VOLUME 44 NUMBEP 7 JULY/AUGUST 2013499QUI NTESSENCEI NTERNATI ONALIMPLANTOLOGYA prospective noninterventional study to document implant success and survival of the Straumann Bone Level SLActive dental implant in daily dental practiceAndreas Filippi, Prof Dr1/Frank L. Higginbottom, DDS2/Thomas Lambrecht, Prof Dr Dr3/Barry P. Levin, DMD4/Josef L. Meier, Dr med Dr med dent5/Paul S. Rosen, DMD, MS, PC6/Beat Wallkamm, Dr med dent7/Christoph Will, Dr med Dr med dent8/Mario Roccuzzo, DDS9Objectives: Clinical studies to assess dental implants are common in implantology, but such studies are usually performed for specic indications and following a specic proto-ool witn striot inolusion and oxolusion oritoria. Tno aim o tno ourront study was to ovaluato tno Straumann Bono Lovol SLAotivo dontal implant in a prospootivo, multioontor, nonintor-vontional trial. Method and Materials: Tno implant oould bo usod in wnatovor mannor was doomod suitablo by tno olinioian, witnin approvod indioations. No partioular plaoomont or loading protoool was spooihod. A total o 1,532 implants woro plaood in 852 pationts in 123 oontors in nino oountrios in tno US and Europo. Ator oxolusion o tnroo oountrios duo to pationt onrollmont and data issuos, 759 pationts witn 1,355 implants woro analyzod. Results: Most pationts roooivod ono or two implants (58.6% and 25.3% o pationts, rospootivoly), and 90% o oasos woro porormod witn a raisod hap. A submorgod noaling protoool was signihoantly moro provalont in Europoan oontors, wnilo transmuoosal noaling was signihoantly moro provalont in Nortn Amorioan oontors. Ator 1 yoar, 538 pationts witn 908 implants woro availablo or ovaluation. Tno oumulativo implant survival and suoooss ratos woro 98.5% and 96.0%, rospootivoly. Conclusions: Tnis prospootivo nonintorvon-tional study ovaluatod tno uso o Straumann Bono Lovol SLAotivo dontal implants in a largo numbor o pationts. Tno oumulativo survival and suoooss ratos woro similar to tnoso obsorvod in oontrollod olinioal trials, oonhrming tnis dontal implant's olinioal applioability in daily practice. (Quintessence Int 2013;44:499512; doi: 10.3290/j.qi.a29611)Key words: bono lovol dontal implant, daily dontal praotioo, nonintorvontional study, SLAotivo1Department of Oral Surgery, Oral Radiology and Oral Medicine, SchoolofDentalMedicine,UniversityofBasel,Basel,Switzer-land.2Professor,RestorativeSciencesandGraduateProsthodontics, Dallas, TX, USA.3Department of Oral Surgery, Oral Radiology and Oral Medicine, SchoolofDentalMedicine,UniversityofBasel,Basel,Switzer-land.4Clinical Associate Professor, University of Pennsylvania, Depart-mentofGraduatePeriodontology;andPrivatePractice,Elkins Park, PA, USA.5PrivatePracticeandIn-patientDoctor;SpecialistinOraland MaxillofacialSurgery;MKG-LandshutPraxisklinikfrMKG-Chirurgie,ImplantologieundParodontologie,Landshut,Ger-many.6ClinicalAssociateProfessorofPeriodontics,BaltimoreCollege of Dental Surgery, University of Maryland Dental School, Balti-more, MD, USA; and Private Practice, Yardley, PA, USA.7SpecialistinPeriodontologySSO,ClinicalAssociateProfessor, University of Berne, Department of Periodontology; and Private Practice, Langenthal, Switzerland.8PrivatePractice;SpecialistinOralandMaxillofacialSurgery; Zentrum fr zahnrztliche Chirurgie Implantologie, Kitzingen, Germany.9PrivatePractice,Torino,Italy;andLecturerinPeriodontology, University of Siena, Italy.Correspondence:DrMarioRoccuzzo,CorsoTassoni14,10143 Torino, Italy. Email: mroccuzzo@iol.it.Endossoousdontalimplantsnavodomon-stratodoxoollontlong-tormsurvivaland predictablesupportfordentalprostheses, fromsinglecrownstofull-archxeddental prostnososandovordonturos.1-6Tnosuo-cess of dental implants in patients has been oxtonsivolydomonstratodinolinioaltrials orovor20yoars.Suonolinioalstudiosto assossdontalimplantsurvivalratosaro commoninimplantology,andtheresults areoftencitedbydentalimplantmanufac-500 VOLUME 44 NUMBEP 7 JULY/AUGUST 2013QUI NTESSENCEI NTERNATI ONALFi l i ppi et alturers as proof of the success of their prod-ucts.7,8Howovor,tnosostudiosarousually performedaccordingtoaprotocolwith strict inclusion and exclusion criteria, which dictates the enrollment of patients with spe-oihodontalsituations,oraimtoinvostigato a specic indication. One potential criticism ofsuchstudies,therefore,isthattheymay notaoouratolyrohoottnowidovariotyo patients and situations seen in normal daily dontalpraotioo.Tnoolinioiansinvolvodin suchformalclinicaltrialsmaypotentially dovotomorotimoandattontiontotno patients in the trial, due to the study set-up. naddition,tnoolinioiansinvolvodintnoso olinioal trials aro usually spooialists or navo additional training in a particular dental dis-cipline, and this may increase the likelihood onignorimplantsurvival.9Fortheserea-sons,formalclinicaltrialsmaybebiased towards moro avorablo outoomos.10Tominimizosomootnooritioismslov-iedastotheapplicabilityofahighlycon-trolledinstitution-basedstudytoclinical