significance

AsintoticConfidenceInterval95%

Inferiorlimit Upperlimit

0,676 0,081 0,038 0,517 0,836

Tab.8MCWROC-areaunderthecurvedata

MCW

Sensitivity 72,2%

Specificity 64,7%

Tab.9Mandibularcorticalwidthindexaccuracy

96

A correlation between Klemetti Index and Mandibular Cortical Width has been

investigatedforthegroupof51patients.AMann-Whitneytesthasbeenappliedonthe

resultsobtainedbythesamepopulationandastatisticalsignificativecorrelationbetween

MCWandtheKlemettiC1+C2vs.C3hasbeenfound(p=0,001).

Accordingtothisfinding,theKIvalueforhealthypatientshasbeencorrelatedtopatients

withaMCWhigherthanthecut-offvalueasacombinedtooltopredictosteoporosis.

After this analysis, sensitivity and specificity have been calculated for the combined

indicesandtheresulthasbeen88,8%and58,8%respectively,withanegativepredictive

valueof90,9%.Tab.10

ROCCURVE

1-Specificity

Sensitivity

Fig.22MandibularcorticalwidthROCcurve

97

MCW/KI

Sensitivity 88,8%

Specificity 58,8%

Negativepredictivevalue 90,9%

Tab.10AccuracyofKIinassociationwithMCWwhenrelatedtot-scores

Any other combination of MCW and KI (KI=C3 and/or MCW<3,33 mm) have been

statisticallytestedbutnoimprovementinsensibility,specificityorpredictivevalueshave

beenobserved.

PanoramicMandibularIndex(PMI),Mentalratio(M/M),antegonialindex(AI)andgonial

index(GI),havebeenalsotestedaspredictortoolsindetectingosteoporosis.AROCcurve

hasbeendrawnandtheareaunderthecurvehasbeenidentified.Lowlevelofsensitivity

andspecificityhavebeenreportedforalltheseindices.Tab.11-Fig.23

ROCCURVE

1-Specificity

Sensitivity

Fig.23PMI,M/M,AI,GIROCcurve

98

SECONDARYINDICES

index Area StandarderrorAsintotic

significance

AsintoticConfidenceInterval95%

Inferiorlimit Upperlimit

PMI 0,552 0,088 0,538 0,380 0,725

M/M 0,456 0,085 0,604 0,290 0,622

AI 0,444 0,087 0,513 0,273 0,616

GI 0,512 0,085 0,885 0,346 0,678

Tab.11Accuracyofpanoramicmandibularindex,Mentalratio,antegonialindexandgonialindex

5.3 PERIODONTALDATAPeriodontaldata suchasPeriodontalprobingdepth (PPD), FullMouthBleedingScore

(FMBS),FullMouthPlaqueScore(FMPS),Clinicalattachmentloss(CAL),Recession(REC),

toothmobility(MOB),furcationinvolvement(FURC)havebeenregisteredinacomplete

periodontalchart(Tab.19).Bothcompleteedentulouspatientsordentatepatientshave

beenenrolledforthestudyandthenumberandpercentageofmissingteethhavebeen

takenintoaccount.Accordingtotheliterature,onlypatientswithatleast8teethhave

beenconsidereddentatepatientsandincludedinperiodontaldataanalysis.Fifty-eight

dentatepatientshavebeenclassifiedaccordingtot-scorecut-off.Thedistributionwithin

the sample has been 24 patients for the healthy group and 34 patients for the

osteoporoticgroup.Astatisticalsignificancehasbeeninvestigatedbetweenperiodontal

indicesanddiagnosisofosteoporosisaccordingtotheT-score(0=healthy/osteopenic;

1=osteoporotic).AKolmogorov-Smirnovtesthasbeenperformedtoassessthenormality

ofthedistributionoftheperiodontaldatasamples.TheK-Stesthasidentifiedtheclinical

attachmentlevelasanormaldistributionvariable.Inthiscaseat-testhasbeenapplied

to investigate the statistically significant correlation in case of normal distribution

99

(averageandstandarddeviation).IncaseofPPD,REC,MOBandFURCaMann-Whitney

testhasbeenusedtotestthecorrelation(medianandquartile).

Periodontalprobingdepth (PPD):58patientshavebeenconsidered for the statistical

analysis. A six-sites periodontal probing has been performed on each tooth and the

probingdepthhasbeenclassifiedintwoclustersaccordingtoacut-offof5mm.

Sincethepocketprobingdepthhasbeendefinedasanon-normaldistributedvariable

(Kolmogorov-Smirnovtest),medianand25%quartilehavebeencalculated.Astatistically

significant correlation between PPD and BMD has been found for the patients with

PPD>/=5mm(p=0,006).ThemedianofthepatientwithPPD>/=5mmgrouphasbeen

9,75%(25quartile:2,7%)inthehealthygroup,and3,45%(25quartile:0,6%).Tab.12

Sample N Median(%) 25quartile(%)

Healthy 24 9,75 2,7

Osteoporotic 34 3,45 0,6

Tab.12Pocketprobingdepth(PPD)statisticalanalysis:medianand1stquartile

TheaforementionedcorrelationhasbeentestedbetweenPPDandBMD,consideredas

adichotomicvaluedefinedonthet-scorecut-offs.Thecorrelationhasbeenalsotested

considering t-score as a continuous variable and a Spearman’s rank correlation

coefficient has been applied. Spearman’s rho has shown a statistical significance

(p=0,005).Fig.24

100

Fig.24ScatterplotrepresentingthedistributionofthesiteswithaPPD³5mminrespectoft-scoresasacontinuous

variable

Clinicalattachmentloss(CAL):ClinicalattachmentlosshasbeendefinedastheRECin

additiontoPPDvalues.Averageandstandarddeviationhavebeencalculatedandt-test

hasbeenperformedtodemonstrateacorrelationbetweenCALandt-scores.Siteshave

beenclassifiedinthreeclusters,withCALof1-2mm,CALof3-4mmandCAL>5mm.

Onlytheclusterof3-4mmofCALhasshownastatisticallysignificantcorrelationwitht-

scoresclassification(healthyandosteoporotic)withap=0,21.Theaverageofsiteswith

CALof3-4mmhasbeen49,4%(SD11,05%)forthehealthygroupand56,9%(SD12,6

%)fortheosteoporoticgroup.Tab.13

%ofsite

swith

PPD³5

mm

t-score

101

Sample N CALgroups Average(%)Standard

deviation(%)

Healthy 24

%siteswithCAL1-2mm 22,429 14,8368


%siteswithCAL>5mm 28,563 20,2506

Osteoporotic 34



%siteswithCAL>5mm 20,388 15,1708

Tab.13Clinicalattachmentloss(CAL)statisticalanalysis:averageandstandarddeviation

TheSpearman’srankcorrelationcoefficienthasbeenalsoappliedtotheCALinorderto

investigate the correlation between attachment level and t-score as a continuous

variable.Similarlytothet-test,Spearman’srhohasidentifiedacorrelationtothegroup

withCALof3-4mm(p=0,13).Fig.25

Fig.25ScatterplotrepresentingthedistributionofthesiteswithaAL3-4mminrespectoft-scoresasacontinuous

variable

%ofsite

swith

AL3-4mm

t-score

102

Toothloss:Thenumberofteethlosshasbeenanalysedonthewholesample.AMann-

Whitneytestforthenon-parametricvariableshasbeenappliedtoinvestigateastatistical

significanceinrelationtothet-score(dichotomicvalue)andapvalueof0,007hasbeen

found.Themedianofthepercentageofteethloss(considered28teethas100%)has

been25%(25quartileof17,8%)forhealthygroup(33patients),and14,3%(25quartile

of7,1%)fortheosteoporoticgroup(37patients).Tab.14

The Spearman’s rank correlation coefficient has been also applied and no statistical

differenceshavebeendemonstratedconsideringt-scoreasacontinuousvariable

Sample N Median(%) 25quartile(%)

Healthy 33 25 17,8

Osteoporotic 37 14,3 7,1

Tab.14Toothlossstatisticalanalysis:medianand1stquartile

Recession, Furcation, Mobility: All the remaining periodontal indices that have been

statistically tested, have shown no significance between groups. For the furcation

involvement, the frequency has been analysed but the chi-square test has shownno

significance.Tab.15

Indices Median(%) 25quartile(%)

REC>3mm(%sites) 0,25 0

REC≤3mm(%sites) 99,4 95,35

Mobility(%teeth) 6,3 0

Tab.15Recession(REC)andtoothmobility:medianand1stquartile

103

PatientsIDAGE ETHNICITY SMOKE HEIGHT WEIGHT BMI Vit.D BISPHOSPHONATES

(0=no;1=yes)

L-Z001 73 caucasian 0 154,5 49 20,53 1 1

G-P002 72 caucasian 0 165 101 37,1 0 0

M-M003 79 caucasian 1 158,1 50 20 0 1

A-B004 73 caucasian 1 162,5 65 24,62 0 0

R-L005 81 caucasian 0 161 56 21,6 0 0

C-G006 79 caucasian 0 158 74 29,64 1 0

L-M007 68 caucasian 0 154 59 24,88 0 0

T-C008 67 caucasian 1 157,4 59 23,81 0 0

M-G009 68 caucasian 0 165 83 30,49 0 0

S-M010 76 caucasian 0 157 61 24,75 0 0

O-C011 73 caucasian 0 160,4 49 19,05 1 0

M-P012 73 caucasian 0 156,3 53 21,69 0 0

O-C013 74 caucasian 0 160 59 23,05 1 0

T-C014 70 caucasian 0 160,2 60 23,38 0 0

L-B015 67 caucasian 0 156 61 25,07 0 0

G-M016 77 caucasian 0 153 56 23,92 1 0(2y)

N-G017 81 caucasian 0 144,4 57 27,34 0 0

A-B018 66 caucasian 1 153,6 55 23,31 1 0

G-P019 73 caucasian 0 164 56 20,82 0 0

R-G020 80 caucasian 0 167 66 23,67 1 0

D-N021 69 caucasian 0 153,2 48 20,45 0 0

A-C022 72 caucasian 1 154,5 54 22,62 0 0

M-M023 67 caucasian 0 153 62 26,49 0 0

M-S024 69 caucasian 0 154,8 55 22,95 1 0

S-G025 72 caucasian 0 151,2 66 28,87 0 0

L-T026 71 caucasian 1 155,2 50 20,76 1 0

M-C027 74 caucasian 1 162,7 57 21,53 0 0

E-S028 76 caucasian 0 160 46 17,97 1 0

M-G029 79 caucasian 0 152 54 23,37 0 0

A-C030 67 caucasian 1 154 53 22,35 0 0

M-F031 65 caucasian 162 75 28,6 1 0(3m)

104

M-M032 65 caucasian 0 166 51 18,5 1 0

M-P033 67 caucasian 0 148 53 24,2 1 0(7y)

MR-B034 65 caucasian 0 162 60 23 0 0

G-C035 65 caucasian 0 161 57 22 1 0

A-G036 66 caucasian 0 164 58 21,6 1 0(5y)

G-S037 66 caucasian 0 159 56 22,2 0 0

R-S038 66 caucasian 0 158 89 35,9 1 1

G-S039 66 caucasian 0 155 47 19,7 0 0

G-C040 66 caucasian 0 146 60 27,9 1 1

MN-T041 67 caucasian 0 160 69 27 1 0

F-D042 66 caucasian 1 152,7 54 23,16 0 0

M-A043 75 caucasian 0 154,7 55 22,98 0 0

MP-G044 84 caucasian 0 159,5 66 25,94 0 0

A-D045 67 caucasian 0 148 72 32,9 1 0

R-C046 65 caucasian 1 156 55 22,6 1 0

L-R047 65 caucasian 0 163 60 22,6 1 0

D-B048 67 caucasian 0 158 54 21,6 1 0

C-P049 67 caucasian 0 153 66 28,2 1 1

A-P050 78 caucasian 0 160,3 63 24,52 0 0

M-B051 74 caucasian 0 160,5 64 24,84 0 0

M-M052 66 caucasian 0 167 103 36,9 1 0

PKS053 60 caucasian 0 149,5 57,2 1 1

AMF054 63 caucasian 0 152,3 65 1 0(6m)

K-D055 63 caucasian 0 157,6 56 1 0

C-M056 66 caucasian 0 160 108 1 1

PFF057 59 caucasian 0 156 60 0 0

G-G058 75 caucasian 0 158,2 92 0 0

NMF059 66 caucasian 0 166 62 0 1

DJG060 69 caucasian 0 153 51 1 1

DIG061 72 caucasian 0 155 52 0 0

LMK062 60 caucasian 0 166 48,3 17,5 1 1

J-W063 55 caucasian 0 162 63 1 0

J-B064 68 caucasian 0 153 48,3 1 0

MBM065 61 caucasian 0 165 68 1 0(4y)

