Systemic antibiotics in the treatment of periodontitis

Systemic antibiotics in thetreatment of periodontitisMAGDA FERES, LUCIENE C. FIGUEIREDO, GEISLA M. SILVA SOARES &MARCELO FAVERI

The recognition of the microbial origin and speci-ficity of periodontal diseases in the late 1970s ledto an increased interest in the use of antimicro-bial agents in periodontal therapy to promote aselective suppression of the probable etiologicagents. Since then, several groups of investigatorshave started to examine the effect of systemicallyadministered antibiotics as adjuncts to conven-tional periodontal treatment, such as scaling androot planing. Unfortunately, for several years theresults of these investigations were inconclusiveand often contradictory, especially regarding theeffect of these agents on the microbial composi-tion of subgingival biofilm. This was largely aresult of limitations of the microbiological tech-niques available, as well as a lack of standardiza-tion of the clinical study designs. The majoradvances in laboratory and clinical researchmethods in the past decade have led to well-designed randomized clinical trials using cutting-edge diagnostic tests that have greatly contributedto determining the actual outcomes of severalperiodontal treatments. This article endeavored toprovide a ‘state of the art’ overview on the use ofsystemic antibiotics in the treatment of periodon-titis, based on the most recent literature on thistopic as well as on a compilation of data fromstudies conducted at the Center of Clinical Trialsat Guarulhos University (S~ao Paulo, Latin Amer-ica, Brazil) from 2002 to 2012. In order to providea better biological understanding of the use ofthese antimicrobials in periodontal treatment, thefirst part of this article presents an overview ofsome recent microbiological/ecological conceptsassociated with the etiology of periodontal infec-tions.

Microbiological basis forperiodontal treatment

The periodontal pathogens: a long search

The effective treatment of an infectious disease isdependent on accurate diagnosis of the microorgan-ism(s) implicated in its etiopathogenesis. This is notalways an easy goal to achieve, especially in cases ofmixed infections in areas of the body that are natu-rally contaminated with bacteria, such as the gastro-intestinal tract and oral cavity. Technical difficultiesin evaluating the complex subgingival microbiota,which is highly colonized by several species of strictanaerobes and fastidious pathogens, have greatlydelayed the correct diagnosis and treatment of peri-odontitis (197). New targeted diagnostic techniques,not dependent on the viability of the bacteria for theiridentification, such as immunoassays, PCR and DNAprobes, were introduced in the late 1980s and early1990s and gave rise to ‘the modern search’ for the eti-ological agents of destructive periodontal diseases(12, 32, 106, 199, 213, 224). From that time until recentyears these technologies have been further improved,and the introduction of high-throughput microbialdiagnostic techniques have promoted a rapidadvance in our understanding of the complex subgin-gival microbial composition. The results of thesestudies confirmed and extended data from earlyinvestigations about the role of certain microorgan-isms, including Aggregatibacter actinomycetemcomi-tans, Porphyromonas gingivalis, Treponema denticola,Tannerella forsythia, Prevotella intermedia, Parvi-monas micra, Fusobacterium nucleatum, Selenomon-as sputigena and Eubacterium nodatum, in the onsetand progression of periodontitis (17, 31, 36, 37, 48, 62,

Periodontology 2000, Vol. 67, 2015, 131–186 © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd

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65, 70, 71, 76, 124, 134, 147, 193, 201, 206, 207, 217).More recently, the introduction of open-endedmolecular diagnostic tests, including next-generationsequencing methods, rekindled the search for newperiodontal pathogens. The combined results of thestudies using targeted and open-ended tests suggestthat some other cultivable and not-yet cultivable/unrecognized microbial species might play a role inthe etiology of periodontitis. Some of the novel candi-date pathogens are species or phylotypes from thegenera Bacteroidetes (e.g. Porphyromonas endodon-talis and Bacteroidales [G-2] sp. oral taxon 274), Spiro-chaetes (e.g. Treponema lecithinolyticum andTreponema medium), Firmicutes (e.g. Filifactor alocisand S. sputigena) and Synergistetes (e.g. Fretibacteri-um sp. oral taxon 360 and Fretibacterium fastidiuo-sum) (48, 54, 102, 103). The phylum Candidatussaccharibacteria (TM7), the Archaea domain and her-pesviruses might also have an association withdisease (107, 109, 131, 153, 185).

In addition to this evident growth in our knowledgeabout the role of different pathogens in the etio-pathogenesis of periodontitis, some new ecologicalconcepts generated in the medical and dental fieldsin the past decades have also contributed to changingseveral paradigms in periodontal treatment. Some ofthese concepts are discussed below.

Ecological concepts in the treatment ofperiodontal diseases: the role of host-compatible species and the importanceof defining microbial profiles

One of the most important contributions of the mod-ern era of oral microbiology was probably the notionintroduced by Socransky and coworkers in the late1980s that not all bacterial species existing in the oralcavity are pathogenic. In fact, some are host-compati-ble or even beneficial (195, 196, 200). The species con-sidered as ‘beneficial’ included Veillonella parvula,Actinomyces sp., or the combination of Streptococcusoralis, Streptococcus mitis and Streptococcus interme-dius. Clusters of these microorganisms were observedin samples from sites that exhibited less active diseaseand responded more favorably to therapy (195). Thisconcept was extended and largely disseminated afterthe publication of the classic study ‘Microbial com-plexes in subgingival plaque’ (193). Using clusteranalysis and community ordination techniques, theauthors evaluated the composition of 13,261 subgin-gival biofilm samples from 160 subjects with chronicperiodontitis and 25 with periodontal health using40 DNA probes for host-compatible species and

periodontal pathogens. Three microbial complexes –

yellow, purple and green – harbored several speciesconsidered to be host-compatible, including V. parv-ula, Actinomyces odontolyticus, Streptococcus andCapnocytophaga species. Later on, a group of fourActinomyces species was also pointed out as beingimportant beneficial microorganisms (194). Thesemicrobial species were considered as early colonizersof the tooth surface, whose growth usually precedesthe multiplication of the predominantly gram-nega-tive species from the pathogenic orange and red com-plexes. The orange complex harbored 12 bacterialspecies, including Fusubacterium and Campylobacterspecies, E. nodatum, P. intermedia, Prevotella nigres-cens and Streptococcus constellatus. The red complexconsisted of three closely related pathogens – T. for-sythia, P. gingivalis and T. denticola – which weredetected at higher proportions in diseased sites thanin periodontally healthy sites and were strongly asso-ciated with probing depth and bleeding on probing.

These findings played a major role in our under-standing of the etiology of periodontal diseases, espe-cially chronic periodontitis. Furthermore, the resultsof these studies suggest that in order to obtain thera-peutic success, it is as important to foster the over-growth of host-compatible bacterial species as it is toeliminate or suppress the periodontal pathogens.Therefore, in order to establish more effective treat-ments for periodontitis, one would have to track notonly the presence or absence of a few pathogensbefore and after treatment but the changes occurringin the entire subgingival microbial profile. It is diffi-cult to measure the impact of these findings on theperiodontal research field. Only to provide the readerwith a reference, the paper outlined above, ‘Microbialcomplexes in subgingival plaque’ (193) has been citedover 900 times since its publication in 1998 (209).

The importance of defining the microbial profiles ofdifferent periodontal conditions in order to delineatemore specific treatments was rapidly recognized andthis motivated groups of investigators to evaluatelarge numbers of biofilm samples for the presence,levels and proportions of several pathogens, as well ashost-compatible bacterial species. Initially, the micro-bial profile of chronic periodontitis, the most commonperiodontal condition, was defined in different geo-graphic locations (23, 62, 65, 124, 216), and the resultsof these studies were largely in agreement with thestudy of Socransky et al. (193) in subjects from theUSA. However, information about less-prevalent con-ditions, such as localized and generalized aggressiveperiodontitis in young subjects, took a little longer tobecome available (36, 84). Figure 1 contains an exten-

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sion of the data described by Faveri et al. (36), who,for the first time, evaluated the microbial profile of agroup of young subjects with localized aggressive peri-odontitis. The data presented in Fig. 1 provide a com-parison between the microbial profiles of 50 subjectswith periodontal health, 290 with chronic periodonti-tis, 56 with generalized aggressive periodontitis and 15with localized aggressive periodontitis. The bacterialspecies were organized according to the microbialprofiles described by Socransky et al. (193), four Acti-nomyces species are shown in blue and A. actinomyce-temcomitans in light green. In agreement withprevious investigations (79, 80, 126, 219, 222), A. ac-tinomycetemcomitans was found in significantlyhigher proportions in subjects with aggressive peri-odontitis in comparison with those with chronic peri-odontitis or with periodontal health, who harboredvery low proportions (<1%) of this pathogen. How-ever, one point of note was the high proportions ofred complex species in all three periodontitis groups.This was an expected finding for subjects with chronicperiodontitis, but quite unexpected for very youngsubjects with localized disease (mean age, 15.2 years).To date, only a few previous studies have suggestedthat pathogens other than A. actinomycetemcomitanscould also be associated with the etiology of localizedaggressive periodontitis (44, 121, 145). Moreover, asone moves from health to disease, a significantdecrease in the proportions of Actinomyces specieswas observed, which was also expected. The novel

and interesting information about the host-compati-ble Actinomyces was their very low proportions inlocalized and generalized periodontitis in comparisonwith chronic periodontitis. These data might explainthe lower degree of plaque accumulation observed inaggressive periodontitis because the Actinomyces areimportant plaque formers. Furthermore, these bacte-rial species have been strongly associated with healthypatients (23, 124, 198) and their increased proportionsmay be necessary for a successful therapeutic out-come. These findings provide the basis for determin-ing microbiological endpoints for therapy. The overallsimilarity among the microbial profiles of the threedisease conditions, as well as the higher proportionsof red complex bacteria and lower proportions of Acti-nomyces species in all periodontitis groups in compar-ison with the healthy group, suggest that thetherapeutic protocols for these infections may notvary substantially.

Ecological concepts in the treatment ofperiodontal diseases: pathogens arelocated in the entire mouth, not only indeep periodontal pockets

Historically, the treatment of periodontal diseases hasbeen largely focused on deep periodontal pockets.There is an overall consensus that scaling and rootplaning should be restricted to intermediate and deeppockets, and that shallow sites should be avoided.

Fig. 1. Pie charts describing the mean proportions ofmicrobial complexes in subgingival biofilm samples takenfrom 50 subjects with periodontal health, 15 subjects withlocalized aggressive periodontitis, 56 subjects with gener-alized aggressive periodontitis and 290 subjects withchronic periodontitis. Nine subgingival biofilm sampleswere taken from each subject and were analyzed sepa-rately to determine their content of the 40 species of bac-teria listed in Fig. 2. The percentage of DNA probe countsfor each species was determined at each site, then aver-aged within a subject and then across subjects in each

group. The mean proportion of each species was summedin order to determine the proportion of each complex.The colors represent the different complexes described bySocransky et al. (193). Actinomyces spp. are representedin blue and A. actinomycetemcomitans in light green.The grey color represents species that did not fall intoany complex. The significance of differences amonggroups was determined using analysis of covariance,adjusted for mean age and Tukey’s multiple comparisontests (different letters indicate significant differencesamong groups).

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The rationale for this thought was the results fromstudies which showed that shallow sites might loseattachment after scaling and root planing (64, 83,164). In addition, it has been recognized that thepresence of deep pockets after treatment is an impor-tant risk factor for further disease progression (132,133) and comprehensive studies have shown thatperiodontal pathogens are more concentrated indeep pockets (71, 198). Therefore, focusing periodon-tal treatment to deep pockets may be considered asalmost an obvious and effective strategy. A less well-known factor is that even shallow pockets of subjectswith periodontitis can be highly colonized with sev-eral periodontal pathogens, a very unfortunate find-ing in the light of the current overall idea of treatingmostly deep pockets. This statement is illustrated inFig. 2, which presents the mean counts and propor-tions of 40 bacterial species in nonbleeding shallow(‘healthy’) sites, with probing depth ≤4 mm, in a

group of 295 subjects with advanced periodontitis, aswell as in 50 periodontally healthy individuals. Themean levels of 32 out of 40 bacterial species evaluatedwere statistically significantly elevated in the peri-odontitis subjects (Fig. 2, left panel), which was asomewhat expected result because these subjectsnormally present higher overall plaque levels. Themost interesting observation relates to the composi-tion of the subgingival microbial profile in the twogroups (Fig. 2, right panel). The ‘healthy’ sites of sub-jects with periodontitis presented statistically signifi-cantly higher mean proportions of some of the mostimportant periodontal pathogens, such as A. actino-mycetemcomitans, the three members of the red com-plex (T. forsythia, P. gingivalis and T. denticola) andfour from the orange complex (Campylobacter rectus,E. nodatum, P. micra and P. intermedia) in compari-son with the ‘healthy’ sites in periodontally healthysubjects. On the other hand, the overall proportion of

0.0 5.7 11.4 17.1 22.8

******

**

******

******

******

******

****

****

********

********

****

******

******

*****

***

A.gerencseriae A.israelii

A.naeslundii A.oris

A.odontolyticus V.parvulla S.gordonii

S.intermedius S.mitis

S.oralis S.sanguinis

A. actinomycetemcomitansC.gingivalis C.ochracea

C.sputigena E.corrodens

C.gracilis C.rectus

C.showae E.nodatum

F.nucleatum.ssp.nucleatum F.nucleatum.ssp.polymorphum

F.nucleatum.ssp.vincentii F.periodonticum

P.micra P.intermedia P.nigrescens

S.constellatus T.forsythia P.gingivalis T.denticola

E.saburreum G.morbillorum

L.buccalis P.acnes

P.melaninogenica N.mucosa

S.anginosus S.noxia

T.socranskii

0.0 6.3 12.7 19.0 25.3

***

***

***

***

******

******

******

Counts x 105 DNA probe counts (%)

Periodontal health n = 50

Periodontitis n = 295

Actinomyces

Purple

Yellow

Green

Orange

Red

Others

Fig. 2. Profiles of the mean counts (3105; left panel) andof mean proportions (%; right panel) of 40 taxa in sub-gingival biofilm samples taken from nonbleeding shallowsites (probing depth ≤4 mm) of 295 subjects with peri-odontitis and 50 subjects with periodontal health. Threesubgingival biofilm samples were taken from each subjectand were analyzed separately to determine their contentof 40 species of bacteria. The species were ordered and

grouped according to the microbial complexes describedby Socransky et al. (193). The mean values for each spe-cies were averaged within a subject and then across sub-jects in the two clinical groups. The significance ofdifferences between groups was determined using theMann–Whitney U-test adjusted for multiple comparisons[Socransky et al. (199)]; * P < 0.05; ** P < 0.01; ***P < 0.001.

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the host-compatible Actinomyces was increased, andof Actinomyces naeslundii was significantly increased,in healthy subjects. This information has been sup-ported by other studies (167, 198).

The presence of periodontal pathogens in otherenvironments of the oral cavity has also been thesubject of study of different groups of investigators(35, 68, 125, 181, 217, 218). Ximenez-Fyvie et al.(217, 218) used DNA probes for 40 bacterial speciesto examine the composition of supragingival andsubgingival biofilm samples and observed that thered complex species could also be detected insupragingival biofilm, especially in subjects withperiodontitis. Shibli et al. (181) described similarfindings in subjects with peri-implantitis. Later on,the presence of these strict anaerobes in other aero-bic environments of the mouth, such as the tongue,saliva and oral mucosa, were suggested (35, 125).The observation that strictly anaerobic pathogensmay be found in highly oxygenated environmentsof the oral cavity was quite unexpected, and mightbe explained by the protective effect of thebiofilm structure that offers several advantages tocolonizing species, such as protection from undesir-able environmental conditions (e.g. high oxygen lev-els) (24, 128).

The data described above have direct clinical impli-cations. They suggest that not only deep pockets, butalso shallow pockets and all the other oral surfacesdemand anti-infective treatment. In summary, suc-cessful periodontal treatment would require a com-plete ecological shift in the oral environment, from amicrobial profile related to disease to a profile com-patible with health.

Systemic antibiotics in thetreatment of periodontitis

This section will provide the reader with the mostrecent literature on the effects of systemic antibiot-ics in periodontal treatment as well as with someanalyses generated from the database of The Centerfor Clinical Research at Guarulhos University (LatinAmerica, Brazil). The database included a total of419 subjects: 74 with aggressive periodontitis and295 with chronic periodontitis (treated with scalingand root planing, alone or combined with differentantibiotics), and 50 periodontally healthy subjects.Clinical measurements were recorded at six sites pertooth. Subgingival biofilm samples were taken fromnine sites per subject at each experimental timepoint and were evaluated for their content of 40

bacterial species using checkerboard DNA–DNAhybridization. Scaling and root planing was com-pleted in a maximum period of 14 days, except forthe subjects in the study of Silva et al. (184), forwhich this period was extended to 21 days. The anti-biotic or placebo medications started immediatelyafter the first session of scaling and root planing,except for the subjects in the studies of Carvalhoet al. (14, 15) and Sampaio et al. (177), who startedmedications immediately after the last scaling androot planing session.

In order to facilitate the understanding of theseanalyses we will briefly present the clinical andmicrobial parameters that were used to evaluatetreatment effectiveness and to compare differenttherapeutic groups.