privatopraotioo,anonintorvontionalstudy couldbedesignedandinitiatedforthe ovaluation o a partioular modioal dovioo. n anonintorvontionaltrial,tnoproduotin questionwouldbeusedinthemannerfor wnion it nas boon approvod, but tno assign-mentofpatientstoaparticulartherapeutic strategywouldnotbedeterminedbya clinicaltrialprotocol.Instead,treatmentis determinedaccordingtothestandardcur-rent practice of the clinician, independent of thedecisiontoincludethepatientinthe study.Howovor,tnousagootnoproduot wouldbesystematicallydocumentedand analyzod.Tnointontionosuonanonintor-vontionalstudyintnooontoxtodontal implantologywouldtnoroorovoriytno resultsofcontrolledclinicalstudiesina real-world situation.mplant outoomos aro inhuonood by tno implantdesignaswellasthesurgicalpro-ooduro.Tnoroisawidovariotyoimplant designsandsurfacesonthemarket,with anemphasisinrecentyearsonimplants andsurgicalproceduresdesignedfor improvodostnotiorosults.11,12Estheticout-comesdependmainlyontheamountof peri-implantboneremodeling,whichcan boinhuonoodbytnoimplantdosign.13Fol-lowingimplantplacement,thegoalwith estheticimplanttreatmentisthereforeto minimizo bono loss as muon as possiblo.14A bono lovol implant witn a sand-blastod, large-grit, acid-etched, and hydrophilic sur-aoo (SLAotivo) nas boon dovolopod witn a viowtoobtainingmoroprodiotabloout-oomos in tno ostnotio zono. Tno Straumann BonoLovolimplantisdosignodtobo placedwiththeneckoftheimplantatthe samolovolastnoorostalbono.Unlikosot tissuo lovol implants, tno bono lovol implant hasnometallictulip-shapedshoulder,so tnat tno visibility o any gray motallio snadow throughthesofttissuecanbeeliminated. Proolinioalstudiosovaluatingtnoplatorm switoningoonooptwitntnisimplantnavo snownvorylittlobonolossandnosignih-cantdifferencesbetweensubmucosaland transmucosalhealingapproaches.15Tno rosultsworoinlinowitntnosoobsorvodin similar provious studios,16,17 but with smaller orostal bono loss valuos, moan bono loss 6 montnsatorloadingwas+0.17 mm, -1.32 mm,and-0.15 mmorsubmuoosal implantsplaoodabovo,bolow,orattno orostalbonolovol,rospootivoly,and -0.20 mm,-1.40 mmand-0.47 mmor transmuoosalimplantsplaoodabovo, bolow, and at tno orostal bono lovol, rospoo-tivoly.Asooondstudywitnasimilarproto-colshowedbone-to-implantcontactper-oontagos6montnsatorloadingo71.5%, 71.8%, and 73.3% or submuoosal implants abovo,bolow,andattnobonoorostlovol, and 76.0%, 74.5%, and 73.2% or transmu-oosalimplantsabovo,bolow,andattno bono orost lovol, rospootivoly.18Tno goal o tno prosont study was to ovalu-atotnosuooossandsurvivaloStraumann BonoLovolSLAotivoimplantsindailydontal practice in normal clinical situations for up to 3 yoars, 1-yoar rosults aro roportod noro.METHOD AND MATERIALSClinicians, patients, and implantsTnisstudywasaprospootivo,multioontor, nonintorvontionalstudyusingStraumann BonoLovolSLAotivoimplants(nstitut Straumann).Tnoimplantsworoallowodto bo usod in all approvod indioations and all implanttherapiesatthediscretionofeach VOLUME 44 NUMBEP 7 JULY/AUGUST 2013501QUI NTESSENCEI NTERNATI ONALFi l i ppi et alindividual olinioian. Clinioians woro allowod to tako part in tno study providod tnat tnoy weregenerallyfamiliarwithandlegally allowedtoperformdentalimplanttreat-mont.Tnooxporionooandoduoational backgroundofparticipatingclinicianswas assessedbyinternet-basedbackground searches.Patientswereeligibletopartici-pateiftheirgeneralmedicalconditionwas sufcienttoallowanoralsurgicalproced-ureandifdentalimplanttreatmentwas indioatodortootnrostoration.Nospooiho inclusion or exclusion criteria were applied, and there was no general medical condition where oral surgical procedures were contra-indicated.Patientwillingnesstoconsentto participationinthestudywasnecessary, anddatacollectionandanalysiswere dosignodtoprosorvotnoanonymityotno pationts. All aspoots o tno study woro por-formedaccordingtotheWorldMedical AssooiationDoolarationoHolsinki'or pationts partioipating in olinioal studios. Tno studynasboonindopondontlyroviowod andapprovodbytnorospootivootnios committeesofeachparticipatingcountry, where applicable.Tnoimplants(BonoLovolSLAotivo, nstitut Straumann) nad a body diamotor o 4.1 mm and longtns o 8, 10, 12, or 14 mm. Avariotyoabutmontsworoallowodtobo usod, inoluding provisional abutmonts, solid abutments,Mesoabutments,anatomic abutments,goldabutments,andLocator abutmonts. All prostnotio oompononts woro to be used within their standard indications androoommondationsoruso.Nopartiou-larimplantplacementorloadingprotocol wasspooihod,allsurgioalprotooolsrom immediateimplantplacementinextraction sookots to plaoomont in sitos noalod or 16 wooks and ovor woro allowod, and all load-ingprotooolsromimmodiato(witnin48 noursatorplaoomont)todolayod(> 6 montnsatorplaoomont)woroallowod,at thediscretionofeachparticipatingclini-oian. All implants woro to bo plaood aooord-ingtonormaltreatmentprotocolsandthe manuaoturor's rooommondations.Surgical procedures and assessmentsPatientexaminationwasperformedata prosurgory