105

V-F066 63 caucasian 0 161,5 52,1 1 1

SAR067 53 caucasian 0 159 71 0 0

JAL068 60 caucasian 0 155 52 1 0(2y)

A-S069 60 caucasian 0 160 58 0 no

A-L070 70 caucasian 0 152 51,3 0 1

E-M071 66 caucasian 1 175 85 27,8 0 0

Tab.16Demographicdatacollection.Age,etnicity,smoke,height,weight,bmiandmedicationshavebeenrecorded

106

PatientsID DxascanT-score diagnosis classification

lumbarspine femurneck worstvalue

L-Z001 -1,9 -3,4 -3,4 Osteoporotic 1

G-P002 4,2 -0,2 -0,2 Healty 0

M-M003 -1,6 -1,8 -1,8 Osteopenic 0

A-B004 0,2 -2,4 -2,4 Osteopenic 0

R-L005 -2,4 -1,4 -2,4 Osteopenic 0

C-G006 -2,4 -2,2 -2,4 Osteopenic 0

L-M007 -1,2 -0,7 -1,2 Osteopenic 0

T-C008 -3,2 -3,2 -3,2 Osteoporotic 1

M-G009 -1,2 -1,1 -1,2 Osteopenic 0

S-M010 -3,1 -2,5 -3,1 Osteoporotic 1

O-C011 -1 -2,7 -2,7 Osteoporotic 1

M-P012 -1,3 -2,5 -2,5 Osteoporotic 1

O-C013 -3 -2,8 -3 Osteoporotic 1

T-C014 -2 -2 -2 Osteopenic 0

L-B015 -1,8 -1,5 -1,8 Osteopenic 0

G-M016 -1,2 -2,5 -2,5 Osteoporotic 1

N-G017 -2,7 -1,8 -2,7 Osteoporotic 1

A-B018 -2,6 -2 -2,6 Osteoporotic 1

G-P019 -3,2 -1,7 -3,2 Osteoporotic 1

R-G020 -1,2 -1,6 -1,6 Osteopenic 0

D-N021 -3,6 -2,2 -3,6 Osteoporotic 1

A-C022 -1,8 -1,6 -1,8 Osteopenic 0

M-M023 -1,4 -1 -1,4 Osteopenic 0

M-S024 -2,1 -2,1 -2,1 Osteopenic 0

S-G025 0,6 -1,3 -1,3 Osteopenic 0

L-T026 -2,1 -1,1 -2,1 Osteopenic 0

M-C027 -2,4 -1,3 -2,4 Osteopenic 0

E-S028 -2,7 -2,6 -2,7 Osteoporotic 1

M-G029 -2,2 -1,8 -2,2 Osteopenic 0

A-C030 0,8 -1,9 -1,9 Osteopenic 0

M-F031 -1,3 -1,3 Osteopenic 0

M-M032 -2,1 -2,4 -2,4 Osteopenic 0

M-P033 -3,3 -1,4 -3,3 Osteoporotic 1

107

MR-B034 -1,6 -1,7 -1,7 Osteopenic 0

G-C035 -2,8 -2,7 -2,8 Osteoporotic 1

A-G036 -3,6 -3,8 -3,8 Osteoporotic 1

G-S037 -1,9 -2,1 -2,1 Osteopenic 0

R-S038 -2,6 -1,5 -2,6 Osteoporotic 1

G-S039 -2 -1,4 -2 Osteopenic 0

G-C040 -3,3 -1,9 -3,3 Osteoporotic 1

MN-T041 -1,9 -1,9 Osteopenic 0

F-D042 -1,6 -1,8 -1,8 Osteopenic 0

M-A043 -2,1 -3 -3 Osteoporotic 1

MP-G044 -1,6 -2,2 -2,2 Osteopenic 0

A-D045 -1 -1,5 -1,5 Osteopenic 0

R-C046 -1,1 -2,1 -2,1 Osteopenic 0

L-R047 -1,9 -1,9 -1,9 Osteopenic 0

D-B048 -1,6 -0,9 -1,6 Osteopenic 0

C-P049 -2,2 -2 -2,2 Osteopenic 0

A-P050 0,1 -0,7 -0,7 Healty 0

M-B051 -1,9 -1,4 -1,9 Osteopenic 0

M-M052 -0,9 -1,6 -1,6 Osteopenic 0

PKS053 -2,5 -2,5 Osteoporotic 1

AMF054 -3,1 -3,1 Osteoporotic 1

K-D055 -2,7 -2,7 Osteoporotic 1

C-M056 -2,5 -2,5 Osteoporotic 1

PFF057 -3,3 -3,3 Osteoporotic 1

G-G058 -2,7 -2,7 Osteoporotic 1

NMF059 -3,7 -3,7 Osteoporotic 1

DJG060 -2,6 -2,6 Osteoporotic 1

DIG061 -3,8 -3,8 Osteoporotic 1

LMK062 -3,2 -3,2 Osteoporotic 1

J-W063 -2,5 -2,5 Osteoporotic 1

J-B064 -3,5 -3,5 Osteoporotic 1

MBM065 -2,5 -2,5 Osteoporotic 1

V-F066 -3,6 -3,6 Osteoporotic 1

SAR067 -2,7 -2,7 Osteoporotic 1

JAL068 -2,9 -2,9 Osteoporotic 1

108

A-S069 -3,6 -3,6 Osteoporotic 1

A-L070 -2,5 -2,5 Osteoporotic 1

Tab.17T-scoresanddiagnosticclassificationinhealty,osteopenicandosteoporotic.Healthyandosteopenicpatientshavebeenclassifiedas"0"andosteoporoticas"1".

109

Patients MorphometricIndices Diagnosis

KLEMETTI

INDEX

MCW

mm

PMI

mm

M/M

mm

AI

mm

GI

mm

0=healthy/osteopenic;

1=osteoporotic

L-Z001 C2 4,57 0,40 3,15 3,27 1,96 1

G-P002 C2 3,62 0,26 2,56 2,48 1,22 0

M-M003 C2 3,14 0,22 1,70 3,26 1,52 0

A-B004 C2 1,97 0,15 1,65 2,56 1,61 0

R-L005 C2 2,55 0,19 1,69 2,88 1,41 0

C-G006 C3 1,95 0,17 1,79 2,02 1,15 0

L-M007 C2 3,73 0,34 1,88 2,58 1,58 0

T-C008 C2 3,21 0,30 1,88 3,09 1,91 1

M-G009 C1 3,84 0,30 2,24 2,80 1,37 0

S-M010 C3 4,27 0,33 2,05 3,43 1,26 1

O-C011 C3 2,33 0,29 2,48 3,15 1,35 1

M-P012 C3 2,92 0,24 2,62 3,15 1,69 1

O-C013 C3 0,97 0,08 2,15 2,19 1,50 1

T-C014 C2 4,20 0,62 3,54 2,42 2,08 0

L-B015 C2 3,83 0,33 2,64 3,49 4,49 0

G-M016 C2 3,03 0,24 2,67 2,11 1,71 1

N-G017 C3 2,73 0,20 2,03 2,35 1,61 1

A-B018 C1 3,36 0,25 2,41 3,34 1,98 1

G-P019 C3 1,93 0,15 2,01 2,06 0,97 1

R-G020 C2 1,96 0,15 1,57 1,50 1,48 0

D-N021 C2 2,44 2,33 2,50 2,16 1,12 1

A-C022 C3 3,02 0,34 3,23 2,24 1,91 0

M-M023 C1 3,73 0,27 1,85 1,57 1,51 0

M-S024 C1 4,65 0,36 2,12 3,10 1,28 0

S-G025 C1 3,80 0,26 2,08 2,83 1,51 0

L-T026 C1 4,37 0,37 2,99 2,99 1,59 0

M-C027 C2 3,14 0,22 2,02 2,53 1,80 0

E-S028 C1 4,20 0,39 1,41 3,30 1,99 1

M-G029 C2 4,13 0,23 1,28 1,69 1,07 0

A-C030 C1 5,39 0,42 2,28 3,86 1,33 0

110

M-F031 C1 4,55 0,32 2,09 2,55 1,69 0

M-M032 C2 3,89 0,31 2,27 3,10 1,13 0

M-P033 C3 4,20 0,31 2,37 3,36 1,42 1

MR-B034 C1 4,34 0,31 1,90 3,31 1,80 0

G-C035 C3 1,23 0,10 1,81 1,99 0,84 1

A-G036 C2 3,32 0,26 1,86 2,39 1,41 1

G-S037 C2 3,78 0,35 2,23 2,73 1,00 0

R-S038 C2 3,28 0,34 2,44 3,00 1,45 1

G-S039 C2 5,02 0,40 1,95 4,72 2,94 0

G-C040 C3 2,33 0,17 1,95 3,42 2,01 1

MN-T041 C3 3,53 0,25 2,35 4,11 2,10 0

F-D042 C1 4,23 0,41 3,45 3,17 1,76 0

M-A043 C2 2,09 0,13 1,27 2,41 1,62 1

MP-G044 C3 3,39 0,20 1,46 1,99 0,84 0

A-D045 C2 3,48 0,21 1,89 2,51 1,28 0

R-C046 C2 3,12 0,20 1,99 1,53 1,14 0

L-R047 C3 2,67 0,20 1,94 2,76 1,47 0

D-B048 C2 4,19 0,31 2,06 2,93 2,01 0

C-P049 C2 3,43 0,31 2,18 1,61 1,85 0

A-P050 C3 3,31 0,21 1,21 2,60 1,75 0

M-B051 C3 2,13 0,16 2,34 2,17 1,47 0

M-M052 C2 2,06 0,18 2,75 3,15 75,37 0

PKS053 C2 n/d n/d n/d n/d n/d 1

AMF054 C3 n/d n/d n/d n/d n/d 1

K-D055 C3 n/d n/d n/d n/d n/d 1

C-M056 C2 n/d n/d n/d n/d n/d 1

PFF057 C3 n/d n/d n/d n/d n/d 1

G-G058 C3 n/d n/d n/d n/d n/d 1

NMF059 C3 n/d n/d n/d n/d n/d 1

DJG060 C3 n/d n/d n/d n/d n/d 1

DIG061 C3 n/d n/d n/d n/d n/d 1

LMK062 C3 n/d n/d n/d n/d n/d 1

J-W063 C1 n/d n/d n/d n/d n/d 1

111

J-B064 C3 n/d n/d n/d n/d n/d 1

MBM065 C3 n/d n/d n/d n/d n/d 1

V-F066 C3 n/d n/d n/d n/d n/d 1

SAR067 C2 n/d n/d n/d n/d n/d 1

JAL068 C1 n/d n/d n/d n/d n/d 1

A-S069 C3 n/d n/d n/d n/d n/d 1

A-L070 C2 n/d n/d n/d n/d n/d 1

Tab.18Panoramicmorphometricindices:Klemettiindex,mandibularcorticalwidth(MCW),panoramicmandibularindex(PMI),mentalratio(M/M),antegonialindex(AI),gonialindex(GI).