Clinical outcomes

The clinical endpoints for periodontal therapy arevery straightforward and include gain in clinicalattachment and reduction in probing depth, bleedingon probing and suppuration, and, most importantly,preclusion of further disease progression. Several ran-domized clinical trials, designed to test the effects ofdifferent systemic antibiotics, have used meanchanges in probing depth or clinical attachment levelin sites with initial probing depth of ≥7 mm as theprimary clinical outcome variable (59, 72, 130, 184).However, the significance of these parameters indetermining treatment efficacy has recently beenpondered by Sampaio et al. (177) and Feres et al.(42). These authors questioned the real clinicalimportance of having a residual site with either 8 mmor 7 mm, because both pockets may frequentlyrequire additional treatment. Furthermore, in thedaily practice, the clinician does not calculate thepatient’s mean change in probing depth of initiallydeep sites in order to determine the endpoint fortherapy. On the other hand, recent robust studies ofrisk assessment showed that the presence of residualpockets after treatment, especially those with a prob-ing depth of ≥5 mm, is one of the most important riskindicators for periodontal disease recurrence in sub-jects under periodontal maintenance for an averageof 11.3 years (132, 133). Other authors have also con-firmed the association between the presence of resid-ual pockets and the lack of periodontal stability (18,105). Lang & Tonetti (105) suggested that subjectsexhibiting nine or more, five to eight or at most foursites with a probing depth of ≥5 mm post-treatmentare considered at high, moderate or low risk for dis-ease recurrence, respectively. Therefore, the clinical


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parameters used in the analyses conducted in thissection were:� To compare different treatments (i.e. primary clin-

ical outcome variable): the mean number of resid-ual sites with probing depth ≥5 mm.

� To define excellent treatment response (i.e. clini-cal endpoint for treatment): the presence of ≤4sites with probing depth ≥5 mm (low risk for fur-ther disease progression).

Microbiological outcomes

Several recent studies assessing the effects of differentperiodontal therapies on the composition of the sub-gingival microbiota have shown that effective clinicalresults are obtained when the levels and proportionsof periodontal pathogens are reduced or eliminatedand the root surfaces are recolonized with a new bio-film community harboring higher proportions ofhost-compatible species (22, 26, 30, 66, 71, 108, 130,138, 184). This is a complex ecological shift thatinvolves a striking change in the levels and propor-tions of several bacterial species, making the defini-tion of the microbial endpoint for periodontaltreatment a rather challenging task.

In an attempt to define objective microbial end-points for periodontal treatment, we evaluated themicrobial composition of the best-responders sub-jects, among those treated with scaling and rootplaning, alone, or combined with systemic antibiot-ics (Table 1). A subject was considered to be amongthe best-responders, and therefore included in thisanalysis, if he/she presented with at most four siteswith a probing depth of ≥5 mm (i.e. a low-risk pro-file for further disease progression) (105, 132, 133) at3 months post-treatment, and maintained this pro-file for up to 1 year. At 3 months post-treatment,the mean proportions of the red complex in thisgroup of subjects were 2.7%; the upper quartile was4.2% and the median was 1.5%. Thus, the three redcomplex species summed, represented at most 4.2%of all 40 species evaluated in 75% of these subjects.Conversely, the mean proportions of Actinomyceswere 26.8%; the lower quartile was 15.1% and themedian was 24.1%. Thus, these four host-compatibleActinomyces species summed, represented at least15.1% of all 40 species evaluated in 75% of thesesubjects.

Therefore, the microbial parameters used in theanalyses conducted in this section were as follows.� to compare different treatments (i.e. primary

microbiological outcome variable): mean percent-age of red complex species.

� to define excellent treatment response (i.e. micro-biological endpoints for treatment): the presenceof ≤4.2% of red complex species and ≥ 15.1% ofActinomyces species.

Rationale for the use of adjunctiveantibiotics in the periodontal treatment

Scaling and root planing has been considered thegold standard treatment for periodontitis for almost100 years. The results of the studies that evaluatedthe clinical effects of scaling and root planing suggestan overall benefit in terms of reducing the percentageof sites presenting bleeding on probing and suppura-tion as well as a reduction in probing depth and again in clinical attachment (8, 20, 22, 26, 63, 83, 162,164). However, scaling and root planing does not leadto major clinical improvements in all subjects, espe-cially in cases of advanced disease and deep peri-odontal pockets (50, 113, 177). This is probablybecause scaling and root planing alone does notcause a sufficiently deep change in the subgingivalmicrobial composition to achieve and maintain aprofile compatible with periodontal health longitudi-nally (144, 177, 184). In order to test this hypothesis,we gathered the data of 75 subjects with advancedperiodontal disease treated with scaling and rootplaning, who were clinically and microbiologicallymonitored at baseline, 3 months, 6 months and1 year post-treatment, and the results are presentedin Fig. 3 and in Tables 2 and 3. The mean baselineprobing depth and clinical attachment level for thisgroup of subjects were 3.9 mm and 4.4 mm, respec-tively. The mean reduction in probing depth and gainin clinical attachment (Table 2) were beyond theexpected changes for scaling and root planing accord-ing to a meta-analysis (90) and a comprehensivereview (20). There was a statistically significant reduc-tion in the mean number of residual sites with prob-ing depth ≥5 mm, ≥6 mm and ≥7 mm from baselineto 3 months, which in general, was maintained at6 months and 1 year post-treatment (Table 3). Nev-ertheless, the mean number of residual sites withprobing depth ≥5 mm was still high at 1 year(17.9 � 15.2) and only 16% (12/75) of the subjectstreated with scaling and root planing reached theclinical endpoint for treatment (i.e. presented at mostfour sites with probing depth ≥5 mm). The mean pro-portions of the microbial complexes at baseline andafter treatment are presented in Fig. 3. An improve-ment in the subgingival microbial compositionoccurred at 3 months, as may be noticed by a statisti-cally significant reduction in the mean proportions of

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Table 1. Microbial characteristics of subgingival biofilm of ‘best responders’ subjects

Variables Mean SD Median LQ-UQ

Mean counts 9105

A. gerencseriae 3.14 3.61 2.33 1.32–3.49

A. israelii 3.39 4.91 2.00 1.42–3.50

A. naeslundii 2.47 2.72 1.96 1.13–3.01

A. oris 18.11 14.56 15.24 5.51–26.28

T. forsythia 4.1 9.50 0.6 0.0–2.4

P. gingivalis 1.8 4.01 0.1 0.0–1.1

T. denticola 0.8 1.85 0.2 0.0–1.0

Actinomyces sp.* 26.65 19.92 20.08 14.14–36.21

Purple complex 11.28 10.14 5.58 3.14–16.80

Yellow complex 23.26 24.92 11.67 4.89–36.89

Green complex 11.37 16.98 5.02 2.54–11.29

Orange complex 29.05 33.92 18.84 4.31–39.46

Red complex 6.59 11.28 1.46 0.11–6.84

Others 26.07 24.90 20.52 6.88–39.42

Mean proportions (%)

A. gerencseriae 2.59 1.95 2.33 1.18–3.37

A. israelii 2.95 2.84 2.29 1.20–3.55

A. naeslundii 2.76 3.62 1.61 0.54–3.17

A. oris 18.97 14.53 14.75 8.58–21.33

T. forsythia 1.75 2.92 0.34 0.00–2.00

P. gingivalis 0.69 1.23 0.07 0.00–0.74

T. denticola 0.35 0.58 0.14 0.00–0.48

Actinomyces sp.* 26.8 17.9 24.1 15.1–32.0

Purple complex 9.47 7.54 8.13 4.76–11.62

Yellow complex 15.65 10.90 14.38 7.31–23.15

Green complex 8.00 9.21 5.20 2.12–9.26

Orange complex 17.49 11.71 16.37 7.67–23.08

Red 2.74 3.50 1.50 0.07 –4.23

Others 19.88 12.47 18.63 12.40–26.54

% sites colonized at levels ≥105

T. forsythia 8.0 9.0 3.0 0.0–17.0

P. gingivalis 5.0 6.0 0.0 0.0–8.0

T. denticola 3.0 2.0 0.0 0.0–6.0

All red complex spcs. 1.0 2.0 0.0 0.0–3.0

The samples were taken from 45 subjects who showed a very good clinical response (‘best responders subjects’) at 3 months post-treatment (i.e. presented at mostfour sites with PD ≥ 5 mm – the clinical endpoint for treatment) and maintained this clinical profile for up to 1 year. Nine subgingival biofilm samples were takenfrom each subject at 3 months.*Including Actinomyces gerencseriae, Actinomyces israelii, Actinomyces naeslundii and Actinomyces oris.


137

red and orange complexes as well as an increase inthe Actinomyces species. This selective reduction incertain pathogens after scaling and root planing hasbeen shown in previous studies (3, 14, 22, 26, 43, 63,66, 88, 92, 100, 138, 161, 171, 182, 184) and suggeststhat although scaling and root planing does not targetspecific bacterial species, the good clinical outcomeassociated with this therapy is the result of a benefi-cial change in the composition of the subgingivalmicrobiota, which probably occurs during recoloniza-tion of the treated sites. After scaling and root plan-ing, the first colonizers from the yellow, purple andgreen complexes, as well as the Actinomyces species,re-emerge in greater proportions and the pathogensof the red and orange complexes recolonize moreslowly, probably because of their fastidious nature,and remain in lower proportions. Unfortunately, notall these changes are sustained over time. The datapresented in Fig. 3 show that even with the use oflongitudinal maintenance appointments, some recol-onization with red complex pathogens is observedduring the monitoring period. At 1 year post-treat-ment these pathogens still represented 11.4% of the

40 bacterial species evaluated, which may be consid-ered a relatively high value, and only 28% (21/75) ofthe treated subjects reached the suggested microbialendpoint for treatment.

0

25

50

75

100

Baseline 3 months 6 months 1 year

7.5 9.5 11.4

27.7

28.3

21.0 18.0 21.2

28.0

11.7

***

**

**

Mea

n p

erce

nta

ge

Actinomyces

Others

AB B

C

A

B B B

A

B28.0

B

27.4B

Fig. 3. Cumulative mean proportions of microbial com-plexes in subgingival biofilm samples taken from 75 sub-jects with advanced periodontitis at baseline, and at3 months, 6 months and 1 year post-scaling and rootplaning. Nine subgingival biofilm samples were taken fromeach subject at each time point and were analyzed sepa-rately to detrmine their content of the 40 species of bacte-ria listed in Fig. 2. The percentage of DNA probe counts foreach species was determined at each site, then averagedwithin a subject and then across subjects at each timepoint. The mean proportion of each species was summedin order to determine the proportion of each complex.The colors represent the different complexes described bySocransky et al. (193). The grey color (‘Others’) representsspecies that did not fall into any complex, and Actinomycesspp. are represented in blue. The significance of differ-ences among time points was determined using repeated-measures analysis of variance (**P < 0.01; *** P < 0.001)and Tukey’s multiple comparison test (different lettersindicate significant differences between time points).

Table 2. Effect of scaling and root planing on meanprobing depth reduction and clinical attachment gainbetween baseline and 3 months, baseline and 6 monthsand baseline and 1 year post-therapy in 75 subjects withadvanced periodontitis

Baselineprobingdepth

Variables Time period Mean value �SD (mm) (n = 75)

4–6 mm Probing depthreduction

0–3 months 1.2 � 0.5

0–6 months 1.3 � 0.5

0–1 year 1.3 � 0.5

Clinicalattachmentgain

0–3 months 1.0 � 0.5

0–6 months 1.1 � 0.4

0–1 year 1.2 � 0.5

≥7 mm Probing depthreduction

0–3 months 2.5 � 1.0

0–6 months 2.9 � 1.2

0–1 year 2.9 � 1.2

Clinicalattachmentgain

0–3 months 2.1 � 1.0

0–6 months 2.3 � 1.0

0–1 year 2.4 � 1.2

Table 3. Number of sites with probing depth ≥5, ≥6 and≥7 mm, at baseline and at 3 months, 6 months and 1year post-treatment in 75 subjects with advanced peri-odontitis treated with scaling and root planing

Probingdepth

Time point No. of sites with probingdepth according to thecut-off (specified incolumn 1) (n = 75)

≥5 mm Baseline 45.9 � 21.2a

3 months 19.0 � 16.5b

6 months 17.4 � 14.9b

1 year 17.9 � 15.2b


3 months 8.6 � 10.6b

6 months 8.2 � 10.4b

1 year 7.7 � 9.9b


3 months 4.5 � 7.9b

6 months 4.3 � 7.5b

1 year 3.5 � 6.6b

Values are given as mean � SD. The significance of differences over the courseof the study was assessed using Friedman’s and Dunn’s multiple comparisontests (different letters indicate significant differences between time points).

Feres et al.

138

In summary, scaling and root planing leads to areduction in the levels and proportion of some peri-odontal pathogens, but does not seem to modify thecomposition of the subgingival biofilm sufficientlyfor the new, beneficial, bacterial community tobecome established in a more definitive manner.Therefore, other forms of therapies, such as antibi-otics, have been used in conjunction with scalingand root planing in order to potentiate the effects ofthis treatment.

Local vs. systemic antibiotics and theconcern about the development ofbacterial resistance

Antibiotics can be used locally or systemically. Localrelease of antimicrobial agents or antibiotics is nor-mally carried out using fibers, gels, chips or micro-spheres (165). The greatest advantage of this usage isavoidance of the side effects of drugs prescribed sys-temically and a diminished chance of developing bac-terial resistance to the medications. Therefore,numerous studies have assessed the effects of locallydelivered antiseptics and antibiotics as adjuncts toperiodontal treatment (1, 7, 11, 51, 75, 78, 99, 143,157, 158, 203). However, the overall outcomes of thesetreatments were not found to be particularly promis-ing (53, 56, 95, 135, 155, 176, 204), which might bepartially explained by some of the ecological conceptsdiscussed earlier in this article, such as the notion ofperiodontal disease as an infection that affects theentire mouth, including shallow sites, saliva, tongueand cheeks. Thus, it was recognized that the use oflocalized therapies restricted to a subset of deep sub-gingival sites is particularly limited, and local antimi-crobial therapy has more commonly been usedduring the maintenance phase, for treating remainingand isolated active pockets (82, 91). Conversely, sys-temic antibiotics reach all the oral surfaces and fluids,in addition to having the potential to reach periodon-tal pathogens that eventually invade the host’s tissues(97, 172). The disadvantages of systemic antibioticsover locally applied antibiotics include adverse drugreactions (190), uncertain patient compliance (58,114) and lower concentration of the drug at subgingi-val sites (49). However, the severest criticism of theindiscriminate use of systemic antibiotics is the devel-opment of bacterial resistance. This phenomenon hasbeen of great concern in medicine and dentistry andis considered one of the primary reasons for failure intreating infectious diseases. Strains of subgingivalspecies that are resistant to commonly used antibiot-ics can be isolated from subgingival biofilm samples

(4–6, 13, 169, 210), although it is not clear whetherthis is a result of selection by the antibiotic of resis-tant organisms that already existed, or the ‘creation’of ‘new’ resistant species. Feres et al. (39, 41) deter-mined the prevalence and proportions of metronida-zole-, amoxicillin- and doxycycline-resistant bacteriain the subgingival biofilm and saliva samples of sub-jects with chronic periodontitis, during and after theadministration of these agents. During antibioticadministration, the proportion of resistant isolatesincreased for all three tested antibiotics in both bio-film and saliva, falling to baseline levels by 90 days.Most of the antibiotic-resistant species detected dur-ing and after the administration of the drugs werealso detected before their administration, suggestingthat this transient increase in the proportion of resis-tant isolates was most probably the result of an over-growth of intrinsically resistant species present insubgingival biofilm before utilization of the antimi-crobial agent than the emergence of new resistantstrains. Similar results were described by Rodrigueset al. (169) for tetracycline and by Haffajee et al. (66)for azithromycin. Overall examination of data fromthese studies suggests that there was no compellingevidence to indicate the emergence of antibiotic-resistant strains of the taxa tested. However, it is con-ceivable that antibiotic-resistant strains appearedwhich could not be detected by the DNA probes usedin these investigations. Detecting the emergence ofantibiotic-resistant taxa, previously antibiotic sensi-tive, in an ecosystem is not a trivial undertaking, butclearly such events must occur otherwise there wouldbe no concern about the ‘antibiotic resistance’ prob-lem worldwide. Unfortunately, the frequency withwhich such events occur during the typical use ofantibiotics in the treatment of periodontal patients isstill unknown. Thus, the recommendation of thesedrugs in periodontology should follow the same pre-cepts as those of medicine, which is, whenever theirreal efficacy for the treatment of a certain infectionhas been proved. This certainty may only be reachedby means of profound knowledge of the current sci-entific literature about the use of these agents. Themain questions that should be asked in this regardare: (i) Which drugs should be used? (ii) For whichcases? (iii) Which are the best protocols (doses anddurations)? (iv) In which phase of the mechanicaltherapy (together or right after)? The following subi-tems present and discuss the latest developments onthis topic in an effort to answer these questions andto guide the clinicians’ decision on the use of sys-temic antibiotics as adjuncts to periodontal treatmentin daily clinical practice.


139

Which antibiotic(s) would provide themost predictable results?