visit, and inormod oonsont was obtainod. Domograpnio data (ago, sox, and raoo),oralnygionosooro(basodontno invostigator's olinioal oxporionoo |1 = oxool-lont,2 = good,3 = satisaotory,4 = bad]), dontalsituation(numborandpositiono missingtootn),androasonsortootnloss wororooordod.Pationtsworoalsoovalu-atodordontal/oralriskaotors(untroatod periodontitis, insufcient oral hygiene, brux-ism,andnorizontal/vortioalbonodooots) andsystomioriskaotors(smoking,mota-bolic diseases, medication, alcohol or drug abuse, radiotherapy, tumor surgery, chronic sinusitis, and pnysioal disability).Typos and sitos o implants plaood woro dooumontodatimplantplaoomont(hrst stago surgory), and tno typo o noaling pro-ooduro(submorgod,nonsubmorgod,or somi-submorgod)andabutmont/noaling abutmontusodwasrooordod.Tnotimo sincethetoothtobereplacedwaslostor romovodwasrooordodandoatogorizod aooordingtotnoProooodingsotnoT Consensus Conference:19typo 1: immodiato plaoomont as part o the same surgical proceduretypo2:oarlyplaoomontwitnsottissuo noaling (4 to 8 wooks)typo 3: oarly plaoomont witn partial bono noaling (12 to 16 wooks)type 4: late placement in fully healed site (. 6 montns).Implant loadingntnoovontosooond-stagosurgory(or submorgodimplants),tnotypoosooond-ary component and any complications were recorded.Loadingprotocolsfollowedthe normaltimeschedulesfollowedineach center.Implantswereloadedwithsingle crowns,splintedcrowns,orxedpartial dentures, or full- or partial-arch prostheses. For temporary and nal restoration, the type ofrestorationwasrecorded,implantsuc-oossandsurvivaloritoriaworoovaluatod, oomplioationsworonotod,andsub|ootivo radiograpniobonolovoloxaminationwas performed. Implant loading was performed aooording to tno individual pationt situation, and tno loading protoools woro oatogorizod according to the criteria by Cochran et al20:Immediaterestoration:restoration plaoodoutoooolusionwitnin48nours of implant surgery502 VOLUME 44 NUMBEP 7 JULY/AUGUST 2013QUI NTESSENCEI NTERNATI ONALFi l i ppi et alImmediate loading: restoration placed in ooolusion witnin 48 nours o implant sur-geryEarly loading: restoration placed at least 48 nours ator implant surgory, but witnin 3 montnsConvontional loading: rostoration plaood inasecondprocedureafterahealing poriodo3to6montnsatorimplant surgeryDolayod loading: rostoration plaood in a sooondproooduroatloast6montns after implant surgery.Follow-up evaluationsFollow-up ovaluations, oxamining poriapioal radiograpny, implant suoooss and survival, radiograpnio bono lovol moasuromont, and oomplioations, woro porormod ator 1 yoar, witnurtnorollow-upvisitsplannodator2 and 3 yoars. Padiograpny and radiograpnio moasuromontobonolovolworostrongly rooommondod,wnoroporormod,tnoso woro not standardizod tnrougnout tno study, butwereperformedaccordingtoeach olinio's standard proooduro.Implant success was dened according to tno oritoria by Busor ot al21:absence of painabsence of recurrent peri-implant infectionabsence of tactile mobilityabsence of continuous peri-implant radio-lucency.Surviving implants woro tnoso tnat woro still in place, whether functionally successful or not.Implantfailurewasdenedbyimplant romoval, raoturo boyond ropair, or olassih-oation otnor tnan suooossul or surviving.EndpointsTnoprimaryondpointsworotnoimplant survivalandsuooossratos1yoarator abutmont plaoomont. Sooondary ondpoints woroonangoinorostalbonolovoland ovaluationoloadingprotoool.Dosoriptivo statistios(moansandstandarddoviations) worousodtoroporttnodata.Toovaluato anypotontialdioronoosbotwoontnoUS and Europoan pationt groups, a Studont's t testwithatwo-taileddistributionandtwo-samplo unoqual varianoo was porormod, P valuos loss tnan .05 woro oonsidorod statis-tically signicant.RESULTSPatients, clinicians,and implantsPationtsworoonrollodat123oontorsin nino oountrios (Bolgium, Canada, Gormany, taly,TnoNotnorlands,Spain,Switzorland, Unitod Kingdom, and tno Unitod Statos). A total o 852 pationts roooivod 1,532 implants (Fig 1).Tnomoanpationtagowas 53.7 15.0yoars(rango16.3to88.8 yoars), 55.6% woro womon and 44.2% woro mon (data woro missing or 0.1%). Tno roa-sons or tootn loss aro dotailod in Tablo 1.Atotalo102olinioianstookpartintno study,oaonplaoing13.3implantsonavor-ago(rango,1to76implants,modo,10 implants).Tnooduoationalbaokgroundo theparticipatingcliniciansispresentedin Fig 2.Fity-twoolinioiansworoidontihodas oralandmaxilloaoialsurgoons,6woro periodontists,and44wereclassiedas general dentists. In addition to the academic oduoation it was also ovaluatod tnat 19 olini-cians were specialists in oral implantology. Upon analyzing tno rosults, it was appar-onttnatsovoralproblomsworoonooun-tered in centers from three of the countries (Bolgium,TnoNotnorlands,andSpain). Duototnoinoomplotorooordingodata (og, only 32 o a total o 90 pationts in tnoso countrieshadadocumentednalrestora-tion)andinoonsistontollow-upanalysos (only11/90pationtsworoavailabloattno 1-yoar ollow-up), data analysis was