112

PatientNofteeth

loss

%teeth

loss

%teethwith

mobiiltyfurcations T-score

%siteswith

PPD≥5mm

%siteswith

PPD<5mm

%siteswith

REC>3mm

%siteswith

REC≤3mm

%siteswith

AL1-2mm

%siteswith

AL3-4mm

%siteswith

AL≥5mm

(28=100%)(no/gradeI=0;

gradeII/III=1)

(0=healthy/osteopenic

1=osteoporotic)

L-Z001 3 10,7 8 0 1 0 100 0 100 11,3 83,4 5,3

G-P002 7 25 62,5 0 0 13,9 86,1 0 100 15,9 54,9 29,2

M-M003 22 78,6 0 0 0 13,9 86,1 18 82 6 36,4 57,6

A-B004 28 100 0 0 0 0 100 0 100 16,7 83,3 0

R-L005 28 100 0 0 0 16,7 83,3 6 94 3 41 56

C-G006 28 100 0 0 0 33,3 66,7 0 100 36,7 30 33,3

L-M007 4 14 4 0 0 1,3 98,7 7,7 92,3 24,3 48,1 27,6

T-C008 26 92,8 0 0 1 0 100 83,3 16,7 0 0 100

M-G009 16 57,1 0 0 0 5,3 94,7 1,7 98,3 19,4 40,3 40,3

S-M010 6 21,4 56,5 1 1 5,8 94,2 14,5 85,5 3,6 25,4 71

O-C011 14 50 0 0 1 3,6 96,4 4,7 95,3 13,1 53,6 33,3

M-P012 3 10,7 23,1 0 1 7 93 1,9 98,1 31,4 50 18,6

O-C013 5 17,9 26,9 0 1 3,8 96,2 0 100 26,5 57,6 15,9

T-C014 28 100 0 0 0 0 0 0 0 0 0 0

L-B015 3 10,7 48 1 0 27,3 72,7 1,3 98,7 8,6 44,7 46,7

G-M016 3 10,7 46,1 1 1 12,8 87,2 0,6 99,4 20,5 47,4 32,1

N-G017 22 78,6 0 0 1 19,4 80,6 8,3 91,7 2,8 22,2 75

A-B018 1 3,6 0 0 1 0,6 99,4 0,6 99,4 25,6 63,5 10,9

113

G-P019 10 35,7 33,3 0 1 18,7 81,3 0 100 17,7 35,4 46,9

R-G020 21 75 0 0 0 8,3 91,7 0 100 10 78,3 11,7

D-N021 2 7,1 51,8 1 1 9,8 90,2 6,2 93,8 19,1 46,9 34

A-C022 6 21,4 0 0 0 6,7 93,3 0 100 29,3 63,3 7,4

M-M023 11 39,3 4,7 0 0 21,7 78,3 0 100 22,5 54,2 23,3

M-S024 5 17,9 17,2 0 0 5,7 94,3 1,1 98,9 25,3 53,4 21,3

S-G025 5 17,9 0 0 0 4,2 95,8 0 100 38,2 56,9 4,9

L-T026 3 10,7 20 1 0 15,3 84,7 0 100 4,6 50,7 44,7

M-C027 14 50 40,9 0 0 44,7 55,3 2,3 97,7 3 28 69

E-S028 12 42,8 0 0 1 0 100 4,2 95,8 22,9 42,7 34,4

M-G029 8 28,6 31,8 0 0 3 97 5,3 94,7 22,7 58,3 19

A-C030 17 60,7 50 0 0 52,6 47,4 0 100 2,6 26,9 70,5

M-F031 0 0 0 0 0 1,6 98,4 0 100 57,5 40,9 1,6

M-M032 6 21,4 10 0 0 0,5 99,5 0,5 99,5 57,8 37,2 5

M-P033 1 3,6 0 0 1 0,6 99,4 0 100 46,3 51,8 1,9

MR-B034 4 14,3 0 0 0 5,3 94,7 3,3 96,7 20 63,3 16,7

G-C035 18 64,3 50 0 1 6,7 93,3 3,3 96,7 16,7 70 13,3

A-G036 0 0 3,6 0 1 2,9 97,1 0 100 22,1 69,6 8,3

G-S037 5 17,9 18,5 1 0 22,2 77,8 0,6 99,4 17,9 58,6 23,5

R-S038 13 46,4 18,7 0 1 7,3 92,7 0 100 8,4 70,8 20,8

G-S039 13 46,4 0 0 0 2,6 97,4 0 100 20,2 71,9 7,9

G-C040 8 28,6 0 0 1 0 100 0 100 24,2 71,2 4,6

114

MN-T041 0 0 0 0 0 2,4 97,6 0 100 35,7 60,7 3,6

F-D042 4 14,3 34,6 0 0 16,7 83,3 0 100 12,3 50 37,7

M-A043 26 92,8 33,3 0 1 58,3 41,7 5,5 94,5 2,8 30,5 66,7

MP-G044 28 100 0 0 0 0 0 0 0 0 0 0

A-D045 3 10,7 4 1 0 6,7 93,3 0 100 20 73,3 6,7

R-C046 22 78,5 0 0 0 25 75 5 95 2 55 43

L-R047 6 25 41,6 1 0 30,5 69,5 0 100 18 38,1 43,8

D-B048 8 28,6 7,6 0 0 0,6 99,4 0 0 41,6 51,2 7,1

C-P049 6 21,4 76,9 1 0 12,8 87,2 7 93 16,6 42,9 50,5

A-P050 28 100 0 0 0 14 86 1,2 98,8 21,7 56,4 21,8

M-B051 5 17,8 55,5 0 0 14,8 85,2 1,8 98,2 12,3 47,5 40,2

M-M052 5 17,9 24 1 0 14,7 85,3 0,7 9,3 12 44 44

PKS053 1 3,6 0 1 1 27,5 72,5 1,5 98,5 8 49 43

AMF054 2 7,1 0 1 1 5,7 94,3 0 100 60,9 30,1 9

K-D055 1 3,6 0 0 1 5,2 94,8 0 100 32,8 60,3 6,9

C-M056 2 7,1 18,5 0 1 9,3 90,7 0 100 21 61,7 17,3

PFF057 4 14,3 60,7 0 1 4,2 95,8 0 100 27,4 56,5 16,1

G-G058 9 32,1 52,6 0 1 0,9 99,1 2,6 97,4 9,6 59,6 30,8

NMF059 8 28,6 30 0 1 8,3 91,7 0 100 12,5 64,2 23,3

DJG060 5 17,8 45,8 0 1 1,4 98,6 4,8 95,2 19,4 54,9 25,7

DIG061 9 32,1 21 0 1 1,7 98,3 0,9 99,1 25,5 59,6 14,9

LMK062 2 7,1 38,5 0 1 1,3 98,7 0 100 33,3 53,4 12,8

115

J-W063 2 7,1 17,2 0 1 0,6 99,4 0 100 35,6 59,8 4,6

J-B064 4 14,3 0 0 1 0 100 0 100 42 52 6

MBM065 6 21,4 54,5 1 1 5,5 94,5 4,5 95,5 18,2 52,3 29,5

V-F066 5 17,8 4 0 1 0 100 0 100 27,3 68,7 4

SAR067 1 3,6 0 0 1 2,7 97,3 0 100 51,6 43 5,4

JAL068 2 7,1 34,6 0 1 0 100 1,3 98,7 7 64,7 28,3

A-S069 4 14,3 3,6 1 1 2,4 97,6 0,6 99,4 2,4 66,7 30,9

A-L070 8 28,6 5 1 1 3,3 96,7 5 95 5 68,3 26,7

Tab.19Periodontaldatacollection:Number/percentageofteethloss,percentageofteethwithaugmentedmobility,furcationinvolvement,percentageofsiteswithpockedprobingdepth(PPD),recession(REC)andclinicalattachmentlevel(AL)

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6 DISCUSSION

117

Accordingtotherevisionoftheliteraturethatithasbeenperformed,fouroutofthefive

studiesincludedreportedasignificantcorrelationbetweenBMDmeasuredatdifferent

systemicskeletalsitesandmandibleBMD.Cakuretal(172)reportedin2009noevidence

ofanyrelationshipbetweensystemicandmandibularBMD.However,weneedtobevery

cautious on drawing conclusions, since these studies are not easily and satisfactory

comparable due to several confounding factors such as different techniques used to

measureBMDandthedifferentanatomicsitesconsidered.

Since the heterogeneity of the studies and considering that the meta-analysis was

performedtakingintoaccountonlytwo-studies,itispossibletostatethatthesignificance

ofthesedatacanbequestionable.

Forthesereasons,aclinicaltrialhasbeendesignedinordertoinvestigatethecorrelation

betweensystemicbonemineraldensity(BMD)andjawbonescondition,usingasetof

specific radiographic morphometric indices proposed in the last decades. Moreover,

since the enrolment has been performed in a Dental Hospital, it was decided to

investigate the relationship between BMD and periodontal status in this group of

selectedpatients.Thecorrelationbetweent-scoresandperiodontalindiceshasalready

beenproposedinscientificliteraturebut,similarlytothecorrelationbetweenBMDand

jawbonedensity,theevidenceispoorandcharacterizedbyalargeheterogeneityofthe

studies.TheavailableliteratureonapossiblecorrelationhasbeenreviewedinChapter

3.

6.1 PANORAMICMORPHOMETRICINDICESFORDETECTINGREDUCEDBMD

Severalclinicalstudiesinvestigatedtherelationshipbetweenbonedensitymeasuredin

differentsystemicskeletalsitesandinthejawbonesinsubjectswithdifferentTscores.

Althoughmanyofthesestudieshavefoundapositivecorrelation(132-139),othershave

reportedthatjawbonedensityisnot,oronlytoalimiteddegree,correlatedtothedensity

inothersystemicsites(140-142).Ithasalsobeendemonstratedthatthatthereareno

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differences in jawbonedensitybetweennormalandosteopenic/osteoporotic subjects

(143,144).

Theavailableliteratureontheaccuracyofpanoramicmorphometricindicesindetecting

reducedBMDhasbeensystematicallyreviewedinChapter3.Inthepast20yearsseveral

evidenceshavebeenpublishedon theaccuracyofqualitative/quantitativepanoramic

indices in screening for reduced skeletal density (either osteopenia or osteoporosis)

(173).Consideringthehighpercentageofpeopleattendingregulardentalvisitsandthe

fact thatpanoramic radiographsof the jawbonesarenowadaysacommonprocedure

duringroutinedentalcheck-upsorbeforeseveraldentaltreatments(174-176),itwould

be of great clinical value if dentists could opportunistically use panoramic X-rays to

identifypatientsathighriskofosteoporosisandatleastreferthemtometabolicbone

diseasesclinic.

Inthestudypresented,theKlemettiindex(KI),thequalitativeindex,hasbeenevaluated

onthewholesampleof70patients,whilepanoramicmorphometricquantitativeindices

such as mandibular cortical width (MCW), panoramic mandibular index (PMI),

mandibularratio(M/M),antegonialindex(AI)andgonialindex(GI)havebeenmeasured

on51patientsduetotechnicalradiologicalissues.

Inlinewithseveralresearchersinthefield,weagreethatthebasalareaofthemandible

posteriortothementalforamenisprobablytheonlypartofthejawswithreasonably

suitablecharacteristicstobeastandardsiteforBMDmeasurements,sinceithassmall

inter- and intra-individual variations in anatomical size, shape, bone structure and

function(177),althoughithastoberememberedthatthemandibularforamencannot

bedetectableinallconditions.

Mandibular cortical width represents the thickness of the mandibular cortex and is

usuallymeasuredinthementalforamenregion.Regardlessthelimitationsofthisstudy

duetothesamplesize,thestatisticalanalysishasshownasignificantcorrelationbetween

MCWandastatusofosteoporosisandacut-offvaluehasbeensetat3,3mmwitha

sensitivityandspecificityof72,2%and64,7%,respectively.Accordingtotheliterature,

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MCWhas showed a better specificity rather than sensitivity in detecting peoplewith

reducedBMD,since90%ofpeoplewithMCW≥4mmcouldbecorrectlyidentifiedas

havinganormalBMD(157).

Regarding the qualitative measurement, Klemetti index has been evaluated by two

differentblindedexaminersandcorrelatedtothestatusofbonehealthorosteoporosis

of the patient. KI qualitatively classifies themandibular cortex distally to themental

foramenin3categoriesaccordingtothepresenceoferosions.Thepresenceofcortical

erosion(C3vs.C1-C2)hasproducedasensitivityof61,1%andaspecificityof79,4%with

apositivepredictivevalueof75,9%andanegativepredictivevalueof65,9%. In the

revisionoftheliterature,thepresenceofanykindofcorticalerosion(C2+C3categories,

asassessedwithKI)hasseemedasensitive tool todetect reducedBMD,since itwas

associatedwithatleastosteopeniainapproximately80%ofthecases(160).

ExaminingtheclinicaltrialresultsofMCWandKI,apossiblecorrelationbetweenthetwo

mainindiceshasbeentestedandastrongcorrelationhasbeenfound(pvalue=0,001).

According to this finding,a correlationbetween the twocut-off values that identifya

healthypatient (MCW>3,3mmandKI=C1/C2)and t-scoreshasbeen investigated.The

correlationhasshownanincreaseinsensibilityandspecificitytillthevaluesof88,8%

and58,8%,respectively,but,mostimportant,demostratedanegativepredictivevalue

of91%.Theseindicescanbeconsideredpotentiallyusefultoscreenforreducedskeletal

BMDifusedincombinationandinparticulartoidentifyahealthypatientinmorethan

90%ofcases.

Even if scientific literature has demonstrated that panoramicmandibular index (PMI)

seem themost accurate and consistent quantitative tool to screen for reducedBMD

(sensitivity and specificity >70%) (161), this work PMI has reached no significance if

relatedtothet-scoresvaluestoscreenforhealthyorosteoporoticpatients. Mostofthe

studiesreportedacutoffvalueof0,3,withlevelsofsensitivityandspecificityindetecting

individualswith reducedbonedensity (T score<–1) ranging from40.8%to100%and

from47%to88%,respectively.