One of the first reports on the effectiveness ofsystemic antibiotics in periodontal treatment waspublished in 1979. A 13-year-old patient with local-ized juvenile periodontitis (at present denominatedlocalized aggressive periodontitis), who did notrespond to conventional therapy, was given a courseof tetracycline, which was followed by a marked clini-cal and microbiological improvement (189). Severalsubsequent clinical investigations showed that tetra-cycline or its semisynthetic derivatives, such as doxy-cycline and minocycline, were effective for thetreatment of localized aggressive periodontitis (110,126, 127, 150, 151). Many studies focused on the elim-ination or reduction of A. actinomycetemcomitans,which was, for a long time, highlighted as the solepathogen associated with aggressive periodontitis inyoung individuals and does not respond well tomechanical debridement (12, 144, 149, 187, 222). Sub-sequently, almost all available antibiotics have beentested for use in the treatment of chronic or aggres-sive periodontitis, such as amoxicillin (40, 168, 170),azithromycin (29, 34, 47, 60, 61, 66, 72, 77, 129,152, 177, 192, 220), clindamycin (183), doxycycline(10, 183, 215), metronidazole (14, 15, 40, 42, 66, 72,111, 130, 170, 183, 184, 215), tetracycline (163) and acombination of metronidazole and amoxicillin (2, 10,16, 18, 19, 33, 42, 50, 55, 59, 85, 95, 122, 123, 130, 136,138, 139, 141, 160, 166, 170, 184, 211, 212, 214, 215,221). The experimental designs and main findings ofthe randomized clinical trials on the effects of sys-temic antibiotics in the periodontal treatment pub-lished from January 2001 to August 2012 arepresented in Tables 4 and 5. Table 4 summarizes thestudies conducted in Latin America (Brazil and Chile)and Table 5 summarizes the studies conducted inNorth America (the USA), Europe (Sweden, the UK,Spain, Switzerland, Italy, the Netherlands, Germany,Turkey and Greece) and Asia (Japan, Iran and China).

The first two systematic reviews with meta-analysisthat directly compared the effects of different adjunc-tive systemic antibiotics in the treatment of periodon-titis were published in the early 2000s and wereunable to assign superiority to a certain antibiotic orcombination of drugs owing to the limited number ofstudies using each of the antibiotic protocols and thesubstantial differences among the study designs (67,87). However, the overall evaluation of the random-ized clinical trials published in the last decade(Tables 4 and 5) suggests that the most promisingdrugs for the treatment of periodontal diseases are

metronidazole or the combination of metronidazole+ amoxicillin, a protocol originally proposed by Win-kelhoff and coworkers for the treatment of A. actino-mycetemcomitans-associated periodontitis (211).With the aim of directly comparing these two antibi-otic protocols, we conducted the following analysis ina group of subjects with either aggressive or chronicperiodontitis. The data are a compilation and exten-sion of those described by Mestnik et al. (138, 139)and Feres et al. (42), and the results are presented inTables 6–8 and Figs 4 and 5. After a baseline-moni-toring visit, subjects received quadrant scaling androot planing, alone or combined with 400 mg of met-ronidazole or with 400 mg of metronidazole and500 mg of amoxicillin. The antibiotics were adminis-tered three times daily for 14 days and started at thesame time as the mechanical therapy. Subjects in thecontrol and metronidazole groups received placebo.Clinical and microbiological monitoring, as well asperiodontal maintenance, were performed at3 months, 6 months and 1 year post-treatments. Themean baseline probing depth and clinical attachmentlevel were, respectively, 3.9 mm and 4.3 mm for thescaling and root planing group, 3.7 mm and 4.2 mmfor the metronidazole group and 3.9 mm and 4.3 mmfor the metronidazole + amoxicillin group. At base-line, no statistically significant differences amonggroups were observed for any clinical parameter eval-uated and for the number of subjects reportingadverse events, or between the two antibiotic groupsfor the individual adverse effects reported (P > 0.05,data not shown). Table 6 presents the mean numberof sites with probing depth ≥5 mm, ≥6 mm and≥7 mm at all time-points. Even though the number ofdeep sites did not differ among the three groups atbaseline, the two antibiotic-treated groups presentedstatistically significantly fewer of these three catego-ries of residual sites at all follow-up appointments.Interestingly, subjects taking antibiotics continued toshow some further reduction in deep sites from3 months to 1 year post-treatment, whereas thisimprovement was less marked for subjects treatedwith scaling and root planing only, especially for siteswith probing depth ≥5 mm. Clear difference wasobserved among groups for the mean number of siteswith probing depth ≥5 mm at 1 year post-treatment.Subjects receiving scaling and root planing only stillhad a mean of 18 of these residual sites, comparedwith 8 and 5.3 in the metronidazole and metronida-zole+amoxicillin groups, respectively. Table 7 pre-sents the percentage of subjects reaching the clinicalendpoint for treatment. All subjects included in thisanalysis had at least nine sites with probing depth

Feres et al.

140

Tab

le4.

Ran

domized

clinical

trialstestingtheeffectsofsystemic

antibiotics

ontheperiodontaltreatmen

tco

nducted

inLa

tinAmerica(200

1–20

12)

Countryan

dReferen

ces

Duration

Placebo

(Yes/N

o)

Antibiotican

ddose

Total

population/

no.o

fgroups

Age

(yea

rs)

No.o

fsm

oke

rsIn

itialm

ean

pro

bing

dep

th(m

m)

Disea

seAntibiotictherap

y(duration/m

omen

t)

(a)Exp

erim

entald

esigns

Brazil

Rodrigu

eset

al.

(168

)3months

No

Amoxicillin/

Clavu

lanic

acid

875mg

30/2

Notstated

02.7–

3.2

Chronic

periodontitis

Twicedaily

for14

day

s,starting24

hours

before

thefirstscalingan

droot

planingsession

Carva

lhoet

al.

(14,

15)

3months

Yes

Metronidazole

400mg

44/4

45�

612

3.7–

4.1

Chronic

periodontitis

Twicedaily

for10

day

s,startingafterscalingan

drootplaning

Haa

set

al.(60

,61

)1ye

arYes

Azithromycin

500mg

25/2

13–2

65

4.7–

4.8

Agg

ressive

periodontitis

Once

daily

for3day

s,startingat

thefirstscaling

androotplaningsession

Matarazzo

etal.

(130

)3months

Yes

Metronidazole

400mgAmoxicillin

500mg

43/3

41.8

�7.1

433.7–

4.0

Chronic

periodontitis

Threetimes

daily

for

14day

s,startingat

the

firstscalingan

droot

planingsession

Ribeiro

etal.(16

6)6months

Yes

Metronidazole

250mgAmoxicillin

375mg

25/2

30–6

60

6.2–

6.4

Chronic

periodontitis

Threetimes

daily

for

7day

s,startingat

thefirst

scalingan

drootplaning

session

Mestnik

etal.

(138

,139

)3months

1ye

arYes

Metronidazole

400mgAmoxicillin

500mg

30/2

27.2

�3.7

04.1–

4.3

Agg

ressive

periodontitis

Threetimes

daily

for

14day

s,startingat

the

firstscalingan

droot

planingsession

Sampaioet

al.

(177

)1ye

arYes

Azithromycin

500mg

40/2

44.1

�6.2

104.8–

5.0

Chronic

periodontitis

Once

daily

for5day

s,startingafterscalingan

drootplaning

Silvaet

al.(18

4)3months

Yes

Metronidazole

400mgAmoxicillin

500mg

51/3

45.5

�9.6

03.6–

3.8

Chronic

periodontitis

Threetimes

daily

for

14day

s,startingat

the

firstscalingan

droot

planingsession


141

Tab

le4.

(Con

tinued

)

Countryan

dReferen

ces

Duration

Placebo

(Yes/N

o)

Antibiotican

ddose

Total

population/

no.o

fgroups

Age

(yea

rs)

No.o

fsm

oke

rsIn

itialm

ean

pro

bing

dep

th(m

m)

Disea

seAntibiotictherap

y(duration/m

omen

t)

Varelaet

al.(21

2);

Helleret

al.(85

)6months

Yes

Metronidazole

250mgAmoxicillin

500mg

35/2

32.5

�4.5

44.2–

4.3

Agg

ressive

periodontitis

Threetimes

daily

for

10day

sStartingat

the

last

session

Full-mouth

ultrasonic

deb

ridmen

t

Casarin

etal.(16

)6months

Yes

Metronidazole

250mgAmoxicillin

375mg

24/2

28.5

�6.1

06.4–

6.6

Agg

ressive

periodontitis

Threetimes

daily

for

7day

s,startingat

thefirst

scalingan

drootplaning

session

Feres

etal.(42

)1ye

arYes

Metronidazole

400mgAmoxicillin

500mg

120/3

44.8

�8.4

03.7–

3.9

Chronic

periodontitis

Threetimes

daily

for

14day

s,startingat

the

firstscalingan

droot

planingsession

Chile

L� opez

etal.(12

3)1ye

arYes

Metronidazole

250mgAmoxicillin

500mg

22/2

38–6

89

2.4–

2.8

Chronic

periodontitis

Threetimes

daily

for

7day

s,startingat

thefirst

scalingan

drootplaning

visit

L� opez

etal.(12

2)1ye

arYes

Metronidazole

250mgAmoxicillin

500mg

165/2

35–6

546

Notstated

Chronic

periodontitis

Threetimes

daily

for

7day

s,starting1wee

kbefore

scalingan

droot

planing

Countryan

dReferen

ces

Treatmen

tPrincipal

clinical

findings

Principal

micro

biologica

lfindings

(method)

Test

Control

(b)Mainfindings

Brazil

Rodrigu

eset

al.(16

8)Full-mouth

scalingan

drootplaning

(twosessions)

+am

oxicillin/

clav

ulanic

acid

Full-mouth

scalingan

drootplaning

Nodifference

betwee

ngroupsin

full-mouth

mea

nprobingdep

th(full-mouth

scalingan

drootplaning+

amoxicillin/clavu

lanic

acid,

0.8�

0.6mm;full-mouth

scalingan

droot

planing,

0.9�

0.4mm)(P

>0.05

)

No

Feres et al.

142

Tab

le4.

(Con

tinued

)

Countryan

dReferen

ces

Treatmen

tPrincipal

clinical

findings

Principal

micro

biologica

lfindings

(method)

Test

Control

Carva

lhoet

al.(14

,15)

Scalingan

droot

planing+

metronidazole

Scalingan

droot

planing+

supragingiva

lscaling+

placebo

Scalingan

droot

planing+

supragingiva

lscaling+

metronidazole

Scalingan

droot

planing+

placebo

Groupstrea

tedwithmetronidazole

(withor

withoutsu

pragingiva

lsca

ling)

showed

grea

ter

mea

nprobingdep

threductionin

siteswith

initialp

robingdep

th≥7

mm

than

theother

groups(P

<0.05

).Nodifference

betwee

ngroupsin

clinical

attach

men

tga

in(P

>0.05

)at

3months

Counts

ofP

orphyrom

onas

gingiva

lis,Tan

nerella

forsythia

andTrepon

emaden

ticola

were

only

reducedin

supragingiva

lscalingan

dsu

pragingiva

lscaling+

metronidazole

groups

at3months(P

<0.05

)(checke

rboardDNA–D

NA

hyb

ridization)

Haa

set

al.(60

,61)

Scalingan

droot

planing+

azithromycin

Scalingan

droot

planing+

placebo

Nodifference

betwee

ngroupsin

mea

nprobing-

dep

threduction(azithromycin,3

.5�

0.2mm;

scalingan

drootplaning,

2.7�

0.5mm)an

dclinical

attach

men

tga

in(azithromycin,

2.0�

0.2mm;sca

lingan

drootplaning,

1.3�

0.3mm)(P

>0.05

)in

siteswithinitial

probingdep

th≥7

mm

at1ye

ar.T

estgroup

showed

ahigher

mea

npercentage

oftee

thwithclinical

attach

men

tga

in≥1

mm

(azithromycin:8

1.3�

3.3mm;sca

lingan

drootplaning:

63.6

�7.3mm)(P

<0.05

)

Leve

lsofm

ost

bac

terial

species

decreased

inboth

groupswith

asimila

rpattern

at1ye

ar(P

>0.05

)(checke

rboardDNA

–DNAhyb

ridization)

Matarazzo

etal.(13

0)Sc

alingan

droot

planing+

metronidazole

Scalingan

droot

planing+

metronidazole+am

oxicillin

Scalingan

droot

planing+

placebo

Themetronidazole+am

oxicillingroupsh

owed

grea

terfull-mouth

mea

nprobingdep

threduction(1.0

mm)an

dclinical

attach

men

tga

in(0.9

mm)than

themetronidazole

(probingdep

th,0

.8mm;c

linical

attach

men

t,0.6mm)an

dco

ntrol(probingdep

th,0

.6mm;

clinical

attach

men

t,0.5mm)groups(P

<0.05

)at

3months

Thegrea

test

reductionin

the

redco

mplexoccurred

inmetronidazole+am

oxicillin

(from

32%

to2%

)an

dmetronidazole

(from

25%

to4%

)groups,follo

wed

bythe

controlg

roup(from

33%

to8%

)at

3months

(checke

rboardDNA–D

NA

hyb

ridization)


143

Tab

le4.

(Con

tinued

)

Countryan

dReferen

ces

Treatmen

tPrincipal

clinical

findings

Principal

micro

biologica

lfindings

(method)

Test

Control

Ribeiro

etal.(16

6)Onesessionoffull-mouth

ultrasonic

deb

ridmen

t+metronidazole+

amoxicillin

Onesessionoffull-mouth

ultrasonic

deb

ridmen

t+placebo

Nodifference

betwee

ngroupsin

mea

nprobing

dep

threductionin

siteswithinitialp

robing

dep

th≥7

mm

(metronidazole,3

.9�

0.9mm;

Full-mouth

ultrasonic

deb

ridmen

t:3.4�

0.7mm)(P

>0.05

).Testgroupsh

owed

ahigher

mea

npercentage

ofsites

withclinical

attach

men

tga

inof≥

2mm

(metronidazole,

58.0%;full-mouth

ultrasonic

deb

ridmen

t,43

.5%)(P

<0.05

)at

6months

Both

therap

ieswere

comparab

le(P

>0.05

)in

loweringperiodontal

pathoge

nsat

6months

(rea

l-timePCR)

Mestnik

etal.(13

8,13

9)Sc

alingan

droot

planing+

metronidazole+am

oxicillin

Scalingan

droot

planing+

placebo

Thetest

groupsh

owed

grea

termea

nprobing

dep

threduction(m

etronidazole+am

oxicillin,

4.2�

1.4mm;sca

lingan

drootplaning,

2.8�

1.1mm)an

dclinical

attach

men

tga

in(m

etronidazole+am

oxicillin,3

.4�

1.2mm;

scalingan

drootplaning,

2.3�

1.1mm)

(P<0.05

)in

siteswithinitialp

robingdep

th≥7

mm

at1ye

ar.T

estgroupsh

owed

alower

mea

nnumber

ofsites

withprobingdep

th≥5

mm

than

theco

ntrolg

roupat

1ye

ar(6.4

�7.2an

d23

.1�

13.1

sites,resp

ective

ly)

(P<0.05

)

Themost

ben

eficial

chan

ges

wereobserved

inthe

metronidazole+am

oxicillin

group,w

hichsh

owed

the

lowestproportionsofred

complexsp

eciesas

wella

sa

sign

ifica

ntdecreasein

the

orange

complexat

3months.

Resultsfrom

1ye

ardataare

notye

tpublished

(checke

rboardDNA–D

NA

hyb

ridization)

Sampaioet

al.(17

7)Sc

alingan

droot

planing+

azithromycin

Scalingan

droot

planing+

placebo

Nodifference

betwee

ngroupsin

mea

nprobing

dep

threduction(azithromycin,3

.4�

1.7mm;

scalingan

drootplaning,

3.8�

1.9mm)an

dclinical

attach

men

tga

in(azithromycin,

2.7�

1.7mm;sca

lingan

drootplaning,

2.3�

1.7mm)(P

>0.05

)in

siteswithinitial

probingdep

th≥7

mm

at1ye

ar.T

hemea

nnumber

ofrem

ainingsiteswithprobingdep

th≥5

mm

was

highin

both

groupsat

1ye

ar(ffi

17)

Theco

unts

andproportionsof

someperiodontalp

athoge

ns

wereeq

ually

reducedin

both

groups.Theproportionsofred

complexsp

ecieswere

relative

lyhighin

both

groups

at1ye

ar(checke

rboard

DNA–D

NAhyb

ridization)

Feres et al.

144

Tab

le4.

(Con

tinued

)

Countryan

dReferen

ces

Treatmen

tPrincipal

clinical

findings

Principal

micro

biologica

lfindings

(method)

Test

Control

Silvaet

al.(18

4)Sc

alingan

droot

planing+

metronidazole;

Scalingan

droot

planing+

metronidazole+am

oxicillin

Scalingan

droot

planing+

placebo

Both

test

groupssh

owed

grea

termea

nprobing

dep

threduction(m

etronidazole+am

oxicillin,

3.6�

0.6mm;m

etronidazole,3

.3�

1.0mm;

scalingan

drootplaning,

2.3�

1.1mm)an

dclinical

attach

men

tga

in(m

etronidazole+am

oxicillin,3

.0�

0.7mm;

metronidazole,2

.7�

1.3mm;sca

lingan

droot

planing,

2.1�

1.0mm)(P

<0.05

)in

siteswith

initialp

robingdep

th≥7

mm

at3months.The

metronidazole+am

oxicillingroupsh

owed

alower

mea

nnumber

ofsites

(mea

n=5.3)

with

probingdep

th≥5

mm

than

theco

ntrolg

roup

(mea

n=13

.3)(P

<0.05

)at

3months

Scalingan

drootplaning+

metronidazole+am

oxicillin

was

theonly

trea

tmen

tthat

sign

ifica

ntlyreducedtheleve

lsan

dproportionsofa

llred

complexpathoge

nsan

delicited

asign

ifica

ntgrea

ter

ben

eficial

chan

gein

the

microbialp

rofile

at3months

(checke

rboardDNA–D

NA

hyb

ridization)

Varelaet

al.(21

2);

Helleret

al.(85

)PhaseI:Full-mouth

ultrasonic

deb

ridem

ent(irrigationofp

ock

ets,

garglin

gan

dbrush

ingthetongu

e–

chlorhexidine0.2%

,45

day

s+metronidazole+am

oxicillin

PhaseII(started

awee

kafterPhase

I):sca

lingan

drootplaning

+irriga

tionofp

ock

ets

PhaseI:eq

ual

tothetest

group+placebo

PhaseII:e

qual

tothetest

group

Nodifference

betwee

ngroupsin

full-mouth

mea

nprobingdep

threduction

(metronidazole+am

oxicillin,1

.5mm;

full-mouth

ultrasonic

deb

ridmen

t,0.9mm)

(P>0.05

)an

dclinical

attach

men

tga

in(m

etronidazole+am

oxicillin,1

.2mm;

full-mouth

ultrasonic

deb

ridem

ent,0.7mm)

(P>0.05

)at

6months.Four-hundredan

dtw

enty-foursitesin

theco

ntrolg

roupan

d26

3sitesin

thetest

group(P

<0.05

)did

not

resp

ondto

trea

tmen

tan

dwere

re-instrumen

tedat

3months

Both

therap

ieswere

comparab

lein

lowering

periodontalp

athoge

nsat

6months(checke

rboard

DNA–D

NAhyb

ridization)

Casarin

etal.(16

)Onesessionoffull-mouth

ultrasonic

deb

ridmen

t+metronidazole+

amoxicillin

OnesessionofF

ull-mouth

ultrasonic

deb

ridmen

t+placebo

Thetest

groupsh

owed

grea

termea

nprobing

dep

threductionin

siteswithinitialp

robing

dep

th≥7

mm

(4.1

�1.4mm)than

theco

ntrol

group(3.3

�0.6mm)(P

<0.05

)at

6months.