inoom-plotoortnosooountrios.Tnus,itwas decided to exclude these countries from the analysis.Intheremainingsixcountries,a total o 759 pationts roooivod 1,355 implants (Fig 1),tnomoanpationtagowas 54.2 15.0yoars(rango18.0to88.8 yoars). Tnis pationt population was usod or all subsequent results.Nodontalorsystomioriskaotorsworo roportodor60.9%and84.6%opationts, rospootivoly. Tno most oommon dontal risk aotor was norizontal or vortioal bono dooot (20.9%opationts),ollowodbybruxism (6.9%), and insuhoiont oral nygiono or pori-odontitis(1.7%oaon).Tnomainsystomio riskfactorwastheuseofconcomitant modioation(2.8%),ollowodbydiabotos mollitus and ostooporosis (1.1% oaon). Tno provalonooootnorriskaotors(motabolio VOLUME 44 NUMBEP 7 JULY/AUGUST 2013503QUI NTESSENCEI NTERNATI ONALFi l i ppi et alTable 1Reasons for tooth loss: the reason for tooth loss was recorded for all patients enrolled in the studyReason No. of implants (%)Periodontitis 519 (33.9%)Caries 347 (22.7%)Unsuccessful endodontic treatment 200 (13.1%)Tootn raoturo 174 (11.4%)Loss due to trauma 75 (4.9%)Congenitally missing 68 (4.4%)Exoossivo intornal root rosorption 13 (0.8%)Provious implant lost 12 (0.8%)Poot rosorption ollowing ro-implantation 3 (0.2%)Fraoturo o provious implant 1 (0.1%)Other 120 (7.8%)Total 1,532 (100%)1-year follow-up:538 patients, 908 implantsFinal restoration: 643 patients, 1,113 implants1 implant failure,3 of unknown statusProvisional restoration:653 patients, 1,134 implants1 implant failureImplantation:759 patients, 1,355 implants9 implant failuresEnrollment:852 patients, 1,532 implantsBelgium, Netherlands, Spain excluded from analysisFig 1Number of patients and implants. The number of patients and implants are depicted from the patient enrollment until the 1-year follow-up: 759 patients received a total number of 1,355 implants at the implanta-tionvisit.After1year,538patientsand908implantswerestillincludedinthestudy.Theimplantfailures between the visits are presented. In total, 11 implants failed during the rst year after placement and 3 were of unknown status.6%Periodontists51%Oral and maxillofacial surgeons43%General dentistsFig2Educationalbackgroundofthe102partici-patingclinicians.Amongthe102participatingclin-icians from 6 countries, the academic education was evaluated by internet-based background checks; 52 wereidentiedasoralandmaxillofacialsurgeons based on reported comprehensive education in this eld, 6 were periodontists, and 44 were classied as general dentists. Clinicians were classied as general dentistsifnotreportedotherwise.Besidestheaca-demicbackground,19clinicianscouldbeclassied as specialists in dental implantology due to reported education.504 VOLUME 44 NUMBEP 7 JULY/AUGUST 2013QUI NTESSENCEI NTERNATI ONALFi l i ppi et aldisease other than diabetes mellitus, tumor surgory and/or radiation tnorapy, and pnys-ioal disability) was lowor tnan 1% oaon. Tno ma|orityopationtssnowodgood(59.4%) or satisaotory (26.0%) oral nygiono sooros, witnoxoollontsoorosin12.5%,only1.8% snowodabadoralnygionosooro.Tno ma|orityotnopationts(87.6%)woronon-smokers. Mostpationtsroooivodonoortwo implants(58.6%and25.3%opationts, rospootivoly), wnilo 5.4% and 5.3% roooivod tnrooandourimplants,rospootivoly.Tno romainingpationtsroooivodbotwoonhvo and oignt implants (2.0%, 2.4%, 0.5%, and 0.5% or hvo, six, sovon, and oignt implants, rospootivoly). mplant longtns o 12 mm and 10 mmworomostoommonlyusod(48.6% and 34.2% o implants, rospootivoly), 9.7% woro14-mmlongand7.2%woro8-mm long.ntotal,70.8%otnoimplantsworo plaoodintnomaxillaand29.2%woro plaood in tno mandiblo. Tno dotailod implant distributionaccordingtothetoothposition issnowninFig 3.ntotal,649implants (47.9%)woroplaoodintnoostnotiorogion (positions14to24aooordingtoFDWorld Dontal Fodoration notation).12010080604020038 37 36 35 34 33 32 31 41 42 43 44 45 46 47 48FDI tooth position - mandibleNumber of implants12010080604020018 17 16 15 14 13 12 11 21 22 23 24 25 26 27 28FDI tooth position - maxillaNumber of implantsFig 3Implant distribution according to tooth position. The number of implants per tooth position is depict-ed in the maxilla (a) and in the mandible (b), according to the FDI World Dental Federation notation. A total of 649 implants (47.9%) were placed in the esthetic region (positions 14 to 24).baVOLUME 44 NUMBEP 7 JULY/AUGUST 2013505QUI NTESSENCEI NTERNATI ONALFi l i ppi et alTable 2Classifcation for the timing of implant placement. The time between tooth loss or extraction and implantation was categorized according to the Proceedings of the ITI Consensus Conference.19 Absolute numbers of implants and percentages (in parentheses) are shown according to region.Classifcation United States/Canada Europe OverallTypo 1: dirootly ator tootn oxtraotion(immodiato plaoomont)57* (42.9%) 128* (10.5%) 185 (13.7%)Typo 2: 48 wooks postoxtraotion(oarly plaoomont witn sot tissuo noaling)6* (4.5%) 184* (15.1%) 190 (14.0%)Typo 3: 1216 wooks postoxtraotion(oarly plaoomont witn partial bono noaling)11 (8.3%) 172 (14.1%) 183 (13.5%)Typo 4: . 