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In the sameway, antegonial index, gonial indexandmandibular ratiohave shownan

insufficientsignificanceaspredictortools.Literaturedataonthese“secondary”indices

ispoor,becausealltheavailablemeta-analysishavebeenperformedonMCW,PMIand

KI. Moreover, several studies reporting a positive correlation between skeletal and

jawboneBMDhavenotdistinguishedbetweenosteoporoticandhealthypatientswhen

reporting the correlation coefficients, thus further limiting the possibility of drawing

robustconclusions.

Anotherlimitationwefoundduringtheliteraturereviewwasrelatedtothefactthatall

studieshaveconsideredonlymandibulardata,withouttakingintoaccountthemaxilla.It

is well known that in osteoporotic subjects bone loss is not uniform and that the

trabecularboneisearlierandmoredeeplyaffectedthanthecorticalbone(29,178).The

mandiblehasabetterresemblancewiththefemurneck(179,180),wherefracturesare

primarilycausedbyalossincorticalratherthantrabecularbone(181,182).Considering

thatthemaxillaismainlymadeoftrabecularbone,itislikelythatbonedensitymeasured

atthissitewouldhavebeenbetterrelatedtovertebralosteoporosis.However,thelack

ofstablereferralpoints(likethementalforameninthemandible)makesitchallenging

toevaluatestandardizedsitesinthemaxilla.

When dealingwith jawbones it should also be kept inmind that they display unique

anatomic characteristics in comparison with other bones of the skeleton, owing for

exampletotheirspecialrelationshipwithteethandthedistinctionbetweenthemore

stablebasalboneandthealveolarbone,whichatrophiesafterteetharelost(183,184).

Itmaybehypothesizedthattheseandotheranatomical/physiologicalpeculiaritiesofthe

jawscansomehowaccountfordifferencesinbonemetabolismresponse(185).

�

6.2 PERIODONTALEXAMINATIONDATAANDBMD

Periodontitis is an infection-induced inflammationof the structures around the tooth

resultinginlossofitssofttissueattachmentandsurroundingbonemass,finallyresulting

intoothloss.Arelationbetweenosteoporosisandperiodontitishasalsobeenpostulated

in literaturesincemanyyears.Osteoporosisbeingasystemicdisease, leads to lossof

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bone stocknotonly fromspineandappendicular skeletonbut also from thealveolar

bone. Thus, osteoporosis is expected to hasten the process of bone loss in chronic

periodontitis(186).

Osteoporosisiswellknowninpostmenopausalwomenwithprevalenceashighas50%

(187) and the postmenopausal status is also associated with increased severity of

periodontitis with prevalence as high as 30% (102, 188). Periodontitis is clinically

measuredintermsofCAL,PPD,andalveolarboneloss.Otherperiodontalindicesthat

researchers have to take into account are recession, tooth mobility, furcations

involvementandtoothloss.

Inthepresentstudy,all theaforementionedparametershavebeenrecordedfrom70

patientsinordertoanalyzetheprevalenceofperiodontaldiseaseinapopulationofpost-

menopausal women. The correlation between periodontal status and BMD has been

statisticallyinvestigatedcomparingperiodontalindicesandtheworstt-scorevalue.

Pocket probing depth has been recordedwith a 6-point sounding and a group of 51

patientshasbeenanalyzed.Astatisticalsignificantcorrelationhasbeendemonstrated

betweenperiodontalprobingdepth>5mmandBMDt-scores.Itisofprimaryimportance

tounderlinethatthedirectionofthecorrelationhasbeentowardsthehealthygroup.

These data show that osteoporotic patients exhibit a better periodontal condition in

termsofperiodontalsoundinginrespectofthepatientswithat-score>-2,5.

Similarly, clinical attachment loss, considered as PPD added to REC value, has been

correlatedtothediagnosisofosteoporosis.Siteshavebeenclassifiedinthreeclusters

accordingtheprogressiveclinicalattachment loss.ThegroupwithCALof1-2mmhas

beenconsideredasperiodontalhealthandthecorrelationhasshownnosignificance,

similarly, thegroupwithCAL>5mm, representativeof thepopulationwitha severe

periodontaldestructionhasshownapoorcorrelation.

Interestingly, the groupwithCALof 3-4mm, representative of the larger part of the

populationhasshownastatisticallysignificanceifcorrelatedtoBMD.Accordinglytothe

PPDvalue,thecorrelationistowardsthepatientsdiagnosedashealthy.

These two parameters are considered, in the scientific literature, two of the most

predictabletoolstoidentifyacorrelationbetweenosteoporosisandperiodontitis(189).

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Several studies have demonstrated that postmenopausal women, with lower bone

mineraldensity,haveahighernumberofDecayed-Missing-Filled-Teethand,astheage

of the postmenopausal subject increases, the number of teeth decreases and the

Decayed-Missing-Filled-Teethscoreincreases(189).Oldosteoporoticwomenmostlikely

haveperiodontaldiseasecomparedtothosewithoutosteoporosis.Anincreasinginage

andadecreasinginfemalesexualhormonesarerelatedtoanincreasinginboneloss.

Oralsigns,BodyMassIndexandagecanbeusedascriteriaindicatingosteoporosis’risk.

ArecentsystematicreviewbyGoyaletal.hasfavoredastrongassociationbetweenthe

centralBMDandCAL.

Findingsfromthisresearchareindisagreementwithdataoftheliterature,andPPD³5

andCAL3-4mmhavebeendemonstratedassociatedtoaconditionofhealthysystemic

bonedensity,andconsequently,osteoporoticpatientshaveshownbetterperiodontal

conditions(190).Theseresultscouldseemcontroversialbutitiscrucialtoanalyzetwo

key-factors: the recruiting pattern and the sample size. All the patients have been

enrolledinaDentalhospital,anditisplausiblethattheyhavebeenusedtoattendthe

dentalhospitaltoreceivedentaltreatments.Inaddition,itisplausiblethatpatientsthat

have receivedadiagnoseofosteoporosisand, in severalcases,a treatmentplan that

provides the assumption of medications such as bisphosphonates, have a particular

attentionandcaretotheirhealth.Theoralhealthofthistypeofpatientsisperiodically

controlledand theperiodontal status isusuallymaintainedwithaproperperiodontal

recallscheme.

Thesecondaspecttotakeintoaccountisthepowerofthestudy.Thesamplesizeofthe

researchhasbeensettoobtainastatisticalpoweraccordingtothefindings fromthe

reviewofCalciolarietal.andithasbeenbasedontheprimaryoutcomes:toassessthe

feasibilityofusingdentalpanoramicindicestoscreenforpost-menopausalosteoporosis

and to assess the sensitivity and specificity of quantitative and qualitative panoramic

indices (165). For this reason, the study is underpowered in assessing if periodontal

indices are correlated to BMD. Moreover, at the moment of the data analysis, the

recruitment has been still ongoing and only data from 70 patients were available.

Accordingtotheseconsiderations,alltheresultsfromtheperiodontaldataexamination

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havetobeconfirmedwithfurtherstudieswitha largersampleofpatientsandwitha

strictrecruitmentoutline.

Regardingtheothersperiodontalindices,onlythenumberandthepercentageoftooth

losshavedemonstratedacorrelationthathasbeenconfirmedstatistically.Inthiscase

thetendencyofmissingteethhasbeentowardstheosteoporoticgroups.Thesedataare

in contrast to the aforementioned periodontal findings, and this strengthen the

hypothesisthatthesampleistoosmalltodrawmeaningfulconclusions.

6.3 SAMPLESIZEANDRECRUITMENTPATTERN

Aspreviouslydescribed,therecruitmentofthepatienthasbeendonewithinapoolof

post-menopausal women attending the Centre of Dentistry at Parma University.

Accordingtothe findingshereshown, it isplausiblethatarecruitment-centrerelated

bias could be present and of some importance. A large portion of the patients, that

regularlyattendsthedentalhospital,followsapersonalizedrecallprograminorderto

controltheperiodontalstatusovertime.Inparticular,periodontalcompromisedpatients

undergoasupportiveperiodontaltherapyaccordingtotheperiodontalriskassessment

tool.

Furthermore, the study has been designed to reach a statistical power of 80 % in

identifyingmorphometricpanoramicindicesastoolstodiagnoseosteoporosis,according

tothedatafromthereviewbyCalciolariet.al(2015),andthesamplenumberhasbeen

setat124(165).Asevidencedbythecriticalreviewoftheliterature,thepropersample

sizetoinvestigatetheprevalenceofperiodontaldiseaseinosteoporoticpatientshasto

bewider.Moreover,sincethestudyisstillgoing,only70patientshavebeenincludedin

thestudy,makingthesamplesizeevenlesspowered.Forthesereasons,furtherstudies

withapropersamplesizecalculationandwithoutpopulationselectionbiasesareneeded

andarealreadyongoing,inordertoobtainsignificativeresults.

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6.4 CONFUNDINGFACTORS

Someconfoundingfactorscouldbeconsideredtobetterunderstandtheresultsandto

drawsensibleconclusions.

6.4.1 AgeTheinclusioncriteriaofthestudyhavesetat65yearsoldtheminimumagetobeeligible

forthestudy.ThishasbeendecidedaccordingtoItaliannationalhealthsystemguidelines

that considers above 65 years, the cut-off age from which consider the risk of

osteoporosisashigh.Itisimportanttoknowthat50yearsoldpost-menopausalwomen

couldbeeasilyfindwithinanormalpopulationand,withtheseinclusioncriteria,acluster

ofpatientfrom50to65yearsoldarenotinvolved.Furthermore,olderpatientsshow

different interfering medical conditions such as, bone metabolism, medications,

concomitantpathologies,dentalstatus,toothloss,etc.andthisaspectcouldbecrucial

in a statistical analysis. In fact, according to the literature a 30% prevalence of

osteoporosisamongstpost-menopausalwomenattendingadentalhospital,hasbeen

speculated. Anyhow, considering the age of the eligible patients, the prevalence of

osteoporosisinthepopulationcouldbehigherthanthe30%.Thisconsiderationhasbeen

confirmedbyourdatathathaveshownaprevalenceofosteoporoticpatientswithinthe

sampleof50%.

Attheendofthestudy,aFishertestcouldbenecessaryinordertoexcludetheageasa

confoundingvariable.

6.4.2 Smoke

Theavailableliteratureaboutpanoramicindicesdoesnottakeintoaccountthecondition

ofsmoker/non-smokerofthepatients.However,smokeisconsideredasariskfactorfor

theprogressionof theperiodontitisandhasbeendemonstratedstrictly correlated to

periodontal conditions. For this reason, smoke couldbe considered as a confounding

variableintheanalysisofthecorrelationbetweenperiodontalstatusandBMDbutthe

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Fishertesthasshownnocorrelation.Nevertheless,thesmallsamplesizesuggeststhata

secondtestexecutedonalargerpopulationcouldbemoreeffective.

6.4.3 MedicationsDuringthepastdecade, increasingconcernhasdevelopedtowardsasevere,although

rare,complicationofanti-osteoporoticdrugsnamedosteonecrosisofthejaw(ONJ).

It is usually associated to bisphosphonates, in particular nitrogenous-based and

intravenousoneandthe firstdocumentedONJsdateback to2003andsince thenan

increasingnumberofpublicationshasfocusedonthisproblem.Sincethen,otherdrugs,

allable to inhibitbone resorption, suchasdenosumaborThor’s inhibitorshavebeen

consideredinvolvedinthepathogenesisofONJs(191).Recentlypubblishedpapershave

demonstratedacorrelationbetweenBP’sandbetterperiodontalconditions.

Theexactmechanism leading toONJ is still unknown, aswell as the reasonwhy this

conditiondevelopsonlyinthemaxilla-mandibularcomplex.Microdamageaccumulation,

infectionandsofttissuetoxicity(atleastforBPs)haveallbeensuggestedtoplayarole

inthedevelopmentofONJs(192).Itisalsoimportanttothinkthattheoralcavitypresents

withuniquecharacteristics compared tootherbonesof thebody,as thepresenceof

teethallowsadirectconnectionbetweentheboneandtheexterior.Moreover,dental

and periodontal infections and dento-alveolar trauma may be able to trigger this

condition(193).Itisimportanttonoticethatrecentlypubblishedpapershavesuggested

apossiblecorrelationbetweenBFsandbetterperiodontalconditions(194).Forallthese

reasons, apossible roleofBPs in influencing the correlationbetweenbodymassand

jawbonescouldbemoreinvestigatedbut,tostatisticallydemonstrateanyconnection,

thesampleneedtobeincreased.