Noad

ditional

ben

efits

inclinical

attach

men

tga

inwereobserved

inthetest

group

Both

therap

ieswere

comparab

le(P

>0.05

)in

loweringperiodontal

pathoge

nsat

6months(rea

ltimePCR)


145

Tab

le4.

(Con

tinued

)

Countryan

dReferen

ces

Treatmen

tPrincipal

clinical

findings

Principal

micro

biologica

lfindings

(method)

Test

Control

Feres

etal..(42)

Scalingan

droot

planing+

metronidazole;

scalingan

droot

planing+

metronidazole+am

oxicillin

Scalingan

droot

planing+

placebo

Testgroupssh

owed

grea

termea

nprobing-

dep

threduction(m

etronidazole+am

oxicillin,

4.1�

0.7mm;m

etronidazole,3

.9�

0.9mm;

scalingan

drootplaning,

3.1�

1.4mm)an

dclinical

attach

men

tga

in(m

etronidazole+am

oxicillin,3

.4�

0.8mm;

metronidazole,3

.1�

1.1mm;sca

lingan

droot

planing,

2.6�

1.2mm)(P

<0.05

)in

siteswith

initialp

robingdep

th≥7

mm

at1ye

ar.B

oth

test

groupssh

owed

alower

mea

nnumber

of

siteswithprobingdep

th≥5

mm

than

the

controlg

roupat

1ye

ar(m

etronidazole+am

oxicillin,4

.7�

6.0sites;

metronidazole,6

.3�

7.3sites;scalingan

droot

planing,

16.1

�15

.6sites)

(P<0.05

)

No

Chile

L� opez

etal.(12

3)Su

pragingiva

lscaling+

metronidazole+am

oxicillin

Supragingiva

lscaling+

scalingan

droot

planing+

placebo

Nodifference

betwee

ngroupsin

full-mouth

mea

nprobingdep

th(m

etronidazole+am

oxicillin,0

.8mm;sca

ling

androotplaning,

0.5mm)an

dclinical

attach

men

tga

in(m

etronidazole+am

oxicillin,

0.3mm;full-mouth

ultrasonic

deb

ridmen

t,0.17

mm)(P

>0.05

)at

1ye

ar.T

hemea

npercentage

ofsites

withclinical

attach

men

tga

in>2mm

was

higher

inthetest

group

(3.8%)than

intheco

ntrolg

roup(1.1%),but

thedifference

was

notstatistica

llysign

ifica

nt

Therewerenostatistica

llysign

ifica

ntdifferencesat

any

timepointbetwee

ngroups

(P>0.05

)(checke

rboardDNA

–DNAhyb

ridization).

L� opez

etal.(12

2)Su

pragingiva

lsca

ling+

scalingan

drootplaning+

metronidazole

+am

oxicillin

Supragingiva

lscaling+

placebo

Thetest

groupsh

owed

alower

mea

npercentage

ofsites

withprobingdep

th≥4

mm

(P<0.05

)at

1ye

ar

No

Feres et al.

146

Tab

le5.

Ran

domized

clinical

trialstestingtheeffectsofsystemic

antibiotics

intheperiodontaltreatmen

tco

nducted

inNorthAmerica,

European

dAsia

Geo

grap

hic

Reg

ion/

Referen

ces

Duration

Placebo

(Yes/N

o)

Antibiotic/dose

Total

population/

no.o

fgroups

Age

(yea

rs)

No.o

fsm

oke

rsIn

itialm

ean

pro

bing

dep

th(m

m)

Disea

seAntibiotictherap

y(duration

andmomen

t)

(a)Exp

erim

entald

esigns

NorthAmerica

Feres

etal.

(40)

1ye

arNo

Metronidazole

250mg

Amoxicillin50

0mg

17/2

44�

13Notstated

3.2–

3.4

Chronic

periodontitis

Threetimes

daily

for14

day

s.Startingat

thefirstscaling


Masca

renhas

etal.(12

9)6months

No

Azithromycin

250mg

31/2

46�

1031

3.5–

4.2

Chronic

periodontitis

Once

daily

for5day

sStarting

attheseco

ndscalingan

drootplaningsession

Haffajeeet

al.

(66,

72)

1ye

arNo

Azithromycin

500mg

Metronidazole

250mg

Sub-antibac

terial

dose

doxycylin

e20

mg

92/4

45�

129

2.9–

3.3

Chronic

periodontitis

Azithromycin,o

nce

daily

for

3day

sMetronidazole,threetimes

daily

for14

day

sSu

b-antibac

terial

dose

doxycylin

e,tw

icedaily

for

12wee

ksStartingat

thefirstscaling


Dastooret

al.

(29)

6months

Yes

Azithromycin

500mg

30/2

51�

8.1

302.8–

3.2

Chronic

periodontitis

Once

daily

for3day

sStartingaftersu

rgery

Goodsonet

al.

(50)

2ye

ars

No

Metronidazole

250mg

Amoxicillin50

0mg

Loca

ltetracycline

delivery–fiber

(1.7

mg/tooth)

187/8

>20

years

755.9–

6.2

Chronic

periodontitis

Metronidazole,threetimes

daily

for14

day

sAmoxicillin,twicedaily

for

14day

sStartingat

thefirstscaling

androotplaningvisit

Loca

ltetracyclinedelivery–

fiber

–afterscalingan

droot

planing

Euro

pe

Winke

letal.

(214

)6months

Yes

Metronidazole

250mg

Amoxicillin35

0mg

49/2

28–6

332

4.4

Chronic

periodontitis

Threetimes

daily

for7day

sStarting6wee

ksafterscaling

androotplaning


147

Tab

le5.

(Con

tinued

)

Geo

grap

hic

Reg

ion/

Referen

ces

Duration

Placebo

(Yes/N

o)

Antibiotic/dose

Total

population/

no.o

fgroups

Age

(yea

rs)

No.o

fsm

oke

rsIn

itialm

ean

pro

bing

dep

th(m

m)

Disea

seAntibiotictherap

y(duration

andmomen

t)

Ram

berget

al.

(163

)13

years

No

Tetracycline25

0mg

115/2

23–6

666

3.9–

4.2

Adva

nced

periodontitis

Fourtimes

daily

for21

day

sStartingbefore

scalingan

drootplaning

Sigu

schet

al.

(183

)2ye

ars

No

Doxycycline20

0mg

Metronidazole

500mg

Clin

dam

ycin

150mg

48/4

32.4

05.5–

5.9

Rap

idly

progressive

periodontitis

Doxycycline,

once

daily;

metronidazole,twicedaily;

and

clindam

ycin,fourtimes

aday

for8day

sStartingafterfull-mouth

scalingan

drootplaning

Smithet

al.

(192

)22

wee

ksYes

Azithromycin

500mg

44/2

42.6

�8.5

103.2–

3.4

Chronic

periodontitis

Once

daily

for3day

sStaring

atthelast

wee

kofsca

lingan

drootplaning

Rooney

etal.

(170

)6months

Yes

Metronidazole

200mg

Amoxicillin25

0mg

66/4

20–4

50

Just

per

catego

ries

ofsites

Chronic

periodontitis

Threetimes

daily

for7day

sStartingafterscalingan

drootplaning

Ehmke

etal.

(33)

2ye

ars

No

Metronidazole

250mg

Amoxicillin37

5mg

35/2

51.1

�10

.73

Just

per

catego

ries

ofsites

Chronic

periodontitis

Threetimes

daily

for8day


drootplaning

Guerrero

etal.

(59)

6months

Yes

Metronidazole

500mg

Amoxicillin50

0mg

41/2

16–3

59

4.1

Agg

ressive

periodontitis

Threetimes

daily

for7day

sStartingat

thefirstscaling

androotplaningvisit

Mombelie

tal.

(142

)1ye

arYes

Metronidazole

250mg

Amoxicillin37

5mg

16/2

25–6

56

6.8–

7.7

Chronic

periodontitis

Threetimes

daily

for7day


drootplaning

Xajigeo

rgiou

etal.(21

5)6months

No

Metronidazole

500mg

Amoxicillin50

0mg

doxycycline10

0mg

43/4

22–4

915

4.2 –

4.7

Agg

ressive

periodontitis

Metronidazole,a

moxicillin,

threetimes

daily

for7day

sDoxycycline,

once

daily

for

14day


drootplaning

Cionca

etal.

(18,

19)

6months

Yes

Metronidazole

500mg

Amoxicillin37

5mg

51/2

25–7

016

4.3–

4.4

Chronic

periodontitis

Threetimes

daily

for7day


drootplaning

Feres et al.

148

Tab

le5.

(Con

tinued

)

Geo

grap

hic

Reg

ion/

Referen

ces

Duration

Placebo

(Yes/N

o)

Antibiotic/dose

Total

population/

no.o

fgroups

Age

(yea

rs)

No.o

fsm

oke

rsIn

itialm

ean

pro

bing

dep

th(m

m)

Disea

seAntibiotictherap

y(duration

andmomen

t)

Yek

etal.(22

1)6months

No

Metronidazole

500mg

Amoxicillin50

0mg

28/2

15–4

57

Just

per

catego

ries

ofsites

Agg

ressive

periodontitis

Threetimes

daily

for7day

sStartingat

thefirstscaling


Oteoet

al.

(152

)6months

Yes

Azithromycin

500mg

29/2

36–6

514

2.8–

2.9

Chronic

periodontitis

Once

daily

for7day


drootplaning

Baltacioglu

etal.(10

)2months

No

Metronidazole

250mg

Amoxicillin25

0mg

doxycycline10

0mg

38/3

18–4

015

4.9

Agg

ressive

periodontitis

Metronidazole,a

moxicillin,

threetimes

daily

for10

day

sDoxycycline,

once

daily

for

14day


drootplaning

Aim

ettiet

al.

(2)

6months

Yes

Metronidazole

500mg

Amoxicillin50

0mg

39/2

35.5

�2.9

04.3–

4.5

Agg

ressive

periodontitis

Threetimes

daily

for7day

sStartingat

thefirstscaling


Han

etal.(77

)6months

Yes

Azithromycin

500mg

28/2

35–5

413

3.8–

4.0

Chronic

periodontitis

Once

daily

for3day


drootplaning

Emingile

tal.

(34)

6months

Yes

Azithromycin

500mg

32/2

18–3

813

3.8–

4.1

Agg

ressive

periodontitis

Once

daily

for3day


drootplaning

Asia

Gomie

tal.

(47)

25wee

ksNo

Azithromycin

500mg

34/2

48.2

�11

.50

4.5

Chronic

periodontitis

Once

daily

for3day

sStartingbefore

scalingan

drootplaning


149

Tab

le5.

(Con

tinued

)

Geo

grap

hic

Reg

ion/

Referen

ces

Duration

Placebo

(Yes/N

o)

Antibiotic/dose

Total

population/

no.o

fgroups

Age

(yea

rs)

No.o

fsm

oke

rsIn

itialm

ean

pro

bing

dep

th(m

m)

Disea

seAntibiotictherap

y(duration

andmomen

t)

Moen

tagh

avi

etal.(14

1)8wee

ksYes

Metronidazole

250mg

Amoxicillin50

0mg

50/2

34.4

�8.2

05.6–

5.8

Chronic

periodontitis

Threetimes

daily

for7day

sStartingat

thefirstscaling


Yashim

aet

al.

(220

)1ye

arNo

Azithromycin

500mg

30/3

51�

12.6

05.1

Chronic

periodontitis

Once

daily

for3day

sStartingbefore

scalingan

drootplaning

Geo

grap

hic

Reg

ion/

Referen

ces

Treatmen

tPrincipal

clinical

findings

Principal

micro

biologica

lfindings

(method)

Test

Control

(b)Mainfindings

NorthAmerica

Feres

etal.(39

)Sc

alingan

drootplaning+

amoxicillin

scalingan

drootplaning+

metronidazole

–Nodifference

betwee

ngroupsin

full-

mouth

mea

nprobingdep

th(amoxicillin,

0.4mm;m

etronidazole,0

.6mm),an

dclinical

attach

men

tga

in(amoxicillin,

0.5mm;m

etronidazole,0

.3mm

(P>0.05

)at

1ye

ar

Leve

lsan

dproportionsofT

annerella

forsythia,P

orphyrom

onas

gingiva

lisan

dTrepon

emaden

ticola

werereduced

duringan

tibioticad

ministrationan

dwerelower

than

baselineleve

lsat

1ye

ar(P

<0.00

1).A

moxicillinlowered

the

proportionsofA

ctinom

yces

species

(checke

rboardDNA–D

NAhyb

ridization)

Masca

renhas

etal.(12

9)Sc

alingan

drootplaning+

azithromycin

Scalingan

droot

planing

Thetest

groupsh

owed

grea

termea

nprobingdep

threduction(azithromycin,

3.5mm;sca

lingan

drootplaning,

2.0mm),an

dclinical

attach

men

tga

in(azithromycin,2

.6mm;a

ndscalingan

drootplaning,

1.3mm

(P<0.05

)in

sites

withinitialP

D≥7mm

at6months

Therewas

a3.35

%an

d33

.32%

reduction

onBANA-positive

sites(six

sitesper

subject)forthescalingan

drootplaning

andazithromycin

groups,resp

ective

ly(P

<0.05

)(BANATest)

Haffajeeet

al.

(66,

72)

Scalingan

drootplaning +

azithromycin

Scalingan

drootplaning+

metronidazole

Scalingan

drootplaning+

sub-

antibac

terial

dose

doxycylin

e

Scalingan

droot

planing

Azithromycin

andmetronidazole

groups

showed

grea

termea

nprobingdep

threductionan

dclinical

attach

men

tga

inin

siteswithinitialp

robingdep

th≥7

mm

than

theother

groups(P

<0.05

)at

1ye

ar

Alltrea

tmen

tsreducedco

unts

ofred

complexsp

eciesat

1ye

ar.N

omajor

differencesweredetectedam

ong

trea

tmen

tgroupsat

1ye

ar(checke

rboard

DNA–D

NAhyb

ridization)

Feres et al.

150

Tab

le5.

(Con

tinued

)

Geo

grap

hic

Reg

ion/

Referen

ces

Treatmen

tPrincipal

clinical

findings

Principal

micro

biologica

lfindings

(method)

Test

Control

Dastooret

al.

(29)

Scalingan

drootplaning+

periodontal

surgery+

azithromycin

Scalingan

droot

planing+

periodontal

surgery+

placebo

Controlg

roupsh

owed

grea

termea

nprobingdep

threductionin

siteswith

initialp

robingdep

th≥7

mm

forthe

surgically

(azithromycin+periodontal

surgery,

2.8mm;p

eriodontalsurgery,

3.8mm,P

<0.05

)an

dnonsu

rgically

(azithromycin+periodontalsurgery,

2.0mm;p

eriodontalsurgery,

2.8mm,

P<0.05

)trea

tedsitesat

6months

Both

trea

tmen

tsreducedthemea

nBANA

scoresat

2wee

ksaftersu

rgery(0.80an

d0.77

forperiodontal

surgery+

azithromycin

andperiodontal

surgerygroups,resp

ective

ly).At

6months,BANAscoresin

both

groups

returned

tobaselineleve

ls(BANATest)

Goodsonet

al.

(50)

Scalingan

drootplaning+

loca

ltetracycline

delivery

Scalingan

drootplaning+

system

icmetronidazole+am

oxicillin

Scalingan

drootplaning+

system

icmetronidazole+am

oxicillin+loca

ltetrac

yclin

edelivery

Scalingan

drootplaning+

periodontal

surgery

Scalingan

drootplaning+

loca

ltetrac

yclin

edelivery+

periodontalsurgery

Scalingan

drootplaning+

system

icmetronidazole+am

oxicillin+periodontal

surgery

Scalingan

drootplaning+

system

icmetronidazole+am

oxicillin+loca

ltetrac

yclin

edelivery+

periodontalsurgery

Scalingan

droot

planing

Testgroupsreceiving

metronidazole+am

oxicillinsh

owed

0.5mm

more

mea

nprobingdep

threductionan

dclinical

attach

men

tga

in(P

<0.05

),than

controlg

roupat

2ye

ars

No

Euro

pe

Winke

letal.