16 wooks(lato plaoomont)59* (44.4%) 738* (60.4%) 797 (58.8%)Total 133 (100%) 1,222 (100%) 1,355 (100%)*Statistioally signihoant dioronoo (P < .01) botwoon tno rogions, statistioally signihoant dioronoo (P = .03) botwoon the regions.Surgical proceduresTno timo botwoon tootn loss or tootn oxtrao-tionandimplantationwasrecordedforthe 1,355insortodimplants.Tnotimingo implant plaoomont was oatogorizod as typo 1 to 4, aooording to tno Proooodings o tno TConsonsusConoronoo(Tablo 2).19 Tnoro was a dioronoo ovidont botwoon tno EuropoanandNortnAmorioanoontors.n European centers implants were preferably plaoodlatoatortootnoxtraotion(60.4% typo4,. 6montnsatortootnoxtraotion), whileonlyaminorityofimplantswere placedimmediatelyaftertoothextraction (10.5%typo1:immodiatolyatortootn oxtraotion).noontrast,inNortnAmorioan centers the majority of implants were prefer-ably plaood oitnor immodiatoly (42.9% typo 1) or lato ator tootn oxtraotion (44.4% typo 4).Tnus,tnoroworosignihoantdioronoos in the timing of implant placements between tnoEuropoanandNortnAmorioanoontors (P valuos snown in Tablo 2). Figuro 4 snows an exemplary case of a patient whose man-dibularrightrstpremolarwasextracted4 weeks prior to implant placement.Asurgioalprooodurownoroahapwas olovatodwasporormodin90%ooasos, wniloahaplossprooodurowasporormod inonly9.1%ooasos,ortnoromaining casesthesurgicalprocedurewasnot rooordod. Tno bono quality rooordod at tno position o oaon implant is snown in Tablo 3. Primary stability was aoniovod or 98.6% o implants placed.Tnonoalingprotooolusodissnownin Tablo 4.Similartotnotimingoimplant plaoomont, tnoro was a dioronoo obsorvod inthehealingprotocolbetweentheEuro-poanandNortnAmorioanoontors,Euro-peancenterspredominantlyusedasub-morgod protoool (65.8% o implants), wnilo NortnAmorioanoontorsprodominantly omployodtransmuoosalnoaling(74.8%o implants).Tnosonoalingprotooolsworo signihoantlydioront(P < .01)botwoon Europo and Nortn Amorioa. Howovor, tnoro wasnosignicantdifferenceforsemi-sub-morgod noaling (7.1% in Europoan oontors oomparod to 10.7% in Nortn Amorioan oon-tors, P = .20). Provisional and fnal restorationO1,134implantsin653pationtswnoro dataworoavailabloorovaluationattno provisionalrostorationstago,tnoroworo nino implant ailuros (Fig 1). Provisional ros-torationwasporormodor278implants (24.5%). Data rom a total o 1,113 implants in 643 pationts woro availablo or analysis at tnohnalrostorationstago(Fig 1),andono additionalimplantailurowasnotod(io,all 506 VOLUME 44 NUMBEP 7 JULY/AUGUST 2013QUI NTESSENCEI NTERNATI ONALFi l i ppi et alFig 4Exemplary clinical case. The place-ment of an implant into the extracted site of the mandibular right rst premolar and subsequentrestorationareshown.Surgi-caltreatmentwasperformed4weeks after extraction and soft tissue healing (a). Fullapelevationrevealedawidedefect aecting the adjacent teeth (b), which was treatedwithscaling,EDTA(ethylenedi-aminetetraaceticacid)andStraumann Emdogain(c)priortoimplantplacement (d).Bonegraftingusingdemineralized bovinebonemineral(e)wasperformed beforesuturingforsubmergedimplant healing (f). The clinical situation 16 weeks aftersurgerywithhealthyperi-implant softtissues(g)allowedimpressiontaking (h).Thenalceramiccrownisshownin placewithashallowprobingdepth(i), stable peri-implant soft tissues (j), and the respective radiographic image (k).ailurosnadboonproviouslyrooordodat tno provisional rostoration visit). Tno oumu-lativoimplantsurvivalratowastnorooro 99.1%attnisstago.Problomswitntno implants woro notod in 14 oasos, inoluding oignt oasos o radioluoonoy (0.7%) and our oasos o pori-implantitis (0.3%). Tablo 5snowstnotyposorostorations usedatthenalrestorationstage.Most rostorationsworooomontod(78.6%o adgjkbehcfiVOLUME 44 NUMBEP 7 JULY/AUGUST 2013507QUI NTESSENCEI NTERNATI ONALFi l i ppi et alimplants), sorow rotontion was usod in only 11.4% o oasos, and otnor typos o rotontion worousodin8.7%ooasos.Convontional implantloadingwaspredominantlyused (68.6%oimplants),ollowodbydolayod loading (14.6%), and oarly loading (12.4%) (Tablo 6). Convontional loading was signih-oantly moro provalont in tno Europoan oon-tors tnan tno Nortn Amorioan oontors (70.0% oomparodto57.5%,P = .01).mmodiato loadingandrostorationworomoroprova-lont in tno Nortn Amorioan oontors, nowovor the differences were statistically not signi-cantcomparedtotheEuropeancenters (3.3% vs 0.2% |P = .06] or immodiato load-ing and 6.7% vs 2.2% |P = .05] or immodi-ato rostoration).Implant survival and success and bone measurements after 1 yearAtor 1 yoar, a total o 538 pationts witn 908 implantsworoavailabloorovaluation (Fig 1).Attnisstago,tnorowasonoaddi-tionalimplantailurorooordod(duotoloss oossoointogration)andtnrooimplants wheredatawereunknownormissing. Takon togotnor, a total o 14 implants oitnor ailod or nad a laok o dooumontod survival Table 3Bone quality: at the implantation visit, bone quality was