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7 CONCLUSIONS

127

According to our findings, although it is not indicated to prescribe an OPG with the

primary aim to screen for osteopenia/osteoporosis, whenever a pantomograph is

available,MCW,andKIcanbeahelpfulandeasilyusabletoolforthedentisttointercept

patientsatriskofreducedBMD,sincethisdiseasecanseverelyinterferewithanydental

treatment.Moreover,consideringthehighnegativepredictivevalueofthecombination

oftwoindices,thedentistcaneasilyexcludehealthypatientsandguidethepatientat

riskinaspecialisticdiagnosticpathway.

Thepossibilitytousedentalpanoramicradiographstoidentifypreviouslyundiagnosed

osteoporoticpatientsissuggestiveandseemstobesupportedbythesystematicreview

presentedinChapter3,althoughtheaveragequalityoftheavailablestudiesisnothigh.

Future studies should therefore account for confounding variables (e.g.medications,

concomitantdiseasesaffectingbonemetabolism,demographics),ensurethatexaminers

are blind to the skeletal BMD of the patients, and accurately evaluate the kappa of

agreement for intra- and inter-examiner reliability. The optimal cut-off has been

investigatedinthisstudy,byapplyingROCcurvesandtakingintoconsiderationnotonly

the sensitivity/specificity of the index, but also the positive and negative predictive

values,whichvarywiththeprevalenceofthediseaseandmayhaveamoremeaningful

clinical impact. Furthermore, the possibility to combine panoramic indices with well-

knownrisk factors forosteoporosisshouldbeaddressedby futurestudies inorder to

increasetheiraccuracyandthestrengthofthesesuggestions.Finally,thepossibilityto

measureindicesintheupperjawneedstobeinvestigated,althoughthelackofstable

anatomicreferencepointsinthemaxillamightbedifficulttoovercome.

Thewillingnessofgeneraldentiststotakepartintrainingsessionsandthewillingnessof

patientstobereferredtotheirGPortoaspecialistfollowingadentalappointment,as

wellasareferralpathwayfromgeneraldentistsdirectlytoGPsorosteoporoticspecialists

shouldbealsoevaluatedbyfutureclinicalprojects.Inthelongrun,aprospectivestudy

correlating panoramic indices to the risk of developing fractures, which are the real

burdenofosteoporosis,wouldaddadditionalstrengthtotheuseofthesetools,which

128

mightpotentiallybeaddedtoexistingfractureriskassessmenttools,suchasFRAXorthe

ItalianversionDeFRA.

RegardingthecorrelationbetweenperiodontalstatusandBMDitisclearthatthepresent

study is at the moment still unpowered. Further ongoing studies setting a proper

statisticalpowerandtakingintoaccounttheconfoundingvariablessuchassmoke,age

and enrolment facility are needed. In particular, PPD and CAL need to be more

investigatedconsideringthedifferencebetweenliteraturedataandthefindingsfromthis

study.Moreover,numberandpercentageoftoothlossareperiodontaldatathatcould

be related to the t-scorevalue. In conclusion,all theseperiodontal indices couldgive

meaningful informationbuttheenrolmentbiascouldbeavoidedandtherecruitment

hastobemorerepresentativeoftherealpopulation.

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8 REFERENCES

130

1. Consensus development conference: diagnosis, prophylaxis, and treatment ofosteoporosis.AmJMed.1993;94(6):646-50.2. Clinician’sGuidetoPreventionandTreatmentofOsteoporosis.Washington,DC:NationalOsteoporosisFoundation.2014.3. Osteoporosis.Clinicalguidelineforpreventionandtreatment.Executivesummary.;2014.4. KanisJA,DelmasP,BurckhardtP,CooperC,TorgersonD.Guidelinesfordiagnosisandmanagement of osteoporosis. The European Foundation for Osteoporosis and Bone Disease.OsteoporosInt.1997;7(4):390-406.5. KanisJA,McCloskeyEV,JohanssonH,OdenA,MeltonLJ,3rd,KhaltaevN.Areferencestandardforthedescriptionofosteoporosis.Bone.2008;42(3):467-75.6. Kanis JAobotWSG.Assessment of osteoporosis at the primary health-care level.WHOCollaboratingCentre,UniversityofSheffield,UK.2008.7. LookerAC,WahnerHW,DunnWL,CalvoMS,HarrisTB,HeyseSP,etal.UpdateddataonproximalfemurboneminerallevelsofUSadults.OsteoporosisInternational.1998;8(5):468-89.8. KanisJA,McCloskeyEV,JohanssonH,CooperC,RizzoliR,ReginsterJY.Europeanguidancefor the diagnosis andmanagement of osteoporosis in postmenopausalwomen.Osteoporosisinternational:ajournalestablishedasresultofcooperationbetweentheEuropeanFoundationforOsteoporosisandtheNationalOsteoporosisFoundationoftheUSA.2013;24(1):23-57.9. LewieckiEM,WattsNB,McClungMR,PetakSM,BachrachLK,ShepherdJA,etal.Officialpositionsoftheinternationalsocietyforclinicaldensitometry.JournalofClinicalEndocrinology&Metabolism.2004;89(8):3651-5.10. Leslie WD, Lix LM, Tsang JF, Caetano PA. Single-site vs multisite bone densitymeasurementforfractureprediction.Archivesofinternalmedicine.2007;167(15):1641-7.11. Blake GM, Patel R, Knapp KM, Fogelman I. Does the combination of two BMDmeasurements improve fracture discrimination? Journal of bone and mineral research : theofficialjournaloftheAmericanSocietyforBoneandMineralResearch.2003;18(11):1955-63.12. NjehCF,FuerstT,HansD,BlakeGM,GenantHK.Radiationexposure inbonemineraldensityassessment.ApplRadiatIsot.1999;50(1):215-36.13. InternationalSocietyforClinicalDensitometry.2013OfficialPostions-Adult.;2013.14. Johnell O, Hertzman P. What evidence is there for the prevention and screening ofosteoporosis?WHORegionalOfficeforEurope'sHealthEvidenceNetwork(HEN).Copenhagen;2006.15. Clinician’sGuide toPreventionandTreatmentofOsteoporosis.NationalOsteoporosisFoundation.Washington,DC;2014.16. MarcusR,FeldmanD,DempsterDW,LuckeyM,CauleyJA.Osteoporosis.FourthEdition.UnitedSatesofAmerica:ElsevierInc.;2013.17. RiggsBL,KhoslaS,MeltonLJ,3rd.Aunitarymodelforinvolutionalosteoporosis:estrogendeficiencycausesbothtypeIandtypeIIosteoporosisinpostmenopausalwomenandcontributestobonelossinagingmen.JBoneMinerRes.1998;13(5):763-73.18. KhoslaS,OurslerMJ,MonroeDG.Estrogenandtheskeleton.Trends inendocrinologyandmetabolism:TEM.2012;23(11):576-81.19. Hernlund E, Svedbom A, Ivergard M, Compston J, Cooper C, Stenmark J, et al.OsteoporosisintheEuropeanUnion:medicalmanagement,epidemiologyandeconomicburden.

131

AreportpreparedincollaborationwiththeInternationalOsteoporosisFoundation(IOF)andtheEuropeanFederationofPharmaceuticalIndustryAssociations(EFPIA).Archivesofosteoporosis.2013;8(1-2):136.20. BoneHealthandOsteoporosis:areportoftheSurgeonGeneral.Rockville(MD):OfficeoftheSurgeonGeneral;2004.Availablefrom:http://www.ncbi.nlm.nih.gov/books/NBK45513/.21. CooperC.Thecripplingconsequencesoffracturesandtheirimpactonqualityoflife.TheAmericanjournalofmedicine.1997;103(2A):12S-7S;discussion7S-9S.22. Lu-Yao GL, Baron JA, Barrett JA, Fisher ES. Treatment and survival among elderlyAmericanswithhipfractures:apopulation-basedstudy.AmJPublicHealth.1994;84(8):1287-91.23. JohnellO,Kanis JA.Anestimateof theworldwideprevalenceanddisabilityassociatedwith osteoporotic fractures. Osteoporosis international : a journal established as result ofcooperationbetweentheEuropeanFoundationforOsteoporosisandtheNationalOsteoporosisFoundationoftheUSA.2006;17(12):1726-33.24. RiggsBL,MeltonIiiLJ,3rd,RobbRA,CampJJ,AtkinsonEJ,PetersonJM,etal.Population-basedstudyofageandsexdifferencesinbonevolumetricdensity,size,geometry,andstructureat different skeletal sites. Journal of bone and mineral research : the official journal of theAmericanSocietyforBoneandMineralResearch.2004;19(12):1945-54.25. RiggsBL,MeltonLJ,RobbRA,CampJJ,AtkinsonEJ,McDanielL,etal.Apopulation-basedassessmentof ratesofbone lossatmultipleskeletal sites:evidence for substantial trabecularbone loss inyoungadultwomenandmen. Journalofboneandmineral research : theofficialjournaloftheAmericanSocietyforBoneandMineralResearch.2008;23(2):205-14.26. SlovikD.Screeningforosteoporosisinpostmenopausalwomen.In:SonyaSeigafuseRSe,editor.Primarycaremedicine:officeevaluationandmanagementof theadultpatient6thed.Philadelphia:LippincottWilliams&Wilkins2011.p.1006-8.27. Lindsay R, Hart DM, Aitken JM, MacDonald EB, Anderson JB, Clarke AC. Long-termpreventionofpostmenopausalosteoporosisbyoestrogen.Evidenceforanincreasedbonemassafterdelayedonsetofoestrogentreatment.Lancet.1976;1(7968):1038-41.28. Nilas L, ChristiansenC. Ratesof bone loss innormalwomen: evidenceof acceleratedtrabecularbonelossafterthemenopause.EurJClinInvest.1988;18(5):529-34.29. KhoslaS.Pathogenesisofage-relatedbonelossinhumans.ThejournalsofgerontologySeriesA,Biologicalsciencesandmedicalsciences.2013;68(10):1226-35.30. SiposW, Pietschmann P, RaunerM, Kerschan-Schindl K, Patsch J. Pathophysiology ofosteoporosis.WienMedWochenschr.2009;159(9-10):230-4.31. BonoCM,EinhornTA.Overviewofosteoporosis:pathophysiologyanddeterminantsofbonestrength.EurSpineJ.2003;12Suppl2:S90-6.32. EriksenEF,ColvardDS,BergNJ,GrahamML,MannKG,SpelsbergTC,etal.Evidenceofestrogenreceptorsinnormalhumanosteoblast-likecells.Science.1988;241(4861):84-6.33. OurslerMJ,OsdobyP,PyfferoenJ,RiggsBL,SpelsbergTC.Avianosteoclastsasestrogentargetcells.ProcNatlAcadSciUSA.1991;88(15):6613-7.34. Syed F, Khosla S. Mechanisms of sex steroid effects on bone. Biochem Biophys ResCommun.2005;328(3):688-96.