(214

)Sc

alingan

droot

planing+

metronidazole+am

oxicillin

Scalingan

droot

planing+

placebo

Thetest

groupsh

owed

grea

termea

nprobingdep

threduction

(metronidazole+am

oxicillin,3

.2mm;

scalingan

drootplaning,

2.5mm),an

dclinical

attach

men

tga

in(m

etronidazole+am

oxicillin,2

.0mm;

scalingan

drootplaning,

1.5mm)

(P<0.05

)in

siteswithinitialP

D>7

mm

at6months

Nostatistica

llysign

ifica

ntdecreasewas

observed

inthenumber

ofsubjects

colonized

byan

yofthetested

speciesin

thescalingan

drootplaninggroup

(P>0.05

).In

the

metronidazole+am

oxicillingroupthe

number

ofsubjectsco

lonized

byP.

gingiva

lis,T.forsythia

andPrevo

tella

interm

edia

showed

asign

ifica

ntdecrease

at6months(P

<0.05

)(culture)


151

Tab

le5.

(Con

tinued

)

Geo

grap

hic

Reg

ion/

Referen

ces

Treatmen

tPrincipal

clinical

findings

Principal

micro

biologica

lfindings

(method)

Test

Control

Ram

berget

al.

(163

)Sc

alingan

drootplaning+

tetrac

yclin

eSc

alingan

droot

planing

Nodifference

betwee

ngroupsin

full-

mouth

mea

nprobingdep

th(tetracycline,

1.0�

0.8mm;sca

lingan

drootplaning,

0.7�

0.7mm)(P

>0.05

),an

dthetest

groupsh

owed

grea

termea

nclinical

attach

men

tga

in(tetracycline,

0.5�

0.6mm;sca

lingan

drootplaning,

0.2�

0.5mm)(P

<0.05

)at

1ye

ar.T

his

ben

efitwas

notmaintained

at3,

5an

d13

years

No

Sigu

schet

al.

(183

)Sc

alingan

drootplaning+

doxycycline

Scalingan

drootplaning+

metronidazole

Scalingan

drootplaning+

clindam

ycin

Scalingan

droot

planing

Metronidazole

andclindam

ycin

groups

showed

grea

termea

nprobingdep

threduction(4.8

mm

forboth

groups)

and

clinical

attach

men

tga

in(3.4

mm

and

2.9mm,respective

ly)in

siteswithinitial

probingdep

th≥7

mm

than

the

doxycycline(probingdep

threduction,

2.0mm;c

linical

attach

men

tga

in,

1.4mm)an

dco

ntrolg

roups(probing

dep

threduction,1

.2mm;c

linical

attach

men

tga

in,0

.5mm)(P

<0.05

)at

2ye

ars

Themea

nnumber

ofc

olon-form

ingunits

forP.g

ingiva

lisan

dActinob

acillus

actinom

ycetem

comitan

swas

reducedin

themetronidazole

andclindam

ycin

groups(P

<0.05

)at

2ye

ars

Smithet

al.

(192

)Sc

alingan

drootplaning+

azithromycin

Scalingan

droot

planing+

placebo

Thetest

groupsh

owed

grea

termea

nprobingdep

threductionin

siteswith

initialp

robingdep

th≥6

mm

andin

the

full-mouth

mea

nprobingdep

that

22wee

ks

No

Rooney

etal.

(170

)Sc

alingan

droot

planing+

amoxicillin+metronidazole

Scalingan

droot

planing+

metronidazole+placebo

Scalingan

droot

planing+

amoxicillin+placebo

Scalingan

droot

planing+

placebo

Thetest

groupsh

owed

betterclinical

resu

ltsthan

theco

ntrolg

roup.T

he

grea

test

improve

men

tin

mea

npercentage

ofsites

≥6mm

was

observed

intheam

oxicillin+metronidazole

group

at6months

Nostatistica

llysign

ifica

ntdifferenceswere

observed

amonggroupsat

6months

(P>0.05

)(C

ulture)

Feres et al.

152

Tab

le5.

(Con

tinued

)

Geo

grap

hic

Reg

ion/

Referen

ces

Treatmen

tPrincipal

clinical

findings

Principal

micro

biologica

lfindings

(method)

Test

Control

Ehmke

etal.

(33)

Scalingan

drootplaning+

metronidazole+

amoxicillin+ch

lorhexidine

Scalingan

droot

planing

Thetest

groupsh

owed

grea

termea

nclinical

attach

men

tga

inin

siteswith

initialp

robingdep

th≥7

mm

(metronidazole+am

oxicillin+

chlorhexidine,

1.7�

0.3mm;sca

lingan

drootplaning,

0.3�

0.3mm)(P

<0.05

)at

2ye

ars.

Thepreva

lence

ofA

.actinom

yceten

comitan

s(upto

18months)

andP.gingiva

lis(upto

3months)

werelower

andofE

iken

ella

corrod

ens(at10

day

s)werehigher

(P<0.05

)in

thetest

groupco

mpared

withtheco

ntrolg

roup.(PCRan

ddot-blot

hyb

ridization)

Guerrero

etal.

(59)

Full-mouth

scalingan

droot

planing+

metronidazole+am

oxicillin

Full-mouth

scalingan

drootplaning+

placebo

Thetest

groupsh

owed

grea

termea

nprobingdep

threduction

(metronidazole+am

oxicillin,3

.1mm;

scalingan

drootplaning,

1.8mm)an

dclinical

attach

men

tga

in(m

etronidazole+am

oxicillin,2

.3mm;

scalingan

drootplaning,

1.3�

0.6mm)

(P<0.05

)in

siteswithintial

PD

≥7mm

at6months.

No

Mombelie

tal.

(142

)Full-mouth

scalingan

droot

planing+

Emdoga

in+metronidazole+

amoxicillin

Full-mouth

scalingan

drootplaning+

Emdoga

in+placebo

Thetest

groupsh

owed

grea

termea

nprobingdep

threduction(sca

lingan

drootplaning+

Emdoga

in+metronidazole+

amoxicillin,3

.0�

2.1mm;sca

lingan

drootplaning+

Emdoga

in,1

.6�

1.4mm)

andclinical

attach

men

tga

in(m

etronidazole+am

oxicillin,

2.3�

3.5mm;E

mdoga

in,0

.4�

3.8mm)

(P<0.05

)at

1ye

ar

No

Xajigeo

rgiou

etal.(21

5)Sc

alingan

drootplaning+

metronidazole

Scalingan

drootplaning+

doxycycline

Scalingan

drootplaning+

metronidazole+Amoxicillin

Scalingan

droot

planing

Metronidazole+am

oxicillinan

dmetronidazole

groupssh

owed

grea

ter

reductionin

themea

nproportionofsites

withprobingdep

th≥7

mm

(80%

and

87.8%,respective

ly)than

theco

ntrol

group(sca

lingan

drootplaning,

57.7%)at

6months(P

<0.05

).Nodifferenceswere

observed

betwee

ndoxycyclinean

dco

ntrolg

roups(P

>0.05

)

Metronidazole+am

oxicillinwas

theonly

trea

tmen

tthat

causedareductionin

the

leve

lsofA

.actinom

ycetem

comitan

san

dofthethree‘red

complex’

speciesat

6months(P

<0.05

)(checke

rboardDNA–

DNAhyb

ridization)


153

Tab

le5.

(Con

tinued

)

Geo

grap

hic

Reg

ion/

Referen

ces

Treatmen

tPrincipal

clinical

findings

Principal

micro

biologica

lfindings

(method)

Test

Control

Cionca

etal.(18

,19

)Sc

alingan

droot

planing+

metronidazole+am

oxicillin

Scalingan

droot

planing+

placebo

Thetest

groupsh

owed

alower

mea

nnumber

ofsites

withprobingdep

th≥5

mm+bleed

ingonprobing(0.4

�0.8

sites)

than

theco

ntrolg

roup(3.0

�4.3

sites,P<0.05

)at

6months

Nodifferencesfortotalb

acterial

load

were

observed

betwee

ngroups(P

>0.05

).P.gingiva

lis,Fu

soba

cterium

nucleatum

spp.a

ndT.forsythia

counts

werelower

inthetest

groupthan

intheco

ntrol

(P<0.05

)at

6months(rea

l-timePCR)

Yek

etal.(22

1)Sc

alingan

droot

planing+

metronidazole+am

oxicillin

Scalingan

droot

planing

Thetest

groupsh

owed

grea

termea

nreductionin

themea

nproportionofsites

withprobingdep

th≥7

mm

(P<0.05

)at

6months

T.d

enticola

showed

astea

dydecreaseonly

inthetest

group.T

.forsythia

decreased

inboth

groups,butat

6monthsitwas

elim

inated

from

thesampledsitesonly

intest

group(PCR)

Oteoet

al.(15

2)Sc

alingan

drootplaning+

azithromycin

Scalingan

droot

planing+

placebo

Thetest

groupsh

owed

agrea

terreduction

infull-mouth

mea

nprobingdep

th(azithromycin,0

.80mm;sca

lingan

droot

planing,

0.34

mm)an

dclinical

attach

men

tga

in(azithromycin,0

.76mm;

andscalingan

drootplaning,

0.29

mm)

(P<0.05

)at

6months

Thefreq

uen

cyofd

etectionofP

.gingiva

lis

andT.forsythia

decreased

at6monthsin

thetest

group(P

<0.05

)(C

ulture)

Baltaciogluet

al.

(10)

Full-mouth

scalingan

droot

planing+

doxycycline

Full-mouth

scalingan

droot

planing+

metronidazole+am

oxicillin

Full-mouth

scalingan

drootplaning

Themetronidazole+am

oxicillingroup

showed

alower

mea

nproportionofsites

withprobingdep

th≥7

mm

(8.6

�4.0%

)than

thedoxycycline(13.6�

6.8%

)an

dco

ntrolg

roups(sca

lingan

drootplaning,

22.2

�6.5%

)at

2months(P

<0.05

).Mea

nprobingdep

than

dclinical

attach

men

tleve

lweresign

ifica

ntlylower

inthemetronidazole+am

oxicillingroup

(3.3

�0.4mm)than

thedoxycycline

(3.9

�0.3mm)an

dco

ntrolg

roups

(4.2

�0.2mm)at

2months(P

<0.05

)

No

Feres et al.

154

Tab

le5.

(Con

tinued

)

Geo

grap

hic

Reg

ion/

Referen

ces

Treatmen

tPrincipal

clinical

findings

Principal

micro

biologica

lfindings

(method)

Test

Control

Aim

ettiet

al.(2)

Onesessionoffull-mouth

scalingan

droot

planing+

metronidazole+am

oxicillin

Onesessionoffull-

mouth

scalingan

drootplaning+

placebo

Thetest

groupsh

owed

agrea

termea

nprobingdep

threduction(m

etronidazole+

amoxicillin,3

.1�

0.6mm;sca

lingan

drootplaning,

2.4�

0.7mm)an

dclinical

attach

men

tga

in(m

etronidazole+

amoxicillin,3

.0�

0.7mm;sca

lingan

drootplaning,

2.0�

0.8mm)(P

<0.05

)in

siteswithintial

PD

≥7mm

at6months.

Themea

npercentage

ofsites

with

probingdep

th≥5

mm

was

lower

inthe

test

group(17.7%

)than

theco

ntrolg

roup

(28.4%

)at

6months(P

<0.05

)

Thetest

groupsh

owed

lower

preva

lences

ofA

.actinom

ycetem

comitan

s,T.

den

ticola,a

ndT.forsythia

compared

with

theco

ntrolg

roup(P

<0.05

)at

6months

(PCR)

Han

etal.(77

)Sc

alingan

drootplaning+

azithromycin

Scalingan

droot

planing+

placebo

Nodifference

betwee

ngroupsin

mea

nprobingdep

threduction(azithromycin,

4.9�

1.1mm;sca

lingan

drootplaning,

4.5�

0.5mm)an

dclinical

attach

men

tga

in(azithromycin,2

.3�

3.1mm;

scalingan

drootplaning,

0.6�

0.5mm)

(P>0.05

)in

siteswithinitialP

D≥7

mm

at6months

Both

groupssh

owed

simila

rmea

nreductionin

leve

lsofA

.actinom

ycetem

comitan

s,P.gingiva

lis,

T.forsythia

,P.interm

edia

and

F.nucleatum

at6moths( P

>0.05

)(rea

l-timePCR)

Emingile

tal.

(34)

Scalingan

drootplaning+

azithromycin

Scalingan

droot

planing+

placebo

Nodifference

betwee

ngroupsin

mea

nprobingdep

threductionan

dclinical

attach

men

tga

in(P

>0.05

)in

siteswith

initialP

D≥7

mm

at6months

Both

groupssh

owed

simila

rleve

lsofP

.gingiva

lis,P.interm

edia,F

.nucleatum,T

.forsythia,a

ndtotalb

acterial

counts

at6months(P

>0.05

)(rea

l-timePCR)

Asia

Gomie

tal.(47

)Full-mouth

scalingan

droot

planing+

azithromycin

Scalingan

droot

planing

Thetest

groupsh

owed

lower

mea

nprobingdep

th(2.4

�0.8mm)than

the

controlg

roup(3.3

�0.4mm)(P

<0.05

)an

dnodifference

was

observed

betwee

ngroupsin

mea

nclinical

attach

men

tleve

l(azithromycin,4

.8�

1.0mm;sca

lingan

drootplaning,

5.7�

1.0mm)(P

>0.05

)at

25wee

ks

‘Red

complex’

species,P.interm

edia,A

.actinom

ycetem

comitan

san

dPrevo

tella

nigrescen

swerenotdetectedin

thetest

groupuntil1

3wee

ks.Intheco

ntrol

group,P

.gingiva

lis,T.forsythia

and

P.interm

edia

weredetectedafter

5wee

ks(PCR)


155

≥5 mm at baseline (mean of 43.9 sites). At 1 yearpost-treatment, only 18.2% of subjects receiving scal-ing and root planing alone had reached the clinicalendpoint for treatment (i.e. low-risk profile for furtherdisease progression) compared with 57.7% in themetronidazole group and 63% in the metronidazole +amoxicillin group. On the other hand, 67.3% of thesubjects in the control group still had at least ninesites with probing depth ≥5 mm at 1 year (i.e. a high-risk profile for further disease progression) comparedwith 33.4% and 18% in the metronidazole and metro-nidazole + amoxicillin groups, respectively. The per-centage of subjects presenting residual sites withprobing depth ≥ 6 mm was also a relevant finding.Even though all subjects included in this analysis hadsix or more of these deep sites at baseline (average of25.2 sites), 51.8% of subjects who received adjunctivemetronidazole + amoxicillin did not harbor any sitewith probing depth ≥6 mm at 1 year compared withonly 14.5% in the control group. This is an importantpiece of information because it has been suggestedthat the presence of even one site with probing depth≥6 mm after periodontal treatment may increase therisk for future disease progression (132). The data forresidual sites clearly showed a benefit of the use ofboth antibiotic protocols, with a nonsignificant trendtowards greater additional benefits when the twodrugs were combined. This trend was confirmedwhen the changes in probing depth and in clinicalattachment level from baseline to the follow-upappointments were evaluated. A statistically signifi-cant benefit for metronidazole + amoxicillin overmetronidazole alone was observed for probing depthreduction and clinical attachment gain in initiallyintermediate sites (Table 8). These data suggest thatthe adjunctive use of these systemic antibiotics, espe-cially metronidazole + amoxicillin, may benefit deep,as well as intermediate pockets.

In accordance with the clinical changes, there weremarked differences among treatments in changingthe subgingival microbial composition. The evalua-tion of the bacterial counts over the course of thestudy presented in Fig. 4 shows that more specieswere statistically significantly affected when the twoantibiotics were combined, in comparison with scal-ing and root planing alone or with metronidazole.The treatments were effective in reducing the levelsof all three species from the red complex. However,subjects receiving one of the antibiotic protocols hadsignificantly lower levels of these pathogens at 1 year,as well as of four putative pathogens from the orangecomplex: F. nucleatum ssp. polymorphum, F. nuclea-tum ssp. vincentii, P. intermedia and E. nodatum.T

able

5.(C

ontinued

)

Geo

grap

hic

Reg

ion/

Referen

ces

Treatmen

tPrincipal

clinical

findings

Principal

micro

biologica

lfindings

(method)

Test

Control

Moen

tagh

avi

etal.(14

1)Full-mouth

scalingan

droot

planing+

metronidazole+am

oxicillin

Full-mouth

scalingan

drootplaning+

placebo

Thetest

groupsh

owed

grea

termea

nprobingdep

threduction

(metronidazole+am

oxicillin,2

.2mm;

scalingan

drootplaning,

1.5mm)an

dclinical

attach

men

tga

in(m

etronidazole+am

oxicillin,1

.9mm;

scalingan

drootplaning,

1.2mm)

(P<0.05

)in

siteswithinitialP

D≥5mm

at2months

Only

thetest

groupsh

owed

areductionin

theleve

lsofA

.actinom

ycetem

comitan

san

dP.gingiva

lis(P

<0.05

).P.interm

edia

was

reducedin

both

groups(P

<0.05

)at

2months(C

ulture)

Yashim

aet

al.

(220

)Full-mouth

scalingan

droot

planing+

azithromycin

Partial-m

outh

scalingan

droot

planing+

azithromycin

Scalingan

droot

planing

Both

test

groupssh

owed

grea

ter

improve

men

tsin

mea

nprobingdep

than

dclinical

attach

men

tleve

lthan

the

controlg

roup(P

<0.05

)at

1ye

ar.N

odifferenceswereobserved

betwee

ntest

groups(P

>0.05

)

Periodontalp

athoge

nswerereducedin

both

test

groupsim

med

iately

after

trea

tmen

t.They

tended

toincrea

segrad

ually

intheco

ntrolg

roupat

1ye

ar(rea

ltim

ePCR)

Feres et al.