recorded at the position of each implantBone quality No. of implants Frequency (%)Typo 1 91 6.7Typo 2 641 47.3Typo 3 532 39.3Typo 4 79 5.8Unknown/missing 12 0.9Total 1,355 100Table 4Implant healing protocol according to region: implants were allowed to heal according to one of the three healing protocols indicatedHealing protocol United States/Canada Europe OverallSubmorgod 19* (14.5%) 806* (65.8%) 825 (60.9%)Somi-submorgod 14 (10.7%) 87 (7.1%) 101 (7.5%)Transmuoosal 98* (74.8%) 327* (26.7%) 425 (31.4%)Unknown/missing 0 (0.0%) 4 (0.3%) 4 (0.3%)Total 131 (100%) 1,224 (100%) 1,355 (100%)*Statistioally signihoant dioronoo (P < .01) botwoon tno rogions, dioronoo not statistioally signihoant (P = .20) between the regionsTable 5Type of restoration recorded at the fnal restoration visitType of restoration No. of implants Frequency (%)Singlo orown 608 54.6Fixod partial donturos (inoluding oantilovor) 358 32.1Full-arch prosthesis 105 9.4Partial-arch prosthesis 25 2.2Unknown/missing 17 1.5Total 1,113 100508 VOLUME 44 NUMBEP 7 JULY/AUGUST 2013QUI NTESSENCEI NTERNATI ONALFi l i ppi et alwithin the rst year after implant placement, rosultinginaoumulativosurvivalratoo 98.5%, basod on 908 implants ator 1 yoar. Fewproblemswiththeimplantswere notod at tno 1-yoar ollow-up, inoluding hvo oasosopori-implantitis(0.6%oimplants) andonooasooradioluoonoy(0.1%).Tno ovorallsuooossratootnobonolovol implantswascalculatedbasedonthesuc-oossoritoriaaspublisnodbyBusorotal.21 Tnorooro,ianovontsuonaspain,pori-implantitis,mobility,orradiolucencywas reported, they were counted as unsuccess-ulimplants,irrospootivoownotnortno ovont was transiont or porsistont. No distino-tion in tno porsistonoo o an ovont was mado during data aoquisition. A total o 36 oompli-oations, probloms and/or ailuros tnat appliod to the success criteria were reported within the rst year after implant placement, which rosultodinaoumulativosuooossratoo 96.0%, basod on 908 implants ator 1 yoar. Wnororadiograpniobonolovolwas ovaluatod,tnorowasnoonangoinorostal bono lovol at tno ma|ority o implants (62.2% and61.8%mosialanddistal)(Tablo 7). Cnango in bono lovol o groator tnan 1 mm wasobsorvodatlosstnan5%oimplants (4.5%and3.9%mosialanddistal),wnilo bono growtn was obsorvod in around 3% o oasos(3.3%and3.0%mosialanddistal). Duototnononintorvontionalnaturootno study, no radiographs were acquired for the remainingimplantsbecausethiswasnot partofthestandardprocedureofthe rospootivo dontal praotitionors. Table 7Crestal bone level: the number (%) of implants with mesial and distal radiographic bone level changes is indicated at the 1-year follow-upMesial DistalNo onango 565 (62.2%) 561 (61.8%)< 0.5 mm 108 (11.9%) 100 (11.0%)0.51 mm 43 (4.7%) 63 (6.9%)12 mm 32 (3.5%) 26 (2.9%)23 mm 5 (0.6%) 5 (0.6%)34 mm 4 (0.4%) 2 (0.2%)> 4 mm 0 (0%) 2 (0.2%)Bono growtn 30 (3.3%) 27 (3.0%)Not ovaluatod or unknown 121 (13.3%) 122 (13.5%)Total 908 (100%) 908 (100%)Table 6Implant loading protocol: numbers of implants and percentages (in parentheses) according to regionLoading protocol United States/Canada Europe OverallImmediate loading 4* (3.3%) 2* (0.2%) 6 (0.5%)Immediate restoration 8 (6.7%) 22 (2.2%) 30 (2.7%)Early loading 14 (11.7%) 124 (12.5%) 138 (12.4%)Convontional loading 69 (57.5%) 695 (70.0%) 764 (68.6%)Dolayod loading 21# (17.5%) 142# (14.3%) 163 (14.6%)Unknown/missing 4(3.3%) 8(0.8%) 12 (1.1%)Total 120(100%) 993(100%) 1,113 (100%)*Dioronoo not statistioally signihoant (P = .06), dioronoo not statistioally signihoant (P = .05), difference not statisti-oally signihoant (P = .80), dioronoo statistioally signihoant (P = .01), #dioronoo not statistioally signihoant (P = .38).VOLUME 44 NUMBEP 7 JULY/AUGUST 2013509QUI NTESSENCEI NTERNATI ONALFi l i ppi et alComplicationsComplicationsweredocumentedthrough-out tno ontiro study. Tno ollowing oomplioa-tionswerereportedatsecondstage surgory: ormation o hstula (3 oasos), oom-plioationswitnrogonorativoproooduros(2 oasos),andoxoossivobonorosorption(1 oaso).Atprovisionalrostoration,oomplioa-tionswitnprostnotios(8oasos),oxoossivo bonorosorption(4oasos),oomplioations witn sot tissuo managomont (3 oasos), pain (1 oaso), and implant mobility (1 oaso) woro roportod. At hnal rostoration, oomplioations witnsottissuomanagomont(4oasos), oomplioationswitnprostnotios(3oasos), ormationohstula(1oaso),andimplant mobility(1oaso)wororoportod.Finally,at tno1-yoarollow-up,tnoollowingoompli-cationswerereported:complicationswith prostnotios (3 oasos), sot tissuo inhamma-tion(2oasos),radioluoonoy(1oaso),pain (1oaso),oomplioationswitnsottissuo managomont (1 oaso), and oxoossivo bono rosorption (1 oaso).DISCUSSIONTnousoodontalimplantsortnorostora-tionofmissing,lost,orextractedteethhas become a widely accepted treatment solu-tion,andpatientdemandsintermsof estheticsandtimelyrestorationoffunction navo dramatioally inoroasod in rooont yoars. Clinioians and industry navo tnorooro triod to dovolop now toonniquos and produots to