132

35. Charatcharoenwitthaya N, Khosla S, Atkinson EJ, McCready LK, Riggs BL. Effect ofblockade of TNF-alpha and interleukin-1 action on bone resorption in early postmenopausalwomen.JBoneMinerRes.2007;22(5):724-9.36. RogersA,EastellR.Theeffectof17beta-estradiolonproductionofcytokinesinculturesofperipheralblood.Bone.2001;29(1):30-4.37. Jilka RL. Cytokines, bone remodeling, and estrogen deficiency: a 1998 update. Bone.1998;23(2):75-81.38. McLean RR. Proinflammatory cytokines and osteoporosis. Curr Osteoporos Rep.2009;7(4):134-9.39. CosmanF,ShenV,XieF,SeibelM,RatcliffeA,LindsayR.Estrogenprotectionagainstboneresorbingeffectsofparathyroidhormoneinfusion.Assessmentbyuseofbiochemicalmarkers.AnnInternMed.1993;118(5):337-43.40. KraichelyDM,MacDonaldPN.TranscriptionalactivationthroughthevitaminDreceptorinosteoblasts.FrontBiosci.1998;3:d821-33.41. SakaiS,TakaishiH,MatsuzakiK,KanekoH,FurukawaM,MiyauchiY,etal.1-Alpha,25-dihydroxy vitamin D3 inhibits osteoclastogenesis through IFN-beta-dependent NFATc1suppression.JBoneMinerMetab.2009;27(6):643-52.42. Kassem M, Marie PJ. Senescence-associated intrinsic mechanisms of osteoblastdysfunctions.Agingcell.2011;10(2):191-7.43. VermaS,RajaratnamJH,DentonJ,HoylandJA,ByersRJ.Adipocyticproportionofbonemarrow is inversely related to bone formation in osteoporosis. Journal of clinical pathology.2002;55(9):693-8.44. RodriguezJP,AstudilloP,RiosS,PinoAM.Involvementofadipogenicpotentialofhumanbone marrow mesenchymal stem cells (MSCs) in osteoporosis. Curr Stem Cell Res Ther.2008;3(3):208-18.45. Lane NE. Epidemiology, etiology, and diagnosis of osteoporosis. American Journal ofObstetricsandGynecology.2006;194(2):S3-S11.46. Dawson-HughesB,KrallEA,HarrisS.Riskfactorsforbonelossinhealthypostmenopausalwomen.Osteoporosisinternational:ajournalestablishedasresultofcooperationbetweentheEuropeanFoundation forOsteoporosisandtheNationalOsteoporosisFoundationof theUSA.1993;3Suppl1:27-31.47. Haffajee AD, Socransky SS. Microbial etiological agents of destructive periodontaldiseases.Periodontol2000.1994;5:78-111.48. Loe H. The Gingival Index, the Plaque Index and the Retention Index Systems. JPeriodontol.1967;38(6):Suppl:610-6.49. SilnessJ,LoeH.PeriodontalDiseaseinPregnancy.Ii.CorrelationbetweenOralHygieneandPeriodontalCondtion.ActaOdontolScand.1964;22:121-35.50. AinamoJ,BayI.Problemsandproposalsforrecordinggingivitisandplaque.IntDentJ.1975;25(4):229-35.51. LangNP,JossA,OrsanicT,GusbertiFA,SiegristBE.Bleedingonprobing.Apredictorfortheprogressionofperiodontaldisease?JClinPeriodontol.1986;13(6):590-6.

133

52. ClaffeyN,NylundK,KigerR,GarrettS,EgelbergJ.Diagnosticpredictabilityofscoresofplaque, bleeding, suppuration andprobingdepth for probing attachment loss. 3 1/2 years ofobservationfollowinginitialperiodontaltherapy.JClinPeriodontol.1990;17(2):108-14.53. BaderstenA,NilveusR,EgelbergJ.Scoresofplaque,bleeding,suppurationandprobingdepth to predict probing attachment loss. 5 years of observation following nonsurgicalperiodontaltherapy.JClinPeriodontol.1990;17(2):102-7.54. HampSE,NymanS,LindheJ.Periodontaltreatmentofmultirootedteeth.Resultsafter5years.JClinPeriodontol.1975;2(3):126-35.55. Tarnow DP. An exquisite periodontal approach: flap designs for the insertion andrecoveryofroot-formimplants.DentImplantolUpdate.1994;5(10):78-80.56. MillerSC.Theperiodontist'sviewofocclusion.JDentMed.1950;5(3):66-9.57. BennDK.Limitationsofthedigitalimagesubtractiontechniqueinassessingalveolarbonecrest changes due to misalignment errors during image capture. Dentomaxillofac Radiol.1990;19(3):97-104.58. LoeH,TheiladeE,JensenSB.ExperimentalGingivitisinMan.JPeriodontol.1965;36:177-87.59. TrombelliL.Susceptibilitytogingivitis:awaytopredictperiodontaldisease?OralHealthPrevDent.2004;2Suppl1:265-9.60. HolmstrupP.Non-plaque-inducedgingivallesions.AnnPeriodontol.1999;4(1):20-31.61. LindheJ,SocranskyS,NymanS,WestfeltE,HaffajeeA.Effectofageonhealingfollowingperiodontaltherapy.JClinPeriodontol.1985;12(9):774-87.62. LoeH.Researchonoraldiseasesandits impactondentaleducationandpractice.AdvDentRes.1988;2(2):199-203.63. Socransky SS, Haffajee AD. The Bacterial Etiology of Destructive Periodontal Disease:CurrentConcepts.JPeriodontol.1992;63Suppl4S:322-31.64. O'ReillyPG,ClaffeyNM.Ahistoryoforalsepsisasacauseofdisease.Periodontol2000.2000;23:13-8.65. D'AiutoF,ReadyD,TonettiMS.PeriodontaldiseaseandC-reactiveprotein-associatedcardiovascularrisk.JPeriodontalRes.2004;39(4):236-41.66. Giancola G, Granati B, Chiozza ML, Zorzi C, Piovesan A. [Effect of obstructivemalformationsonthegastrointestinaltractonbilirubinlevelsinnewborninfants].PediatrMedChir.1982;4(1-2):115-8.67. ShlossmanM,KnowlerWC,PettittDJ,GencoRJ.Type2diabetesmellitusandperiodontaldisease.JAmDentAssoc.1990;121(4):532-6.68. KiranM,ArpakN,UnsalE,ErdoganMF.Theeffectof improvedperiodontalhealthonmetaboliccontrolintype2diabetesmellitus.JClinPeriodontol.2005;32(3):266-72.69. DeRisoAJ,2nd,LadowskiJS,DillonTA,JusticeJW,PetersonAC.Chlorhexidinegluconate0.12% oral rinse reduces the incidence of total nosocomial respiratory infection andnonprophylactic systemic antibiotic use in patients undergoing heart surgery. Chest.1996;109(6):1556-61.70. HorningGM,CohenME.Necrotizingulcerativegingivitis,periodontitis,andstomatitis:clinicalstagingandpredisposingfactors.JPeriodontol.1995;66(11):990-8.

134

71. Kristerson L, Andreasen JO. Influence of root development on periodontal andpulpalhealingafterreplantationofincisorsinmonkeys.IntJOralSurg.1984;13(4):313-23.72. Lilienfeld DE. "The greening of epidemiology": sanitary physicians and the LondonEpidemiologicalSociety(1830-1870).BullHistMed.1978;52(4):503-28.73. Armitage GC. Development of a classification system for periodontal diseases andconditions.AnnPeriodontol.1999;4(1):1-6.74. TelesR,BenechaHK,PreisserJS,MossK,StarrJR,CorbyP,etal.Modellingchangesinclinical attachment loss to classify periodontal disease progression. J Clin Periodontol.2016;43(5):426-34.75. Papapanou PN. Systemic effects of periodontitis: lessons learned from research onatheroscleroticvasculardiseaseandadversepregnancyoutcomes.IntDentJ.2015;65(6):283-91.76. KassebaumNJ,BernabeE,DahiyaM,BhandariB,MurrayCJ,MarcenesW.GlobalBurdenofSevereToothLoss:ASystematicReviewandMeta-analysis.JDentRes.2014;93(7Suppl):20S-8S.77. MeyleJ,ChappleI.Molecularaspectsofthepathogenesisofperiodontitis.Periodontol2000.2015;69(1):7-17.78. SocranskySS,HaffajeeAD,SmithGL,DzinkJL.Difficultiesencounteredinthesearchfortheetiologicagentsofdestructiveperiodontaldiseases.JClinPeriodontol.1987;14(10):588-93.79. Roberts FA,DarveauRP.Microbial protectionand virulence inperiodontal tissueas afunction of polymicrobial communities: symbiosis and dysbiosis. Periodontol 2000.2015;69(1):18-27.80. ZanderHA,HazenSP,ScottDB.Mineralizationofdentalcalculus.ProcSocExpBiolMed.1960;103:257-60.81. TheiladeJ.ElectronMicroscopicStudyofCalculusAttachmenttoSmoothSurfaces.ActaOdontolScand.1964;22:379-87.82. WaerhaugJ.Effectofroughsurfacesupongingivaltissue.JDentRes.1956;35(2):323-5.83. HendersonB,TabonaP,PooleS,NairSP.Cloningandexpressionof theActinobacillusactinomycetemcomitans thioredoxin (trx) geneandassessmentof cytokine inhibitory activity.InfectImmun.2001;69(1):154-8.84. NewmanHN.Theapicalborderofplaqueinchronicinflammatoryperiodontaldisease.BrDentJ.1976;141(4):105-13.85. Genco RJ, Van Dyke TE, Park B, Ciminelli M, Horoszewicz H. Neutrophil chemotaxisimpairment in juvenile periodontitis: evaluation of specificity, adherence, deformability, andserumfactors.JReticuloendothelSoc.1980;28(Suppl):81s-91s.86. ArakawaS,NakajimaT, IshikuraH,IchinoseS, IshikawaI,TsuchidaN.Novelapoptosis-inducing activity in Bacteroides forsythus: a comparative study with three serotypes ofActinobacillusactinomycetemcomitans.InfectImmun.2000;68(8):4611-5.87. RodenburgJP,vanWinkelhoffAJ,WinkelEG,GoeneRJ,AbbasF,deGraffJ.OccurrenceofBacteroidesgingivalis,BacteroidesintermediusandActinobacillusactinomycetemcomitansinsevereperiodontitisinrelationtoageandtreatmenthistory.JClinPeriodontol.1990;17(6):392-9.

135

88. Haffajee AD, Bogren A, Hasturk H, Feres M, Lopez NJ, Socransky SS. Subgingivalmicrobiota of chronic periodontitis subjects from different geographic locations. J ClinPeriodontol.2004;31(11):996-1002.89. Tanner AC, Haffer C, Bratthall GT, Visconti RA, Socransky SS. A study of the bacteriaassociatedwithadvancingperiodontitisinman.JClinPeriodontol.1979;6(5):278-307.90. Socransky SS, Haffajee AD, Cugini MA, Smith C, Kent RL, Jr. Microbial complexes insubgingivalplaque.JClinPeriodontol.1998;25(2):134-44.91. DzinkJL,SocranskySS,HaffajeeAD.Thepredominantcultivablemicrobiotaofactiveandinactivelesionsofdestructiveperiodontaldiseases.JClinPeriodontol.1988;15(5):316-23.92. Haffajee AD, Teles RP, Socransky SS. Association of Eubacterium nodatum andTreponemadenticolawithhumanperiodontitislesions.OralMicrobiolImmunol.2006;21(5):269-82.93. Page RC, Kornman KS. The pathogenesis of human periodontitis: an introduction.Periodontol2000.1997;14:9-11.94. GrossiSG,ZambonJJ,HoAW,KochG,DunfordRG,MachteiEE,etal.Assessmentofriskforperiodontaldisease.I.Riskindicatorsforattachmentloss.JPeriodontol.1994;65(3):260-7.95. YilmazO,LeeKL.Theinflammasomeanddangermoleculesignaling:atthecrossroadsofinflammationandpathogenpersistenceintheoralcavity.Periodontol2000.2015;69(1):83-95.96. CicchettiG,AllenPG,GlogauerM.Chemotacticsignalingpathwaysinneutrophils:fromreceptortoactinassembly.CritRevOralBiolMed.2002;13(3):220-8.97. Kleinbaum J, Shamoon H. Selective counterregulatory hormone responses after oralglucoseinman.JClinEndocrinolMetab.1982;55(4):787-90.98. HillRB,Jr.,AndersonRE.Changeandclinicalresponsibilityinpathology.ArchPatholLabMed.1977;101(12):621-2.99. Borrell LN,PapapanouPN.Analyticalepidemiologyofperiodontitis. JClinPeriodontol.2005;32Suppl6:132-58.100. DyeBA,FisherMA,YellowitzJA,FryarCD,VargasCM.Receiptofdentalcare,dentalstatusandworkforce inU.S.nursinghomes:1997NationalNursingHomeSurvey.SpecCareDentist.2007;27(5):177-86.101. PapapanouPN,Lindhe J,Sterrett JD,EnerothL.Considerationson thecontributionofageingtolossofperiodontaltissuesupport.JClinPeriodontol.1991;18(8):611-5.102. AlbandarJM.Globalriskfactorsandriskindicatorsforperiodontaldiseases.Periodontol2000.2002;29:177-206.103. NibaliL,D'AiutoF,DonosN,GriffithsGS,ParkarM,TonettiMS,etal.Associationbetweenperiodontitis and common variants in the promoter of the interleukin-6 gene. Cytokine.2009;45(1):50-4.104. BrettPM,ZygogianniP,GriffithsGS,TomazM,ParkarM,D'AiutoF,etal.Functionalgenepolymorphismsinaggressiveandchronicperiodontitis.JDentRes.2005;84(12):1149-53.105. Diehl SR, Wang Y, Brooks CN, Burmeister JA, Califano JV, Wang S, et al. Linkagedisequilibrium of interleukin-1 genetic polymorphisms with early-onset periodontitis. JPeriodontol.1999;70(4):418-30.