156

Table 6. Number of sites with probing depth ≥5, ≥6 and ≥7 mm at baseline and at 3 months, 6 months and 1-yearpost-treatment as well as changes in number of sites with probing depth ≥5 mm between baseline and 1 year post-treatment, in 154 subjects with advanced periodontitis treated with scaling and root planing alone, with scaling androot planing combined with metronidazole or with scaling and root planing combined with metronidazole + amoxicil-lin

Probingdepth

Time point Treatment groups P*

Scaling and rootplaning (n = 55)

Scaling androot planing +metronidazole(n = 45)

Scaling and rootplaning + metronidazole +amoxicillin (n = 54)

≥5 mm Baseline 43.9 � 20.5a 37.1 � 19.5a 42.4 � 22.3a 0.244

3 months 18.4 � 17.4A,b 10.7 � 12.2B,b 8.8 � 11.6B,b 0.001

6 months 16.6 � 15.5A,b 9.6 � 11.7B,b 6.4 � 7.6B,b 0.000

1 year 18.0 � 15.3A,b 8.0 � 11.2B,b 5.3 � 6.3B,b 0.000

D 0–1 year 25.8 � 15.7A 29.0 � 16.6 37.1 � 18.8B 0.002

≥6 mm Baseline 24.0 � 17.4a 20.7 � 16.1a 25.2 � 20.9a 0.436

3 months 8.8 � 11.3A,b 4.0 � 7.4B,b 3.1 � 6.7B,b 0.001

6 months 8.0 � 10.8A,b 4.1 � 8.1B,b 2.3 � 4.3B,b 0.001

1 year 7.7 � 10.5A,b 3.4 � 6.7B,b 1.8 � 3.4B,b 0.000

≥7 mm Baseline 13.0 � 13.8a 9.8 � 11.5a 14.6 � 18.3a 0.335

3 months 4.6 � 7.7A,b 1.9 � 4.3B,b 1.5 � 4.4B,b 0.012

6 months 4.0 � 7.2A,b 1.6 � 4.6B,b 1.1 � 3.0B,b 0.012

1 year 3.8 � 7.1A,b 1.2 � 4.0B,b 0.9 � 2.7B,b 0.005

Values are given as mean � SD. The significance of differences among time points was determined using repeated-measures analysis of variance and Tukey’s multi-ple comparison test (different lower-case letters indicate significant differences between time points). *The significance of differences among groups at each timepoint was assessed using the one-way analysis of variance and Tukey’s multiple comparison tests (different capital letters indicate significant differences betweenpairs of groups).

Table 7. Assessment of the risk of disease progression according to Lang & Tonetti (105) *, as well as the percentage ofsubjects with no, one or two, or three or more sites with probing depth ≥6 mm and ≥7 mm at 1 year post-treatment,in 154 subjects with advanced periodontitis treated with scaling and root planing alone, scaling and root planing com-bined with metronidazole, or scaling and root planing combined with metronidazole + amoxicillin

Variables Categories Treatment groups P†

Scaling androot planing(n = 55)


Scaling androot planing +metronidazole +amoxicillin (n = 54)

Risk for diseaseprogression

Low risk 18.2 57.7 63.0 <0.000

Moderate risk 14.5 8.9 13.0

High risk 67.3 33.4 18.0

Probingdepth ≥6 mm

0 14.5 44.4 51.8 <0.000

1–2 69.0 26.6 24.0

≥3 14.5 29.0 24.2

Probingdepth ≥7 mm

0 36.4 68.8 72.2 0.000

1–2 25.5 20.0 16.6

≥3 38.1 11.2 11.2

Values are given as percentage of subjects. *Low risk, presence of at most four sites with probing depth ≥5 mm (the clinical endpoint of treatment); moderate risk,presence of five to eight sites with probing depth ≥5 mm; high risk, presence of nine or more sites with probing depth ≥5 mm. †The significance of differences amonggroups was assessed using the chi-square test.


157

Figure 5 demonstrates that the overall proportions ofthe complexes harboring pathogens decreased, andthe overall proportions of those harboring beneficialspecies increased, over the course of the study in alltreatment groups. However, at 1 year, subjects takingantibiotics had lower mean proportions of red andorange complexes in comparison with those receivingscaling and root planing only, whereas those subjectstaking metronidazole + amoxicillin had an additionalbenefit, which was higher proportions of Actinomycesspecies in comparison with the other two treatments.The microbial endpoint for treatment was achievedby 32%, 60% and 71% of the subjects in the scalingand root planing, metronidazole and metronida-zole+amoxicillin groups, respectively.

As stated in the first section of this article, theadvantage of one anti-infective therapy over anotheris most probably related to their capabilities of chang-ing the complex and pathogenic microbial ecology ofthe oral cavity in the presence of periodontal infec-tion. This assumption was nicely elucidated by thedata presented in this subitem, in which a markedclinical benefit from both antibiotic protocols wasobserved compared with those obtained with scalingand root planing alone. Moreover, these clinical ben-efits were accompanied by a more beneficial change

in the microbial profile, including a greater reductionin the proportions of pathogens and an increase inhost-compatible species. In addition, the slight supe-riority of metronidazole + amoxicillin over metroni-dazole alone was probably a result of the moreprofound effect of the combination of the two drugsin increasing proportions of the beneficial Actinomy-ces species.

Azithromycin, a wide-spectrum bacteriostatic mac-rolide, emerged as a promising drug in medicine inthe early 1990s (9, 89, 178) and more recently in den-tistry (60, 61, 72, 129, 152, 220). Azithromycin presentsgood pharmacological properties, such as rapidabsorption, high tissue concentration (89) and longhalf-life (45, 46), allowing once-daily dosing (500 mg)for 3–6 days (86). This simple prescription protocoland the low incidence of side effects associated withthe use of azithromycin tends to reduce issues relatedto patient compliance, which is considered a majorproblem of several antibiotic protocols, such as met-ronidazole and metronidazole + amoxicillin, whichrequire the intake of three or six tablets a day for 7–14 days (42, 59). However, the results of the few ran-domized clinical trials that have evaluated the effectsof azithromycin in periodontal treatment are some-how controversial (29, 34, 47, 60, 72, 77, 129, 152, 177,

Table 8. Changes in probing depth and in clinical attachment between baseline and 3 months, baseline and 6 monthsand baseline and 1 year post-treatment in 154 subjects with advanced periodontitis treated with scaling and root plan-ing alone, scaling and root planing combined with metronidazole, or scaling and root planing combined with metroni-dazole + amoxicillin

Baselineprobing depth

Variables Time period Treatment groups P*




4–6 mm Probing depthreduction (mm)

0–3 months 1.2 � 0.4A 1.5 � 0.5B 1.8 � 0.5C 0.000

0–6 months 1.3 � 0.5A 1.6 � 0.5B 1.9 � 0.5C 0.000

0–1 year 1.3 � 0.5A 1.7 � 0.5B 2.0 � 0.4C 0.000

Clinical attachmentgain (mm)

0–3 months 1.0 � 0.5A 1.2 � 0.5B 1.5 � 0.4C 0.000

0–6 months 1.1 � 0.4A 1.3 � 0.5B 1.6 � 0.4C 0.000

0–1 year 1.1 � 0.5A 1.4 � 0.5B 1.7 � 0.4C 0.000

≥7 mm Probing depthreduction (mm)

0–3 months 2.6 � 1.0A 3.2 � 0.9B 3.8 � 0.9C 0.000

0–6 months 2.9 � 1.2A 3.5 � 1.0B 3.9 � 1.0C 0.000

0–1 year 3.0 � 1.3A 3.8 � 0.9B 4.0 � 1.0B 0.000


0–3 months 2.0 � 0.9A 2.6 � 1.1B 3.0 � 0.7B 0.000

0–6 months 2.3 � 1.0A 2.8 � 1.1B 3.3 � 0.9B 0.000

0–1 year 2.5 � 1.1A 3.1 � 1.1B 3.3 � 0.9B 0.000

Values are given as mean � SD. *The significance of differences among groups at each time point was assessed using one-way analysis of variance and Tukey’s mul-tiple comparison tests (different letters indicate significant differences between pairs of groups).

Feres et al.

158

192, 220). Although some authors demonstratedcertain benefits when azithromycin was used as anadjunct to mechanical debridement in the treatmentof aggressive periodontitis (60), smokers (129) or incases of mild/moderate chronic periodontitis (72,152, 192), others could not show a benefit (34, 77,177). In the light of this literature and of the data pre-sented in Tables 6–8 and Figs 4 and 5 on the benefi-cial effects of metronidazole or metronidazole +amoxicillin in the treatment of advanced periodonti-tis, the question that arises is whether azithromycinwould achieve the same outcomes as either one ofthese two antibiotic protocols. Taking into consider-ation that the benefits of the adjunctive metronida-zole + amoxicillin were somewhat superior to thoseobserved with metronidazole only (42, 130, 184)(Tables 6–8 and Fig. 4) and that the side effects donot differ significantly between these two drug proto-

cols (42), we decided to make a direct comparisonbetween the effects of azithromycin and metronida-zole + amoxicillin in the treatment of nonsmoker sub-jects with advanced chronic periodontitis bycompiling the data from three randomized clinicaltrials (42, 177, 184). It should be pointed out that thesubjects included in the study by Sampaio et al. (177)presented very advanced disease, and thus, in orderto provide the best comparison possible, we selectedsubjects with a similar disease pattern from the twoother studies (42, 184) by using a cut-off point of the‘presence of at least 25 sites with probing depth≥5 mm’ at baseline. The results of this analysis arepresented in Tables 9 and 10 and Figs 6 and 7. Azi-thromycin was given at a dose of 500 mg a day for5 days and metronidazole and amoxicillin were giventhree times daily for 14 days, at a dose of 400 mg and500 mg, respectively. They received clinical and

0.0 9.2 18.3 27.5 36.6

*** **

**

***

***

******

*****

******

******

**

*

SRP


A.naeslundii A.oris






C.gracilis C.rectus

C.showae E.nodatum






L.buccalis P.acnes


S.anginosus S.noxia

T.socranskii

0.0 9.2 18.3 27.5 36.6

*****

******

***

*****

***

******

***

*

SRP+MTZ

0.0 9.2 18.3 27.5 36.6

***

****

**

**

***

***

******

******

*****

******

*****

********

******

**

SRP+MTZ+AMX

Counts x 105

Actinomyces

Purple

Yellow

Green

Orange

Red

Others

0.0 9.2 18.3 27.5 36.6

1 year

Baseline

3 months

6 months

1 year

SRPSRP+MTZ

SRP+MTZ+AMXAAB

ABBB B A

ABB

B BB B

B B A

AA

Fig. 4. Profiles of the mean counts (3105) of 40 taxa insubgingival biofilm samples taken from subjects withadvanced periodontitis treated with scaling and root plan-ing (SRP), alone (n = 55), combined with 400 mg of metro-nidazole (three times daily for 14 days) (SRP+MTZ)(n = 45) or combined with 400 mg of metronidazole +500 mg of amoxicillin (three times daily for 14 days)(SRP+MTZ+AMX) (n = 54), at baseline, and at 3 months,6 months and 1 year post-treatment. The panel at the farright of the figure superimposes the microbial profiles at1 year to permit easier comparison among groups. Ninesubgingival biofilm samples were taken from each subjectat each time point and were analyzed separately to deter-

mine their content of 40 species of bacteria. The specieswere ordered and grouped according to the microbialcomplexes described by Socransky et al. (193). The meanvalues for each species were averaged within a subject andthen across subjects in each group at each time point. Thesignificance of differences among time points was deter-mined using the Friedman test adjusted for multiple com-parisons [Socransky et al. (199)] (*P < 0.05; **P < 0.01;***P < 0.001). The significance of differences amonggroups at 1 year post-treatment was determined usingKruskal–Wallis and Dunn’s multiple comparison tests (dif-ferent letters indicate significant differences between pairsof groups, P < 0.05).


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microbiological monitoring and periodontal mainte-nance at 3 and 6 months as well as at 1 year post-treatment. The mean baseline probing depth andclinical attachment level was, respectively, 4.8 mmand 5.3 mm for the scaling and root planing group,4.7 mm and 5.3 mm for the azithromycin group and4.7 mm and 5.1 mm for the metronidazole + amoxi-cillin group. No statistically significant differenceswere observed among groups at baseline for any clini-cal parameter (P > 0.05, data not shown). As men-tioned above, the subjects selected for this analysispresented very advanced periodontitis, as indicatedby the high mean probing depth values and the highnumber of initially deep sites presented in Table 9. Asa result of this specific clinical profile, the mean num-ber of sites with probing depth ≥5 mm in these sub-jects was much higher (approximately 60 sites) thanthat observed in subjects from the previous analysis(approximately 40 sites) (Table 6). This is probablywhy only a few subjects reached the clinical endpointfor treatment in this analysis: 0%, 12.3% and 20%, inthe scaling and root planing, azithromycin and met-ronidazole + amoxicillin groups, respectively. At

1 year post-treatment, subjects treated with scalingand root planing only presented a much higher meannumber of sites with probing depth ≥5 mm (n = 29)than did those treated with adjunctive metronida-zole+amoxicillin (n = 9.6; P < 0.05). The mean num-ber of these residual sites for subjects who tookazithromycin remained in between (n = 19.1), but didnot differ significantly from the numbers in the othertwo groups (P > 0.05). These results indicate anadvantage of treatment with metronidazole + amoxi-cillin over treatment with azithromycin, which wasreinforced by the data presented in Table 10 forchanges from baseline to 1 year in probing depth andclinical attachment in initially intermediate and deepsites. Here again, only the metronidazole + amoxicil-lin-treated group showed statistically significantlygreater reduction in probing depth and gain in clini-cal attachment than the group treated with scalingand root planing only. There was very good agree-ment between the microbiological and clinicalresults. Figure 6 shows that the adjunctive use ofmetronidazole+amoxicillin resulted in a more pro-found beneficial change in the subgingival microbial

Fig. 5. Cumulative mean proportions of microbial com-plexes, as well as pie charts describing the mean propor-tion of microbial complexes at 1 year post-treatment insubgingival biofilm samples taken from subjects withadvanced periodontitis treated with scaling and rootplaning (SRP), alone (n = 55), combined with 400 mg ofmetronidazole (three times daily for 14 days) (SRP+MTZ)(n = 45) or combined with 400 mg of metronidazole +500 mg of amoxicillin (three times daily for 14 days)(SRP+MTX+AMX) (n = 54), at baseline and at 3 months, 6months and 1 year post-treatment. Nine subgingival bio-film samples were taken from each subject at each timepoint and were analyzed separately to determine theircontent of the 40 species of bacteria listed in Fig. 4. Thepercentage of DNA probe counts for each species was

determined at each site, then averaged within a subjectand then across subjects in each group at each timepoint. The mean proportion of each species was summedin order to determine the proportion of each complex.The colors represent the different complexes described bySocransky et al. (193). The grey color (‘Others’) repre-sents species that did not fall into any complex, and Acti-nomyces spp. are represented in blue. The significance ofdifferences among time points was determined usingrepeated-measures analysis of variance (***P < 0.001).The significance of differences among groups at 1 yearpost-treatment was determined using one-way analysis ofvariance and Tukey’s multiple comparison tests (differentletters indicate significant differences between pairs ofgroups, P < 0.05).

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Table 9. Number of sites with probing depth ≥5, ≥6 and ≥7 mm at baseline and at 3 months, 6 months and 1-yearpost-treatment as well as changes in number of sites with probing depth ≥5 mm between baseline and 1 year post-treatment, in 45 subjects with very advanced periodontitis treated with scaling and root planing alone, scaling and rootplaning combined with azithromycin, or scaling and root planing combined with metronidazole + amoxicillin

Probingdepth



Scaling and rootplaning + azithromycin(n = 15)

Scaling and root planing +metronidazole +amoxicillin (n = 15)

≥5 mm Baseline 63.4 � 23.3a 60.2 � 25.4a 59.8 � 19.8a 0.191

3 months 33.8 � 26.3A,b 14.5 � 7.5B,b 12.1 � 11.4B,b 0.005

6 months 28.4 � 22.2A,b 15.9 � 11.1b 11.2 � 8.0B,b 0.013

1 year 29.0 � 21.0A,b 19.1 � 15.3b 9.6 � 6.4B,b 0.005

D 0–1 year 34.4 � 18.3A 41.1 � 21.1 50.2 � 18.5B 0.044

≥6 mm Baseline 48.4 � 22.0a 42.9 � 22.9a 43.4 � 16.7a 0.547

3 months 17.8 � 16.5A,b 4.2 � 3.6B 4.7 � 9.6B,b 0.004

6 months 15.0 � 15.4A,b 5.4 � 5.5B 4.2 � 6.1B,b 0.014

1 year 13.4 � 15.6b 6.9 � 7.5b 4.2 � 4.8b 0.054

≥7 mm Baseline 32.8 � 17.2a 25.5 � 16.4a 29.2 � 14.6a 0.467

3 months 8.6 � 10.0A,b 1.6 � 2.5B,b 1.8 � 7.46B,b 0.036

6 months 7.2 � 9.1b 1.9 � 2.6b 1.9 � 5.0b 0.057

1 year 6.0 � 8.7b 2.0 � 3.3b 2.5 � 4.7b 0.162

Values are given as mean � SD. *The significance of differences among time points was determined using repeated-measures analysis of variance and Tukey’s multiplecomparison test (different lower-case letters indicate significant differences between time points). The significance of differences among groups at each time point wasassessed using the one-way analysis of variance and Tukey’s multiple comparison tests (different capital letters indicate significant differences between pairs of groups).