aoniovotnis,inoludingbotnnowsurgioal procedures and implant designs.Tnopurposootnislargoprospootivo multioontornonintorvontionaltrialwasto ovaluatotnoporormanoooStraumann Bono Lovol SLAotivo implants in daily olini-oaldontalpraotioo.Tnorosultsdomon-stratedtheexcellentperformanceofthese implantsinallindicatedclinicalsituations. From tno 1,355 insortod implants, a total o 11 implant ailuros woro roportod witnin tno hrst yoar o implant plaoomont, and survival wasnotdocumentedforthreeadditional implants.Tnorooro,atotalo14implant ailurosworooonsidorod.Basodontno romaining908implantstnatoouldbo assossodattno1-yoarollow-up,tnis rosultodinaoumulativosurvivalratoo 98.5%.Sinootnooumulativosurvivalrato includesallfailedorundocumentedcases outotnoinitial1,355implants,itisaoon-sorvativomoasurootnooootivosurvival rato.ntormsoimplantsuoooss,36oom-plioations,probloms,and/orailurosworo reportedthatapplytothesuccesscriteria oBusorotal21withintherstyearafter implantplacement,whichresultedina oumulativosuooossratoo96.0%.Aswitn tnooumulativosurvivalrato,tnisporoont-agoislikolytoundorostimatotnooootivo rate,becauseallreportsfromtheinitial 1,355implantsworooountodandtnon rolatodtotnoromaining908implants. Tnosoratosworooomparablowitntnoso obsorvodinormaloontrollodolinioaltrials witn moro rostriotivo pationt solootion motn-ods.Foroxamplo,1-yoarrosultsroma randomizod,oontrollodolinioalstudywitn 127StraumannBonoLovolSLAotivo implantsplaoodin127pationtswitnoitnor submergedortransmucosalhealing snowod implant survival ratos o 100% and 98.3% or tno submorgod and transmuoosal groups,rospootivoly.22Survivalandsuo-oossratoso100%woroalsooundina singlooonortstudyovaluatingStraumann Bono Lovol SLAotivo implants plaood in 20 oonsooutivo pationts in singlo tootn gaps in tno ostnotio zono ator a noaling poriod o 4 to8wooks.23Inthisstudy,successand survivalromainodunonangodupto3 years.24Tnoprosontstudyrovoalodoortaindi-ferencesinthesurgicalprotocolbetween EuropoanandNortnAmorioanstudyoon-tors,Europoanoontorsprodominantly omployodlatoimplantplaoomont(60.4%) and a submorgod noaling protoool (65.8%), wniloNortnAmorioanoontorsprodomi-nantly used either immediate or late implant plaoomont (42.9% and 44.4%, rospootivoly) incombinationwithtransmucosalhealing (74.8%).Similarly,loadingoimplantswas performeddifferentlyinthetworegions. Convontional loading was signihoantly moro provalont in tno Europoan oontors tnan tno NortnAmorioanoontors(70.0%vs57.5%), and immediate loading and restoration were signihoantlymoroprovalontintnoNortn Amorioan oontors (3.3% and 6.7% vs 0.2 % and 2.2%). Honoo, tnoro may bo tondonoy forEuropeanimplantologiststorelyona 510 VOLUME 44 NUMBEP 7 JULY/AUGUST 2013QUI NTESSENCEI NTERNATI ONALFi l i ppi et almorooonvontionalproooduro,wniloNortn Amorioan implantologists avor a moro oon-donsodproooduro.Tnomotivationortno diorontproooduroswasnotovaluatodin this study and potential clinical implications thereforeremainunclear.Unfortunately, duetotheheterogeneityofthedataasa rosult o tno nonintorvontional naturo o tno study(og,laokodohnodinolusion/oxolu-sion oritoria), it was not possiblo to pororm a differential analysis of the outcomes of the rospootivosurgioalprotooolsaooordingto rogion.Suonananalysiswouldroquiroa controlled clinical trial with all other param-otors(og,pationtdomograpnios,indioa-tions) oqualizod, and was obviously outsido the scope of the present study.Tno rosults o tno prosont study snowod thatthemajorityofimplantsshowedno onangoinorostalbonolovolupto1yoar, witn loss tnan 5% o implants snowing orostal bono loss o groator tnan 1 mm. Tnis appoars tomirrortheresultsfromarecentclinical studyin127pationtswitnStraumannBono Lovolimplantsintnoantoriormaxillaand mandible.22Similarolinioaloutoomoswitn bothsubmergedandtransmucosalhealing and a minimal mean change in crestal bone lovolo< 0.5 mm(-0.47 mmand-0.48 mm forsubmergedandtransmucosalimplants, rospootivoly)woroobsorvodovor12 months.22Moroovor,goodostnotiorosults witn tno Straumann Bono Lovol implant navo boondomonstratodinaprospootivooaso sorios oonduotod ovor a 12-montn poriod.23 Tnoso rosults romainod stablo up to 3 yoars, atwhichtimethemeanbonelosswas 0.18 mm.24Tnolimitodbonolossortno StraumannBonoLovolimplantmaybo related to its platform switch, which has been corroborated by preclinical studies compar-ingthisdesignforbothsubmergedand transmucosal healing approaches.15,18Duototnolargonumboroonrollod pationts and implants, tnis nonintorvontional studymayalsosorvoasasurvoy,ogto assesspotentialreasonswhypatientslose teethandsubsequentlyrequestimplant troatmont.Fromtno852onrollodpationts, moro tnan 56% o tno rooordod tootn lossos woro duo to poriodontitis or oarios (Tablo 1). Tnoso valuos woro similar to tno roasons or tootn loss roportod proviously.25 In contrast, toothfractureortraumawasthereasonfor sligntlymorotnan16%otnooasos,sug-gestingthatnoncompliancewithoral hygienewasafarmorefrequentfactorfor tootn loss in tnis study. Similarly, tno