136

106. Huynh-Ba G, Lang NP, Tonetti MS, Salvi GE. The association of the composite IL-1genotypewithperiodontitisprogressionand/ortreatmentoutcomes:asystematicreview.JClinPeriodontol.2007;34(4):305-17.107. HerreraD,SanzM,JepsenS,NeedlemanI,RoldanS.Asystematicreviewontheeffectofsystemicantimicrobialsasanadjuncttoscalingandrootplaninginperiodontitispatients.JClinPeriodontol.2002;29Suppl3:136-59;discussion60-2.108. Kinane DF, Chestnutt IG. Smoking and periodontal disease. Crit Rev Oral Biol Med.2000;11(3):356-65.109. KinaneDF,RadvarM.Theeffectofsmokingonmechanicalandantimicrobialperiodontaltherapy.JPeriodontol.1997;68(5):467-72.110. Labriola A, Needleman I, Moles DR. Systematic review of the effect of smoking onnonsurgicalperiodontaltherapy.Periodontol2000.2005;37:124-37.111. GencoRJ,LoeH.Theroleofsystemicconditionsanddisorders inperiodontaldisease.Periodontol2000.1993;2:98-116.112. LallaE,ParkDB,PapapanouPN,LamsterIB.OraldiseaseburdeninNorthernManhattanpatientswithdiabetesmellitus.AmJPublicHealth.2004;94(5):755-8.113. TervonenT,KarjalainenK.Periodontaldiseaserelatedtodiabeticstatus.Apilotstudyoftheresponsetoperiodontaltherapyintype1diabetes.JClinPeriodontol.1997;24(7):505-10.114. Saito T, Shimazaki Y, Sakamoto M. Obesity and periodontitis. N Engl J Med.1998;339(7):482-3.115. GarciaRI,HenshawMM,KrallEA.Relationshipbetweenperiodontaldiseaseandsystemichealth.Periodontol2000.2001;25:21-36.116. TezalM,Wactawski-WendeJ,GrossiSG,HoAW,DunfordR,GencoRJ.Therelationshipbetween bone mineral density and periodontitis in postmenopausal women. J Periodontol.2000;71(9):1492-8.117. Weyant RJ, PearlsteinME, Churak AP, Forrest K, Famili P, Cauley JA. The associationbetween osteopenia and periodontal attachment loss in older women. J Periodontol.1999;70(9):982-91.118. Wactawski-Wende J. Periodontal diseases and osteoporosis: association andmechanisms.AnnPeriodontol.2001;6(1):197-208.119. BrennanRM,GencoRJ,HoveyKM,TrevisanM,Wactawski-WendeJ.Clinicalattachmentloss,systemicbonedensity,andsubgingivalcalculusinpostmenopausalwomen.JPeriodontol.2007;78(11):2104-11.120. KosugiK,YonezuH,KawashimaS,HondaK,AraiY,ShibaharaT.Alongitudinalstudyofthe effect of experimental osteoporosis on bone trabecular structure in the rat mandibularcondyle.Cranio.2013;31(2):140-50.121. KurodaS,MukohyamaH,KondoH,AokiK,OhyaK,OhyamaT,etal.Bonemineraldensityof themandible in ovariectomized rats: analyses using dual energy X-ray absorptiometry andperipheralquantitativecomputedtomography.OralDis.2003;9(1):24-8.122. TanakaM,Ejiri S,ToyookaE,KohnoS,OzawaH.Effectsofovariectomyon trabecularstructuresofratalveolarbone.Journalofperiodontalresearch.2002;37(2):161-5.

137

123. DaiQG,ZhangP,WuYQ,MaXH,PangJ,JiangLY,etal.Ovariectomyinducesosteoporosisinthemaxillaryalveolarbone:aninvivomicro-CTandhistomorphometricanalysisinrats.OralDis.2014;20(5):514-20.124. Dvorak G, Reich KM, Tangl S, Goldhahn J, Haas R, Gruber R. Cortical porosity of themandibleinanosteoporoticsheepmodel.ClinOralImplantsRes.2011;22(5):500-5.125. RawlinsonSC,BoydeA,DavisGR,HowellPG,HughesFJ,KingsmillVJ.Ovariectomyvs.hypofunction:theireffectsonratmandibularbone.JDentRes.2009;88(7):615-20.126. HiraiT,IshijimaT,HashikawaY,YajimaT.Osteoporosisandreductionofresidualridgeinedentulouspatients.TheJournalofprostheticdentistry.1993;69(1):49-56.127. SinghalS,ChandP,SinghBP,SinghSV,RaoJ,ShankarR,etal.Theeffectofosteoporosisonresidualridgeresorptionandmasticatoryperformanceindenturewearers.Gerodontology.2012;29(2):e1059-66.128. GrazianiF,RosiniS,CeiS,LaFerlaF,GabrieleM.Theeffectsofsystemicalendronatewithorwithout intraalveolar collagen spongesonpostextractivebone resorption: a singlemaskedrandomizedclinicaltrial.TheJournalofcraniofacialsurgery.2008;19(4):1061-6.129. Ozola B, Slaidina A, Laurina L, Soboleva U, Lejnieks A. The influence of bonemineraldensityandbodymassindexonresorptionofedentulousjaws.Stomatologija.2011;13(1):19-24.130. EldersPJM,HabetsLLMH,NetelenbosJC,VanderlindenLWJ,VandersteltPF.TheRelationbetween Periodontitis and Systemic BoneMass inWomenbetween 46 and 55 Years of Age.JournalofClinicalPeriodontology.1992;19(7):492-6.131. Springe B, Slaidina A, Soboleva U, Lejnieks A. Bone mineral density and mandibularresidualridgeresorption.IntJProsthodont.2014;27(3):270-6.132. Erdogan O, Incki KK, Benlidayi ME, Seydaoglu G, Kelekci S. Dental and radiographicfindings as predictors of osteoporosis in postmenopausal women. Geriatrics & gerontologyinternational.2009;9(2):155-64.133. Drozdzowska B, PluskiewiczW, Tarnawska B. Panoramic-based mandibular indices inrelationtomandibularbonemineraldensityandskeletalstatusassessedbydualenergyX-rayabsorptiometryandquantitativeultrasound.Dentomaxillofacialradiology.2002;31(6):361-7.134. JonassonG,BankvallG,KiliaridisS.Estimationofskeletalbonemineraldensitybymeansofthetrabecularpatternofthealveolarbone,itsinterdentalthickness,andthebonemassofthemandible. Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics.2001;92(3):346-52.135. MakkerA,SinghMM,MishraG,SinghBP,JainGK,JadhavS.Relationshipbetweenboneturnover biomarkers, mandibular bone mineral density, and systemic skeletal bone mineraldensityinpremenopausalandpostmenopausalIndianwomen.Menopause.2012;19(6):642-9.136. TakaishiY,OkamotoY, IkeoT,MoriiH,TakedaM,HideK,etal.Correlationsbetweenperiodontitis and loss of mandibular bone in relation to systemic bone changes inpostmenopausalJapanesewomen.Osteoporosisinternational:ajournalestablishedasresultofcooperationbetweentheEuropeanFoundationforOsteoporosisandtheNationalOsteoporosisFoundationoftheUSA.2005;16(12):1875-82.137. VishwanathSB,KumarV,KumarS,ShashikumarP,ShashikumarY,PatelPV.Correlationofperiodontalstatusandbonemineraldensityinpostmenopausalwomen:adigitalradiographicandquantitativeultrasoundstudy.IndianJournalofDentalResearch.2011;22(2):270-6.

138

138. Horner K, Devlin H, Alsop CW, Hodgkinson IM, Adams JE. Mandibular bone mineraldensity as a predictor of skeletal osteoporosis. The British journal of radiology.1996;69(827):1019-25.139. Esfahanizadeh N, Davaie S, Rokn AR, Daneshparvar HR, Bayat N, Khondi N, et al.CorrelationbetweenbonemineraldensityofjawsandskeletalsitesinanIranianpopulationusingdualX-rayenergyabsorptiometry.DentResJ(Isfahan).2013;10(4):460-6.140. JonassonG.Bonemassandtrabecularpatterninthemandibleasanindicatorofskeletalosteopenia:a10-yearfollow-upstudy.Oralsurgery,oralmedicine,oralpathology,oralradiology,andendodontics.2009;108(2):284-91.141. HolahanCM,WiensJL,WeaverA,AssadD,KokaS.Relationshipbetweensystemicbonemineral density and local bonequality as effectorsofdental implant survival. Clinical implantdentistryandrelatedresearch.2011;13(1):29-33.142. KingsmillVJ,BoydeA.Mineralizationdensityandapparentdensityofboneincranialandpostcranialsitesintheaginghuman.Osteoporosisinternational:ajournalestablishedasresultof cooperation between the European Foundation for Osteoporosis and the NationalOsteoporosisFoundationoftheUSA.1999;9(3):260-8.143. GulsahiA,PaksoyCS,OzdenS,KucukNO,CebeciAR,GencY.Assessmentofbonemineraldensity in the jaws and its relationship to radiomorphometric indices. Dento maxillo facialradiology.2010;39(5):284-9.144. MohajeryM,BrooksSL.Oralradiographsinthedetectionofearlysignsofosteoporosis.Oralsurgery,oralmedicine,andoralpathology.1992;73(1):112-7.145. HornerK,KarayianniK,MitseaA,BerkasL,MastorisM,JacobsR,etal.Themandibularcortexonradiographsasatoolforosteoporosisriskassessment:theOSTEODENTProject.Journalofclinicaldensitometry:theofficialjournaloftheInternationalSocietyforClinicalDensitometry.2007;10(2):138-46.146. DevlinH,HornerK.Mandibularradiomorphometricindicesinthediagnosisofreducedskeletal bone mineral density. Osteoporosis international : a journal established as result ofcooperationbetweentheEuropeanFoundationforOsteoporosisandtheNationalOsteoporosisFoundationoftheUSA.2002;13(5):373-8.147. HornerK,DevlinH,HarveyL.Detectingpatientswithlowskeletalbonemass.JournalofDentistry.2002;30(4):171-5.148. DevlinH, Karayianni K,MitseaA, Jacobs R, LindhC, van der Stelt P, et al. Diagnosingosteoporosisbyusingdentalpanoramicradiographs:theOSTEODENTproject.Oralsurgery,oralmedicine,oralpathology,oralradiology,andendodontics.2007;104(6):821-8.149. Devlin H, Allen PD, Graham J, Jacobs R, Karayianni K, Lindh C, et al. Automatedosteoporosisriskassessmentbydentists:anewpathwaytodiagnosis.Bone.2007;40(4):835-42.150. Al-DamA,BlakeF,AtacA,AmlingM,BlessmannM,AssafA,etal.Mandibularcorticalshape index in non-standardised panoramic radiographs for identifying patients withosteoporosisasdefinedbytheGermanOsteologyOrganization.Journalofcranio-maxillo-facialsurgery:officialpublicationoftheEuropeanAssociationforCranio-Maxillo-FacialSurgery.2013.151. HornerK,DevlinH.Therelationshipsbetweentwo indicesofmandibularbonequalityand bone mineral density measured by dual energy X-ray absorptiometry. DentomaxillofacRadiol.1998;27(1):17-21.