Table 10. Changes in probing depth and clinical attachment between baseline and 3 months, baseline and 6 monthsand baseline and 1 year post-treatment in 45 subjects with very advanced periodontitis treated with scaling and rootplaning alone, scaling and root planing combined with azithromycin, or scaling and root planing combined with met-ronidazole + amoxicillin




Scaling androot planing +azithromycin(n = 15)



0–3 months 1.3 � 0.5A 1.7 � 0.3 1.8 � 0.5B 0.024

0–6 months 1.5 � 0.4A 1.6 � 0.3 1.9 � 0.5B 0.026

0–1 year 1.5 � 0.5A 1.5 � 0.4A 2.1 � 0.4B 0.002


0–3 months 0.9 � 0.3A 1.2 � 0.3 1.4 � 0.5B 0.002

0–6 months 1.0 � 0.3A 1.2 � 0.4 1.5 � 0.4B 0.001

0–1 year 1.1 � 0.6A 1.1 � 0.4A 1.8 � 0.5B 0.001


0–3 months 2.5 � 0.7A 3.4 � 0.6B 3.9 � 0.7B 0.000

0–6 months 2.8 � 0.8A 3.4 � 0.5 4.3 � 0.8B 0.000

0–1 year 2.9 � 0.8A 3.3 � 0.9 4.4 � 0.7B 0.000


0–3 months 1.5 � 0.7A 2.5 � 0.6C 3.0 � 0.5B 0.000

0–6 months 1.8 � 0.6A 2.5 � 0.6C 3.4 � 0.7B 0.000

0–1 year 2.0 � 1.2A 2.6 � 0.8 3.5 � 0.6B 0.000

Values are given as mean � SD. *The significance of differences among groups at each time point was assessed using one-way analysis of variance and Tukey’s mul-tiple comparison tests (different letters indicate significant differences between pairs of groups).


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profile than that of azithromycin. It may be observedthat scaling and root planing + metronidazole +amoxicillin was the only treatment that significantlyreduced the proportions of the three pathogens of thered complex. Moreover, this treatment was able toincrease the proportions of three beneficial bacterialspecies (Actinomyces gerencseriae, A. naeslundii andStreptococcus sanguinis as opposed to only one in theazithromycin group (A. naeslundii). Even though scal-ing and root planing also led to the increase of somehost-compatible species, these changes were not sta-tistically significant from baseline to 1 year in thisgroup. Figure 7 shows the changes that occurred inthe microbial complexes with the use of the differenttreatments. All three treatments caused a beneficialchange in the microbial profile; however, one impor-tant aspect to point out in this figure is the residual

mean proportion of red complex in the three groups.These species accounted for approximately 12% ofthe 40 species evaluated in the scaling and rootplaning and azithromycin groups, and for 4.9% inthe metronidazole + amoxicillin group. Previouspublications have demonstrated a mean of 10%remaining red complex in subjects with advancedperiodontitis treated by scaling and root planing, butthis proportion is noticeably lower (3–3.5%) when sys-temic antibiotics are used as adjunct to the mechani-cal treatment (130, 138, 184). Therefore, 12%remaining mean proportions of red complex in theazithromycin-treated subjects was a ratherdisappointing result and is probably one of the majorreasons for the lack of an additional clinical effect ofazithromycin over that obtained with scaling and rootplaning only, as recently highlighted by Sampaio

0.0 4.6 9.1 13.7 18.3

***

SRP

0.0 4.6 9.1 13.7 18.3

**

**

*****

SRP+AZT

0.0 4.6 9.1 13.7 18.3

*

**

**

**

******

***

A.gerencseriaeA.israelii

A.naeslundiiA.oris

A.odontolyticusV.parvullaS.gordonii

S.intermediusS.mitis

S.oralisS.sanguinis

A. actinomycetemcomitansC.gingivalisC.ochracea

C.sputigenaE.corrodens

C.gracilisC.rectus

C.showaeE.nodatum

F.nucleatum.ssp.nucleatumF.nucleatum.ssp.polymorphum

F.nucleatum.ssp.vincentiiF.periodonticum

P.micraP.intermediaP.nigrescens

S.constellatusT.forsythia

P.gingivalisT.denticola

E.saburreumG.morbillorum

L.buccalisP.acnes

P.melaninogenicaN.mucosa

S.anginosusS.noxia

T.socranskii

SRP+MTZ+AMX

DNA probe counts (%)

Actinos

Purple

Yellow

Green

Orange

Red

Others

Baseline6 months

1 year

Fig. 6. Profiles of the mean proportions (%) of 40 taxa insubgingival biofilm samples taken from subjects with veryadvanced periodontitis treated with scaling and rootplaning (SRP) alone (n = 15), combined with 500 mg ofazithromycin (once a day for 5 days) (SRP+AZT)(n = 15) or combined with 400 mg of metronida-zole + 500 mg of amoxicillin (three times daily for 14 days)(SRP+MTX+AMX) (n = 15), at baseline, and at 6 monthsand 1 year post-treatment. Nine subgingival biofilm sam-ples were taken from each subject at each time point and

were analyzed separately to determine their content of 40species of bacteria. The species were ordered and groupedaccording to the microbial complexes described by Socran-sky et al. (193). The percentage of DNA probe counts foreach species was determined at each site, then averagedwithin a subject and then across subjects in each group ateach time point. The significance of differences amongtime points was determined using the Friedman testadjusted for multiple comparisons [Socransky et al. (199)](*P < 0.05; **P < 0.01; ***P < 0.001).

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et al. (177). The microbial endpoint for treatment wasachieved by 20%, 33.3% and 66.6% of the subjects inthe scaling and root planing, azithromycin and met-ronidazole+amoxicillin groups, respectively. Theseresults indicate that azithromycin does not yield thesame benefits of metronidazole + amoxicillin in thetreatment of advanced chronic periodontitis. In fact,the adjunctive use of this drug did not offer statisti-cally significant advantages in comparison with scal-ing and root planing only for this group of nonsmokersubjects with very advanced chronic periodontitis.However, as some studies have reported modest ben-efits with the use of azithromycin in smokers (129),mild/moderate chronic periodontitis (72, 152) andaggressive periodontitis (60), future studies using azi-thromycin for the treatment of these groups of sub-jects could be justified. Nevertheless, it should beemphasized that the results of the only clinical trialthat has directly compared the effects of azithromycinand metronidazole in subjects with mild/moderatechronic periodontitis were not very encouraging (72).The authors detected a statistically significant clinicaladvantage for metronidazole plus scaling and rootplaning in comparison with scaling and root planingonly, but not for azithromycin plus scaling and root

planing. In summary, despite the good pharmacologi-cal properties and its easy dosage regimen, at thispoint azithromycin does not seem to feature amongthe promising drugs for the treatment of periodontalinfections. This might be related to the fact that azi-thromycin is a bacteriostatic drug, as opposed to met-ronidazole and amoxicillin, which are bactericidal. Asmentioned at the start of this article, good and sus-tained clinical effects from treatments require a veryrapid and massive reduction of the total bacterial lev-els, especially of the strictly anaerobic pathogens, inorder to allow the best possible recolonization withhost-compatible species (71, 208). This goal is proba-bly more difficult to achieve with bacteriostatic drugssuch as azithromycin, other macrolides and tetracy-clines.

Collectively, the data outlined in this subitem sug-gest that subjects with advanced or very advancedperiodontitis would significantly benefit from theadjunctive use of metronidazole or metronidazole +amoxicillin. The most important advantage of thesetwo antibiotic protocols over scaling and root plan-ing, alone or combined with azithromycin, was thestatistically significant lower mean number/percent-age of sites and of subjects with probing depth

Fig. 7. Pie charts describing the mean proportions ofmicrobial complexes in subgingival biofilm samples takenfrom subjects with very advanced periodontitis treated withscaling and root planing (SRP), alone (n = 15), combinedwith 500 mg of azithromycin (SRP + AZT) (once a day for5 days, n = 15) or combined with 400 mg of metronida-zole + 500 mg of amoxicillin (three times daily for 14 days)(SRP + MTZ + AMX) (n = 15), at baseline and 1 year post-treatment. Nine subgingival biofilm samples were takenfrom each subject at each time point and were analyzedseparately to determine their content of the 40 species ofbacteria listed in Fig. 6. The percentage of DNA probecounts for each species was determined at each site, then

averaged within a subject and then across subjects in eachgroup at each time point. The mean proportion of each spe-cies was summed in order to determine the proportion ofeach complex. The colors represent the different complexesdescribed by Socransky et al. (193). The grey color repre-sents species that did not fall into any complex, and Actino-myces spp. are represented in blue. The significance ofdifferences between time points was determined using theWilcoxon test (*P < 0.05). The significance of differencesamong groups at baseline and at 1 year post-treatment wasdetermined using Kruskal–Wallis and Dunn’s multiplecomparison tests (different letters indicate significant dif-ferences between pairs of groups, P < 0.05).


163

≥5 mm up to 1 year after treatment. These resultshave direct clinical implications because they indicatea reduced need for periodontal surgery in subjectsreceiving one of these antibiotic protocols, as previ-ously suggested by Loesche and coworkers (115, 116).Moreover, subjects taking adjunctive metronidazole +amoxicillin exhibited some clinical and microbiologi-cal benefits compared with those achieved with met-ronidazole only, and the frequency of adverse eventsdid not differ significantly between the two treat-ments.

It is also important to realize that certain periodon-tal conditions, such as refractory (21) or apical peri-odontitis (205), and periodontal destruction inimmunocompromised patients (188), have been asso-ciated with superinfecting or nonoral microorganismsthat might not respond well to metronidazole andamoxicillin. This would be the case for beta-lactam-ase-producing Staphylococcus aureus (25, 93), someenteric gram-negative rods, Pseudomonas species andCandida albicans (27, 188). In this context, someauthors have suggested that the combination of met-ronidazole and ciprofloxacin could be effective in thetreatment of periodontitis associated with entericrods and Pseudomonas (186, 191), and in theory thistreatment could also be useful in patients allergic topenicillin (159). Therefore, conducting randomizedclinical trials to appraise the effectiveness of cipro-floxacin, alone or combined with metronidazole, inperiodontal treatment or to directly compare metro-nidazole+ciprofloxacin and metronidazole+amoxicillinwould be of value to clinicians and patients.

Which subjects would benefit most fromthe antibiotic therapy

The data presented in the previous subitem, as wellas the available literature (Tables 4 and 5; 179, 180,223), suggest that subjects with advanced (Tables 6–8,Figs 4 and 5) or very advanced (Tables 9 and 10,Figs 6 and 7) periodontitis would significantly benefitfrom adjunctive antibiotics, especially metronidazole+ amoxicillin. Furthermore, the few randomized clini-cal trials that assessed the effects of systemic antibiot-ics in the treatment of mild to moderate periodontitis(29, 66, 72, 152) showed clinical and microbiologicalbenefits over those obtained with scaling and rootplaning alone when azithromycin (29, 152) or metro-nidazole (66, 72) were associated with scaling androot planing. Nevertheless, there is an overall percep-tion in periodontology that subjects with mild tomoderate periodontitis would not benefit from sys-temic antibiotics, or if these benefits exist they would

not be important enough to justify the use of a sys-temic drug. In an attempt to assess the effects of sys-temic antibiotics in the treatment of moderateperiodontitis we selected subjects from our databasethat presented, at most, 20 sites with a probing depthof ≥5 mm at baseline. These subjects were dividedaccording to the treatment received as follows:mechanical treatment, either alone (control group) orwith adjunctive metronidazole or metronidazole +amoxicillin (test group). The subjects received clinicaland microbiological monitoring and periodontalmaintenance at 3 months, 6 months and 1 year post-treatment. At baseline, no statistically significant dif-ferences were observed between groups for the clini-cal parameters evaluated (P > 0.05, data not shown).The mean baseline probing depth was 2.9 mm for thetwo groups, and the mean clinical attachment levelwas 3.4 mm and 3.5 mm for the control and testgroups, respectively. The mean number of sites withbaseline probing depth ≥5 mm was 15.5 in the scalingand root planing group and 14.3 in the test group(range: 9–20 sites; Table 11). These baseline clinicaldata confirm the moderate degree of periodontaldestruction in these subjects. At 1 year post-therapy,those who took antibiotics harbored fewer sites withprobing depth ≥5, ≥6 and ≥7 mm, in comparison withthe control group. These differences were statisticallysignificant for the probing depth ≥6 and ≥7 mm cate-gories. Subjects taking systemic metronidazole +amoxicillin also showed greater probing depth reduc-tion and clinical attachment gain in initially interme-diate and deep sites, even though statisticalsignificance was not achieved (Table 12). However, itshould be highlighted that this analysis could beunderpowered as a result of the low number of sub-jects in the scaling and root planing group and there-fore the lack of statistical significance in this caseshould be interpreted with caution. For example, thedifference between groups for probing depth reduc-tion and clinical attachment gain in initially deepsites was about 1 mm, in favor of the antibiotic group(P = 0.067); a difference considered clinically relevantand used for sample size calculation in several ran-domized clinical trials. Presumably a rather relevantand consistent finding relates to the percentage ofsubjects who reached the clinical endpoint for treat-ment at 1 year (Table 13), which was 95% (19/20) inthe antibiotic group compared with 61.5% (eight of13) in the control group. On the other hand, 30.8%(four of 13) of the subjects receiving scaling and rootplaning still had a high risk profile for disease recur-rence at 1 year post-treatment, as opposed to none ofthe 20 subjects receiving adjunctive metronidazole or

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Table 12. Changes in probing depth and clinical attachment between baseline and 3 months, baseline and 6 monthsand baseline and 1 year post-treatment in 33 subjects with moderate periodontitis treated with scaling and root plan-ing alone or with scaling and root planing combined with systemic antibiotics (metronidazole or metronidazole +amoxicillin)

Baselineprobing depth



Scaling and rootplaning +Antb (n = 20)


0–3 months 1.2 � 0.5 1.4 � 0.4 0.106

0–6 months 1.3 � 0.6 1.5 � 0.5 0.099

0–1 year 1.4 � 0.5 1.6 � 0.5 0.069


0–3 months 0.9 � 0.6 1.2 � 0.5 0.140

0–6 months 1.2 � 0.6 1.4 � 0.6 0.385

0–1 year 1.3 � 0.5 1.5 � 0.4 0.458


0–3 months 2.2 � 1.0 3.3 � 1.0 0.000

0–6 months 2.6 � 1.6 3.6 � 1.0 0.059

0–1 year 2.7 � 1.7 3.7 � 0.9 0.069


0–3 months 1.9 � 1.0 2.7 � 1.2 0.011

0–6 months 2.4 � 1.3 3.3 � 1.0 0.099

0–1 year 2.5 � 1.5 3.5 � 1.0 0.067

Values are given as mean � SD. *The significance of differences between groups at each time point was assessed using the Student’s t-test. Antb, antibiotic therapy(five subjects were treated with metronidazole and 15 subjects were treated with metronidazole + amoxicillin).

Table 11. Number of sites with probing depth ≥5, ≥6 and ≥7 mm at baseline and at 3 months, 6 months and 1-yearpost-treatment, as well as changes in number of sites with probing depth ≥5 mm between baseline and 1 year post-treatment in 33 subjects with moderate periodontitis treated with scaling and root planing alone or scaling and rootplaning combined with systemic antibiotics (metronidazole or metronidazole + amoxicillin)

Probing depth Time point Treatment groups P*


Scaling and rootplaning + Antb (n = 20)

≥5 mm Baseline 15.5 � 4.5a 14.3 � 3.6a 0.275

3 months 7.0 � 6.0b 3.8 � 3.0b 0.004

6 months 6.5 � 7.7b 3.2 � 3.9b 0.118

1 year 4.5 � 5.8b 2.4 � 2.2b 0.144

D 0–1 year 8.5 � 6.8 10.5 � 4.2 0.134

≥6 mm Baseline 7.0 � 3.8a 6.0 � 3.4a 0.273

3 months 3.0 � 2.8b 0.9 � 1.2b 0.000

6 months 3.3 � 3.7b 0.6 � 1.0b 0.004

1 year 2.0 � 3.2b 0.4 � 0.6b 0.037

≥7 mm Baseline 3.3 � 2.6a 2.6 � 2.9a 0.344

3 months 1.3 � 1.3b 0.3 � 0.7b 0.000

6 months 1.7 � 1.9b 0.2 � 0.5b 0.002

1 year 1.3 � 1.9b 0.1 � 0.3b 0.007

Values are given as mean � SD. *The significance of differences between groups at each time point was assessed using the Student’s t-test. The significance of differ-ences among time point was determined using repeated-measures analysis of variance and Tukey’s multiple comparison test (different letters indicate significantdifferences between time points). Antb, antibiotic therapy (five subjects were treated with metronidazole and 15 subjects were treated with metronidazole + amoxi-cillin).