distribu-tionofbonequalityamongthepatients seeking implant treatment was assessed for tno 1,355 sitos wnoro implants woro plaood. Tnisrovoalodtnattnoma|orityoimplants woroplaoodinbonoqualitytypo2or3 (86.6%,Tablo 2).Bonoqualitytypo1or4 wasrarelydocumented,whichisinaccor-dancewithotherassessmentsofthebone quality distribution.26 Tnoso valuos rohoot tno general situation in patients seeking implant treatment,therebyconrmingthatthecur-rontnonintorvontionalstudyroprosontstno real-world scenario of daily dental practice.Tnoourrontstudyisonooonlyaow suonnonintorvontionalstudiosindontal implantology. In contrast, controlled clinical trialsnavostriotlydohnodpationtinolusion andexclusioncriteriaandareoftenper-formedunderhighlycontrolledconditions, whichcanincreasethelikelihoodofmore avorablo outoomos. Largor trials tond to bo in the form of cohort studies, which can be prospootivo or rotrospootivo. Tnoso usually involvo pationts wno snaro a oommon don-talsituation(og,roquiringimplantsto replace hopeless teeth,27 pationts roooiving asimilarprosthesis,28,29roquiringvortioal augmentation,30roooivingsnortimplantsin posterior jaws,31 periodontally compromised patients,32,33edentulousmandible,34,35and sinusaugmentation36).Tnoadvantagooa nonintorvontionalstudyistnattnoporor-mance of a product, technique, or treatment oanboinvostigatodundoroonditionstnat mirrortnosotypioallysooninprivatoprao-tice settings.Onedrawbackofsuchlargeprospec-tivo longitudinal studios, nowovor, is tnat tno patientattritionratemaybemuchhigher than with controlled clinical trials.37 Most of thisisduetopatientsbeinglosttofollow-up, og duo to aotors suon as pationts mov-ingawayorchangingtheirdentist,not attondingsonodulodvisits,notboingoon-tactablebytheclinician,referralstoother olinioians(og,orprostnotiowork),oror other reasons. In other cases, there may be datamissingdespitethepatientattending or tno sonodulod visit, duo to inoonsistont/inoomplotodataontry,tnisisknowntobo VOLUME 44 NUMBEP 7 JULY/AUGUST 2013511QUI NTESSENCEI NTERNATI ONALFi l i ppi et almorecommonforsecondaryparameters, asthefocusisoftenontheprimaryout-come.38Tnoratooattritionintnoprosont studywas|ustovor30%.tnasboonsug-gostodtnatattritiono20%orgroatormay raise concerns about the possibility of bias in randomizod oontrollod trials,38 especially if there is a high rate of loss to follow-up in a partioular group o pationts, nowovor, duo tothelargenumberofpatientsandthe greaterheterogeneityofpatientsandindi-oationsinalargononintorvontionaltrial suchasthis,itseemslikelythattheriskof biasintroducedbypatientattritionmaybe substantiallyroduood.Tnorooro,altnougn many variablos in suon a study aro not oon-trolled, the predictability of the implant treat-ment was unlikely to be affected. CONCLUSIONTnisprospootivo,multioontor,nonintorvon-tional olinioal study domonstratod vory suo-oossuloutoomoswitnStraumannBono LovolSLAotivodontalimplants.nadaily dental practice situation without strict inclu-sion or exclusion criteria and no contraindi-catedmedicalconditionsorsurgical proooduros,aoumulativosurvivalratoo 98.5%andsuooossratoo96.0%woro aoniovod by a largo numbor o indopondont dontalpraotitionors.Tnoorostalbonolovol remainedunchangedforthemajorityof implantsandabonelossofgreaterthan 1 mmwasobsorvodorowortnan5%o implants.Tnus,tnorosultsroportodnoro wereconsistentwiththosethathadbeen reportedinselectedpatientsundermore controlled conditions.ACKNOWLEDGMENTSTheauthorsacknowledgethesupportofalltheclini-ciansinvolvedintheorganizationandexecutionofthe study.WealsorecognizethesupportofKellyJorkand JenniferJackson(StraumannUSA,Andover,US),Mara Messi,MichelMallaun,ColinMcKinnonandMartin Schuler(InstitutStraumann,Basel,Switzerland)inthe organization of the study and preparation of the manu-script, and Heinz Frei (International Team for Implantol-ogy [ITI], Basel, Switzerland) for valuable assistance with datacollection.DataanalysiswasprovidedbyDrMan-fredKlasser(gwdconsult,MhlheimamMain,Germa-ny).TheauthorswouldalsoliketoacknowledgeDr SimoneSchilling(LandshutNikola,Germany)forher extensive work in the documentation of cases. Clinicians didnotreceivefundingfortheadministrationofthe study,butreceivedanominalpaymentbasedonthe provisionofcompletedocumentationforeachpatient (ie, funding was on a per-case basis). With the exception of this, the authors report no conicts of interest associ-ated with the organization of the study.REFERENCES1.KollerB,AttW,StrubJR.Survivalratesofteeth, implants,anddoublecrown-retainedremovable prostheses:asystematicliteraturereview.IntJ Prosthodont 2011;24:109117.2.Tomasi C, Wennstrm JL, Berglundh T. Longevity of teethandimplants:asystematicreview.JOral Rehabil 2008;35(Suppl 1):2332.3.GanelesJ,WismeijerD.Earlyandimmediately restoredandloadeddentalimplantsforsingle-tooth and partial-arch applications. Int J Oral Maxil-lofac Implants 2004;19(Suppl):92102.4.AdellR,ErikssonB,LekholmU,BrnemarkPI,Jemt T. 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