139

152. BensonBW,PrihodaTJ,GlassBJ.Variationsinadultcorticalbonemassasmeasuredbyapanoramicmandibularindex.OralSurgOralMedOralPathol.1991;71(3):349-56.153. Ledgerton D, Horner K, Devlin H, Worthington H. Panoramic mandibular index as aradiomorphometrictool:anassessmentofprecision.DentomaxillofacRadiol.1997;26(2):95-100.154. BrasJ,vanOoijCP,Abraham-InpijnL,KusenGJ,WilminkJM.Radiographicinterpretationofthemandibularangularcortex:Adiagnostictoolinmetabolicboneloss.PartI.Normalstate.OralSurgOralMedOralPathol.1982;53(5):541-5.155. OrtmanLF,HausmannE,DunfordRG.Skeletalosteopeniaandresidualridgeresorption.JProsthetDent.1989;61(3):321-5.156. KlemettiE,KolmakovS,KrogerH.Pantomographyinassessmentoftheosteoporosisriskgroup.ScandJDentRes.1994;102(1):68-72.157. DevlinH, Karayianni K,MitseaA, Jacobs R, LindhC, van der Stelt P, et al. Diagnosingosteoporosisbyusingdentalpanoramicradiographs:theOSTEODENTproject.OralSurgOralMedOralPatholOralRadiolEndod.2007;104(6):821-8.158. KavithaMS,AnSY,AnCH,HuhKH,YiWJ,HeoMS,etal.TextureanalysisofmandibularcorticalboneondigitaldentalpanoramicradiographsforthediagnosisofosteoporosisinKoreanwomen.OralSurgOralMedOralPatholOralRadiol.2015;119(3):346-56.159. MarandiS,BagherpourA,ImanimoghaddamM,HatefM,HaghighiA.Panoramic-basedmandibularindicesandbonemineraldensityoffemoralneckandlumbarvertebraeinwomen.JDent(Tehran).2010;7(2):98-106.160. Carmo JZB, Medeiros SF. Mandibular Inferior Cortex Erosion on Dental PanoramicRadiographasaSignofLowBoneMineralDensityinPostmenopausalWomen.RevBrasGinecolObstet.2017;39(12):663-9.161. BaltoKA,GomaaMM,FeteihRM,AlAmoudiNM,ElsamanoudyAZ,HassanienMA,etal.DentalPanoramicRadiographicIndicesasaPredictorofOsteoporosisinPostmenopausalSaudiWomen.JBoneMetab.2018;25(3):165-73.162. Papamanthos M, Varitimidis S, Dailiana Z, Kogia E, Malizos K. Computer-assistedevaluation of Mandibular Cortical Width (MCW) index as an indicator of osteoporosis.Hippokratia.2014;18(3):251-7.163. NagiR,DeviBKY,RakeshN,ReddySS,SantanaN,ShettyN.Relationshipbetweenfemurbone mineral density, body mass index and dental panoramic mandibular cortical width indiagnosisofelderlypostmenopausalwomenwithosteoporosis.JClinDiagnRes.2014;8(8):ZC36-40.164. KimOS,ShinMH,SongIH,LimIG,YoonSJ,KimOJ,etal.Digitalpanoramicradiographsare useful for diagnosis of osteoporosis in Korean postmenopausal women. Gerodontology.2016;33(2):185-92.165. CalciolariE,DonosN,ParkJC,PetrieA,MardasN.Panoramicmeasuresfororalbonemassin detecting osteoporosis: a systematic review and meta-analysis. J Dent Res. 2015;94(3Suppl):17S-27S.166. LeiteFP,RatcliffR.Modelingreactiontimeandaccuracyofmultiple-alternativedecisions.AttenPerceptPsychophys.2010;72(1):246-73.167. Al-DamA,BlakeF,AtacA,AmlingM,BlessmannM,AssafA,etal.Mandibularcorticalshape index in non-standardised panoramic radiographs for identifying patients with

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osteoporosis as defined by the German Osteology Organization. J Craniomaxillofac Surg.2013;41(7):e165-9.168. PilgramTK,HildeboltCF,DotsonM,CohenSC,HauserJF,KardarisE,etal.Relationshipsbetweenclinical attachment level and spineandhipbonemineraldensity:data fromhealthypostmenopausalwomen.JPeriodontol.2002;73(3):298-301.169. Moeintaghavi A, Pourjavad M, Dadgar S, Tabbakh NS. Evaluation of the associationbetweenperiodontalparameters,osteoporosis andosteopenia inpostmenopausalwomen. JDent(Tehran).2013;10(5):443-8.170. MarjanovicEJ,SouthernHN,CoatesP,AdamsJE,WalshT,HornerK,etal.Dopatientswithosteoporosishaveanincreasedprevalenceofperiodontaldisease?Across-sectionalstudy.OsteoporosInt.2013;24(7):1973-9.171. Soules MR, Sherman S, Parrott E, Rebar R, Santoro N, Utian W, et al. Stages ofReproductiveAgingWorkshop(STRAW).Journalofwomen'shealth&gender-basedmedicine.2001;10(9):843-8.172. CakurB,DagistanS,SahinA,HarorliA,YilmazA.Reliabilityofmandibularcorticalindexandmandibularbonemineraldensity in thedetectionofosteoporoticwomen.Dentomaxillofacialradiology.2009;38(5):255-61.173. Lopez-Lopez J, Estrugo-Devesa A, Jane-Salas E, Ayuso-Montero R, Gomez-Vaquero C.Earlydiagnosisofosteoporosisbymeansoforthopantomogramsandoralx-rays:asystematicreview.Medicinaoral,patologiaoralycirugiabucal.2011;16(7):e905-13.174. TugnaitA,ClerehughV,HirschmannPN.Radiographicequipmentandtechniquesusedingeneraldentalpractice:asurveyofgeneraldentalpractitionersinEnglandandWales.JournalofDentistry.2003;31(3):197-203.175. SteeleJ,O'SullivanI.ExecutiveSummary:AdultDentalHealthSurvey2009.2011.176. PrimaryCareDomainHaSCIC.NHSDentalStatistics.2015.177. von Wowern N. General and oral aspects of osteoporosis: a review. Clinical oralinvestigations.2001;5(2):71-82.178. ClarkeBL,KhoslaS.Physiologyofboneloss.RadiolClinNorthAm.2010;48(3):483-95.179. Devlin H,Whelton C. Canmandibular bone resorption predict hip fracture in elderlywomen?Asystematicreviewofdiagnostictestaccuracy.Gerodontology.2013.180. DevlinH,SloanP,LutherF.Alveolarboneresorption:ahistologicstudycomparingboneturnoverintheedentulousmandibleandiliaccrest.JProsthetDent.1994;71(5):478-81.181. CrabtreeN,LoveridgeN,ParkerM,RushtonN,PowerJ,BellKL,etal.Intracapsularhipfracture and the region-specific loss of cortical bone: analysis by peripheral quantitativecomputedtomography.JBoneMinerRes.2001;16(7):1318-28.182. BellKL,LoveridgeN,PowerJ,GarrahanN,MeggittBF,ReeveJ.Regionaldifferencesincorticalporosityinthefracturedfemoralneck.Bone.1999;24(1):57-64.183. Pietrokovski J, Starinsky R, Arensburg B, Kaffe I. Morphologic characteristics of bonyedentulousjaws.JProsthodont.2007;16(2):141-7.184. TallgrenA.Thecontinuingreductionoftheresidualalveolarridgesincompletedenturewearers:amixed-longitudinalstudycovering25years.1972.JProsthetDent.2003;89(5):427-35.

141

185. Seldin EB. Is there any reason to suspect that the determinants ofmandibular bonemineraldensitymightdifferfromthoseofsystemicskeletalbonemineraldensity?Menopause.2012;19(6):608-9.186. GroenJJ,MenczelJ,ShapiroS.Chronicdestructiveperiodontaldiseaseinpatientswithpresenileosteoporosis.JPeriodontol.1968;39(1):19-23.187. Kanis JA, Reginster JY. European guidance for the diagnosis and management ofosteoporosisinpostmenopausalwomen--whatisthecurrentmessageforclinicalpractice?PolArchMedWewn.2008;118(10):538-40.188. LockerD,SladeGD,MurrayH.Epidemiologyofperiodontaldiseaseamongolderadults:areview.Periodontol2000.1998;16:16-33.189. Grocholewicz K, Bohatyrewicz A. Oral health and bone mineral density inpostmenopausalwomen.ArchOralBiol.2012;57(3):245-51.190. GoyalL,GoyalT,GuptaND.OsteoporosisandPeriodontitisinPostmenopausalWomen:ASystematicReview.JMidlifeHealth.2017;8(4):151-8.191. HiguchiT,SogaY,MuroM,KajizonoM,KitamuraY,SendoT,etal.Replacingzoledronicacidwithdenosumabisariskfactorfordevelopingosteonecrosisofthejaw.OralSurgOralMedOralPatholOralRadiol.2018;125(6):547-51.192. ReidMC,ShengeliaR,ParkerSJ.PharmacologicManagementofOsteoarthritis-RelatedPaininOlderAdults:AReviewShowsthatManyDrugTherapiesProvideSmall-to-ModestPainRelief.HSSJ.2012;8(2):159-64.193. Sigua-Rodriguez EA, da Costa Ribeiro R, de Brito AC, Alvarez-PinzonN, deAlbergaria-Barbosa JR. Bisphosphonate-relatedosteonecrosis of the jaw: a reviewof the literature. Int JDent.2014;2014:192320.194. Palomo L, Buencamino-Francisco MC, Carey JJ, Sivanandy M, Thacker H. Is long-termbisphosphonates therapy associated with benefits to the periodontium in postemenopausalwomen?Menopause.2011;18(2):164-70.

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RINGRAZIAMENTI

Moltesonostatelepersonechehannopartecipatoallarealizzazionediquestolavoroe,piùingenerale,chehannocontribuitoallamiacrescitaumanaeprofessionaledurantequestitreannidilavoro.IlprimosentitoringraziamentovaalmiotutoreeresponsabileProf.GiovanniPasseri,unaguidaespertachemihaaccompagnatoeinstradatodurantelarealizzazionedelprogettodi ricerca come anche della stesura della tesi. La possibilità di realizzare un lavoro diquesta portata, con i mezzi tecnici e umani a disposizione, è certamente legata allagenerositàealladisponibilitàchehasempremessoafavoredellacausa,edèancheperquesto che in questi anni il rapporto non si è limitato ad una mera collaborazionelavorativa.InsecondoluogoungrazievaalDirettoredelCentrodiOdontoiatria,Prof.GuidoMariaMacaluso, non un tutore ufficiale ma certamente un mentore che ha sempre datosostegnoallamiaattivitàclinicaedi ricercamediandocon intelligenza tracontrolloecollaborazionelasciandomisemprequelladosedilibertàeindipendenzanecessariaipiùgiovanipercrescere.Unruolofondamentalenellagestionedellamiaattivitàdiricercal’hannoavutaidirettoridirepartodelCentrodiOdontoiatria,Prof.SimoneLumettieProf.EdoardoManfrediperlafiduciacheognigiornomidannogarantendomilalibertàdigestireleattivitànecessariaadunaclinicaeunaricercadisuccessoeperquestoliringrazio.Insiemealoroungranderingraziamento va al Prof. Matteo Goldoni per l’indispensabile supportonell’interpretazionedell’analisistatistica.RingrazioinoltreperladisponibilitàelapazienzailpersonaletecnicoamministrativodelCentroOsteoporosiedelCentroUniversitariodiOdontoiatria:Dr.ssaGraiani,Alessandra,Annalisa,Celesta,Chiara,Deborah,Francesca,Romina,StefaniaeTina.Un ringraziamento va ai colleghi del Centro Universitario di Odontoiatria Alberto,Beatrice, Francesco e Lorenzo che mi hanno aiutato a superare i momenti difficiliriuscendoaportareunpo’dileggerezzainunambienteavolteosticodagestire.DesideroringraziareancheglistudentidelcorsodilaureaEliana,FernandoeAndreachehannopartecipatoattivamenteall’attivitàclinicalegataalprogetto.Unpensieroapartevaall’amicoecollegaDr.AndreaToffoli,avoltespallaavoltesparringpartner.Lasuapresenzacostantecomecompagnodiufficio,diavventureedisventureèstata,edètuttorafondamentale,percontinuareacrescereamigliorarecomeclinicoecomeamico.NonpossoinfinenoncitarelaDr.ssaLudovicaParisi,inseparabilecompagna

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diviaggionellenostreavventureinternazionali,èstataunsupportosemprepresenteinquestiannididuravitaalCentro.Terminati i ringraziamenti di natura professionale desidero spendere poche righeperringraziarelamiafamiglia.MiopadreMarioemiamadreElena,aiqualièdedicatoquestomanoscrittodicograzieperl’impagabilesupportoepazienza.Cometuttiifiglinonsaròmairiconoscenteasufficienzapertuttoquellocheavetefatto,fateefaretepermemasperodirendervifierisempredipiùognigiornochepassaesappiatechecercodifaredelmiomeglio.RingrazioanchemiofratelloRiccardochemihadatol’insegnamentopiùgrande che una persona possa dare, non arrendersi mai e prendere il meglio dallesituazioni.Seilapersonapiùfortecheconosco.Comespessofaccioholasciatoilmeglioallafine.IlringraziamentopiùgrandevaallamiafidanzataElena,mihaiinsegnatopiùdiquellocheunapersonacomemepossaimpararecredendoinmeanchequandoiostessoavevodeidubbi.Lastimacheelafiduciachemiinfondiognigiornomentrecondividiamolevicissitudinidellavitaedellavoromidannola spintaa cercarediessere sempremigliore. Sappi che senzadi te tuttoquestononsarebbe potuto realizzarsi, e sei l’artefice di ciò che di buono sono diventato e delsuccessochehoavuto.

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