165

metronidazole + amoxicillin. This indicates a verygood and steady response to treatment at the subjectlevel when subjects with moderate periodontitis aretreated with these adjunctive antibiotics. The benefi-cial effect of the antibiotics on the composition of thesubgingival microbiota provides the rationale forthese clinical results (Figs 8 and 9). The changes frombaseline to the other follow-up appointments forthe mean counts of the 40 bacterial species evaluatedare presented in Fig. 8. Subjects taking adjunctiveantibiotics in general showed a better change in themicrobial profile in comparison with those treatedwith scaling and root planing. In the test group, frombaseline to 1 year, there was a noticeable reductionin the mean counts of almost all pathogens from thered and orange complexes and a concomitantincrease in the mean levels of the majority of thehost-compatible species from the green, yellow andpurple complexes, as well as the Actinomyces species.In contrast, subjects treated with scaling and rootplaning only showed an overall reduction in the levelsof all species evaluated at 1 year, denoting a lowerimpact on the microbial profile. This observation maybe better appreciated in Fig. 9, which shows the sub-gingival microbial profiles of the two treatmentgroups over the course of the study. Note that at3 months post-treatment the composition of the sub-gingival microbiota of both groups was considerablyimproved in comparison with baseline. Nonetheless,some slight advantages observed for the antibioticgroup in the short term were accentuated over the

course of the study. This was particularly notable forthe mean proportions of red complex species, whichwas reduced from 3.7% at 3 months to 2.3% at 1 yearin the antibiotic-treated group, and increased from7.8% at 3 months to 10.1% at 1 year in the scalingand root planing group. At 1 year, the test group hadstatistically significantly lower proportions of redcomplex species and higher proportions of greencomplex species in comparison with the controlgroup, while the proportion of yellow complex waselevated in the control group. The microbial endpointfor treatment was achieved by 20% and 87.5% of thesubjects in the scaling and root planing and antibioticgroups, respectively. Taken together, these microbio-logical and clinical data indicate that adjunctive met-ronidazole or metronidazole + amoxicillin yield animportant and constant benefit in the treatment ofsubjects with moderate periodontitis.

Smokers are a group of individuals who might par-ticularly benefit from systemic antibiotics becausethey respond less favorably to mechanical periodon-tal treatment (69, 81, 94, 104, 140). Apparently, it ismore difficult to reduce periodontal pathogens and tofoster the growth of host-compatible species in smok-ers than in nonsmokers (28, 57, 129, 130), most prob-ably because of their impaired immune system andinflammatory response (98, 148, 156, 173). Some clini-cal studies have suggested that azithromycin (129),metronidazole (130, 202) or metronidazole + amoxi-cillin (130, 154) lead to additional clinical andmicrobial benefits in the periodontal treatment of

Table 13. Assessment of the risk of disease progression according to Lang & Tonetti (105),* as well as the percentageof subjects with no, one to two, or three or more sites with probing depth ≥6 mm and ≥7 mm at 1-year post-treatment,in 33 subjects with moderate periodontitis treated with scaling and root planing alone or scaling and root planing com-bined with systemic antibiotics (metronidazole + amoxicillin)

Variables Categories Treatment groups P†


Scaling and rootplaning +Antb (n = 20)

Risk for diseaseprogression

Low risk 61.5 95.0 0.014

Moderate risk 7.7 5.0

High risk 30.8 0.0

Probing depth ≥6 mm 0 53.8 70.0 0.465

1–2 15.4 30.0

≥3 30.8 0.0

Probing depth ≥7 mm 0 61.5 90.0 0.083

1–2 30.7 10.0

≥3 7.8 0.0

Values are given as percentage of subjects. *Low risk, at most four sites with probing depth ≥5 mm (the clinical endpoint of treatment); moderate risk, presence offive to eight sites with probing depth ≥5 mm; high risk, presence of nine or more sites with probing depth ≥5 mm. †The significance of differences among groupswas assessed using the chi-square test. Antb, antibiotic therapy (five subjects were treated with metronidazole and 15 subjects were treated with metronida-zole + amoxicillin).

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smokers. We recently treated a group of smokers withscaling and root planing alone, or combined withmetronidazole or metronidazole + amoxicillin, andobserved that the greatest benefits on the clinicalparameters and on the subgingival microbial profilewere achieved with the use of the systemic antibiot-ics, in particular metronidazole + amoxicillin (130).Unexpected was the lack of effect of all three treat-ments in reducing the levels and proportions of theputative pathogens from the orange complex, in par-ticular Fusobacterium species. In fact, some of thesespecies increased in counts at 3 months in those sub-jects treated with scaling and root planing only.Another investigation from our research groupapplied this same study design and microbial analysisin a group of nonsmokers and observed a significantreduction in the proportions of orange complex spe-cies at 3 months post-treatment, especially with theuse of systemic antibiotics (184). To our knowledgeno studies so far have directly compared the effects ofmetronidazole + amoxicillin in the treatment of

smokers and nonsmokers. Therefore, in order toaddress this question we carried out an analysis tocompare the effects of this combination of drugs insmokers and nonsmokers with advanced periodonti-tis (generalized chronic periodontitis) (Tables 14 and15, Figs 10 and 11). The mean baseline probing depthand clinical attachment level were, respectively,3.9 mm and 4.5 mm for nonsmokers and 4.1 mmand 4.7 mm for smokers. No statistically significantdifferences were observed between the two groups atbaseline for any clinical parameter evaluated (datanot shown). At 3 months after treatment withscaling and root planing combined with 400 mg ofmetronidazole + 500 mg of amoxicillin (both threetimes daily for 14 days), the mean number of siteswith probing depth ≥5 mm was statistically signifi-cantly lower (n = 7.9) in nonsmokers in comparisonwith smokers (n = 11.9) (Table 14). When changes inmean probing depth and clinical attachment levelwere analyzed in initially intermediate and deep sites,the data showed significantly greater improvements


A.naeslundii A.oris






C.gracilis C.rectus

C.showae E.nodatum






L.buccalis P.acnes


S.anginosus S.noxia

T.socranskii

5.1

**

*

3.6

***

**

*

*

*****

*

***

**

Counts x105

*

SRPSRP+Antb

Actinomyces

Purple

Yellow

Green

Orange

Red

Others

3 months 6 months 1 year

Fig. 8. Profiles of mean change in the counts (3105) of 40taxa in subgingival biofilm samples taken from subjectswith moderate periodontitis treated with scaling and rootplaning (SRP) alone (n = 13) or combined with systemicantibiotics (SRP+Antb) (n = 20; 400 mg of metronidazoleor 400 mg of metronidazole + 500 mg of amoxicillin; threetimes daily for 14 days) from baseline to 3 months (leftpanel), baseline to 6 months (middle panel) and baselineto 1 year (right panel) post-treatment. Nine subgingivalbiofilm samples were taken from each subject at each time

point and were analyzed separately to determine their con-tent of 40 species of bacteria. The species were ordered andgrouped according to the microbial complexes describedby Socransky et al. (193). Change in counts of each speciesat each site in each of the two clinical groups was deter-mined, averaged within a subject and then across subjectsin each group at each time point. The significance of differ-ences between groups at each time point was determinedusing the Mann–Whitney U-test adjusted for multiple com-parisons [Socransky et al. (199)]; (*P < 0.05; **P < 0.01).


167

in the nonsmokers in comparison with the smokersin both probing depth categories (Table 15). Aftertreatment, 41.6% of the smokers had reached the clin-ical endpoint for treatment compared with 61.5% of

the nonsmokers. The mean proportions of the redcomplex species were reduced in a very similar man-ner in smokers and nonsmokers (Fig. 10). Thesepathogens accounted for about 5% of the 40 species

Fig. 9. Pie charts describing the mean proportions ofmicrobial complexes in subgingival biofilm samplestaken from subjects with moderate periodontitis treatedwith scaling and root planing (SRP), alone (n = 13) orcombined with systemic antibiotics (n = 20; 400 mg ofmetronidazole or 400 mg of metronidazole + 500 mg ofamoxicillin; three times daily for 14 days) (SRP+Antb), atbaseline and at 3 months, 6 months and 1 year post-treatment. Nine subgingival biofilm samples were takenfrom each subject at each time point and were analyzedseparately to determine their content of the 40 species ofbacteria listed in Fig. 8. The percentage of DNA probecounts for each species was determined at each site, thenaveraged within a subject and then across subjects in

each group, at each time point. The mean proportion ofeach species was summed in order to determine the pro-portion of each complex. The colors represent the differ-ent complexes described by Socransky et al. (193). Thegrey color represents species that did not fall into anycomplex, and Actinomyces spp. are represented in blue.The significance of differences within each group overthe course of the study was assessed using Friedman andDunn’s multiple comparison tests (*P < 0.05 betweenbaseline and each time point). The significance ofdifferences between groups at each time point was deter-mined using the Mann–Whitney U-test (different lettersindicate significant differences between pairs of groups,P < 0.05).

Table 14. Number of sites with probing depth ≥5, ≥6 and ≥7 mm at baseline and at 3 months post-treatment, as wellas changes in number of sites with probing depth ≥5 mm between baseline and 3 months post-treatment, in 36 smok-ers and 39 nonsmokers with advanced periodontitis treated with scaling and root planing combined with metronida-zole + amoxicillin

Probing depth Time point Groups P*

Nonsmokers (n = 39) Smokers (n = 36)

≥5 mm Baseline 48.5 � 19.9a 53.5 � 25.3a 0.063

3 months 7.9 � 8.7b 11.9 � 11.1b 0.043

D 0–3 months 40.5 � 16.2 42.4 � 19.4 0.634

≥6 mm Baseline 21.8 � 16.5a 23.4 � 16.8a 0.617

3 months 2.8 � 3.5b 4.4 � 5.9b 0.063

≥7 mm Baseline 10.5 � 11.1a 10.6 � 8.6a 0.460

3 months 1.2 � 2.1b 1.2 � 1.5b 0.139

Values are given as mean � SD. *The significance of differences between groups at each time point was assessed using the Mann–Whitney U-test. The significanceof differences between time points was determined using the Wilcoxon test (different letters indicate significant differences between time points).

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evaluated at 3 months in both groups. On the otherhand, the problem detected in our previous study(130), with regard to the ineffectiveness of treatmentin reducing orange complex species in smokers, wasconfirmed in this analysis. In the nonsmoker group,the orange complex species were reduced from 29.9%of the microbiota evaluated at baseline to 19% at3 months (a mean reduction of 11 percentage points),

whereas no change in this complex was observed inthe smoker group, which showed approximately 31%of orange complex species before and after treatment.The effect of scaling and root planing + metronida-zole + amoxicillin (or lack of effect, in the case ofsmokers) in changing the proportions of orange com-plex, as well as the effect of this treatment in the pro-portions of red complex and Actinomyces species

Table 15. Changes in probing depth and clinical attachment between baseline and 3 months post-treatment in 36smokers and 39 nonsmokers with advanced periodontitis treated with scaling and root planing combined with metro-nidazole + amoxicillin

Baseline probing depth Variables Groups P*

Nonsmokers (n = 39) Smokers (n = 36)

4–6 mm Probing depth reduction (mm) 1.76 � 0.50 1.41 � 0.29 0.001

Clinical attachment gain (mm) 1.31 � 0.47 1.10 � 0.33 0.032

≥7 mm Probing depth reduction (mm) 3.46 � 1.05 2.82 � 0.64 0.000


Values are given as mean � SD. *The significance of differences between groups was assessed using the Mann–Whitney U-test.

Fig. 10. Pie charts describing the mean proportions ofmicrobial complexes in subgingival biofilm samples takenfrom 36 smokers and 39 nonsmokers with advanced peri-odontitis treated with scaling and root planing, combinedwith 400 mg of metronidazole (three times daily for14 days) + 500 mg of amoxicillin (three times daily for14 days), at baseline and at 3 months post-treatment. Ninesubgingival biofilm samples were taken from each subjectat each time point and were analyzed separately to deter-mine their content of the 40 species of bacteria listed inFig. 8. The percentage of DNA probe counts for each specieswas determined at each site, then averaged within a subject

and then across subjects in each group, at each time point.The mean proportion of each species was summed in orderto determine the proportion of each complex. The colorsrepresent the different complexes described by Socranskyet al. (193). The grey color represents species that did notfall into any complex, and Actinomyces spp. are representedin blue. The significance of differences between time pointswas determined using the Wilcoxon test (*P < 0.05). Thesignificance of differences between groups at each timepoint was determined using the Mann–Whitney U-test (dif-ferent letters indicate significant differences between pairsof groups, P < 0.05).


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from baseline to 3 months is presented in Fig. 11.The results confirm that the treatment was equallyeffective in reducing red complex species in bothgroups, and more effective in reducing orange com-plex species and in increasing the proportions of Acti-nomyces in nonsmokers. The microbial endpoint fortreatment was achieved by 18.8% and 43.5% of thesubjects in the smoker and nonsmoker groups,respectively.

In summary, the subgingival microbial profile ofnonsmokers treated with scaling and root planing +metronidazole + amoxicillin showed a better shiftthan that of smokers treated with the same thera-peutic protocol. These microbial benefits elicitedslightly better clinical outcomes for nonsmokers inthe short-term, but in the light of the outcomes oftreatment from 3 months to 1 year described earlierin this article (Fig. 9) it seems reasonable to assumethat these differences might intensify in the longterm. The main difference observed between groupswas the complete lack of effectiveness of scaling androot planing + metronidazole + amoxicillin in reduc-ing the proportions of the orange complex in smok-ers. This is a relevant observation because it hasbeen shown that these species precede the coloniza-tion of the red complex pathogens and therefore

their suppression is considered an important goal ofperiodontal therapy (101, 198). These results indicatethat the generally poorer response of smokers toperiodontal therapy is related to the persistence ofputative pathogens from the orange complex, andnot from the red complex – a common cause of lackof clinical improvement in nonsmokers. Futureinvestigations on potential interactions between sub-stances present in tobacco and species from theorange complex or possible host mechanismsinvolved in this reduced ability of smokers to inhibitthese pathogens may help to determine enhancedperiodontal therapies for these individuals.

What is the ideal dose and duration of thesystemic antibiotics for their use in theperiodontal treatment?

The optimal dose and duration of systemic antibioticsfor the treatment of periodontal diseases have not yetbeen established, often leading to random choices ofantibiotic protocols. These are very important param-eters that need to be defined before prescribing a sys-temic antibiotic because they have a direct impact onthe desirable (e.g. infection control) and undesirable(e.g. side effects and emergence of bacterial resis-tance) effects of these drugs. For example, an antibi-otic taken above the optimal dose may lead to anincrease in the side effects of the drug, whereas anunderdose may not eliminate the target species andmight yield bacterial tolerance to the drug. Normally,the antibiotic protocols (e.g. dose and duration oftherapies) used in dentistry are extrapolations ofthose recommended for medical infections. Thismight result in erroneous prescriptions, especially forthe treatment of periodontal diseases, as a result ofcertain unique features of these conditions that arenot normally observed in medical infections, such asthe microbial protection afforded by the biofilmstructure and the large variation in the concentrationof the drugs in different sites of the oral cavity (174,175, 194).

The lack of clear guidelines and a single protocolfor antibiotic use in periodontal treatment have gen-erated great heterogeneity among the designs of therandomized clinical trials, making the comparison ofthe results of these studies a very difficult task. Theonly exception seems to be the dose of amoxicillin,which has been used in most studies at a dose of 500mg three times daily (2, 40, 42, 55, 59, 85, 95, 119, 120,122, 123, 130, 137–139, 141, 146, 184, 212, 215, 221).On the other hand, the ideal dose of metronidazolefor the treatment of periodontal infections has been

0.0

–5.0

–10.0

–15.0

–20.0

5.0

10.0

15.013.1

–11.0

–18.7 –19.1

5.4

0.8

*

Nonsmokers Smokers

Mea

n p

rop

ort

ion

(%

)Actinomyces

Orange complex

Red complex

*

Fig. 11. Bar charts of the mean changes in the proportionsof Actinomyces species (Actinomyces gerencseriae, Actino-myces israelii, Actinomyces naeslundii and Actinomycesoris), orange and red complexes in subgingival biofilmsamples taken from 36 smokers and 39 nonsmokers withadvanced periodontitis treated with scaling and root plan-ing combined with 400 mg of metronidazole (three timesdaily for 14 days) + 500 mg of amoxicillin (three timesdaily for 14 days), between baseline and 3 months post-treatment. The significance of differences between treat-ment groups was determined using the Mann–Whitney U-test (*P < 0.05).

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more controversial as it has been administered threetimes daily in a variety of different doses, such as 200/250 mg (10, 16, 33, 40, 50, 66, 72, 85, 95, 112, 116, 118,122, 123, 141, 142, 146, 166, 170, 212) and 400/500 mg(2, 14, 15, 18, 19, 42, 55, 59, 130, 137–139, 183, 184,215, 221). Another important issue is the duration ofthe treatment with metronidazole, amoxicillin or thecombination of both, which is also not completelydefined and normally varies from 7 (2, 16, 18, 19, 55,59, 123, 141, 142, 146, 154, 166, 170, 214, 215, 221), to8 (33, 183), 10 (10, 14, 15, 85, 95, 137, 212) or 14 (40,42, 50, 66, 72, 130, 138, 139, 168, 184) days. When bothdose and duration of these systemic antibiotics are

taken into consideration, the variation of the studyprotocols is even higher. Thus, with the data currentlyavailable it is difficult to determine, for example, ifthe benefits achieved with 250 mg of metronidazoleadministered for 14 days are comparable with thoseobtained with a higher dose (e.g. 400 mg) adminis-tered for fewer days (e.g. 7 days). The answers tothese questions are crucial because they are directlyassociated with treatment effectiveness and patientcomfort. Let us consider a hypothetical situation inwhich the two protocols outlined above would pro-vide the same clinical benefit with similar side effects.In this case, the protocol using a higher dose

Table 16. Number of sites with probing depth ≥5, ≥6 and ≥7 mm at baseline and at 3 months post-treatment in 60subjects with advanced periodontitis treated with scaling and root planing alone, or scaling and root planing combinedwith 250 mg or 400 mg of metronidazole + 500 mg of amoxicillin for 7 or 14 days

Probingdepth

Timepoint

Treatment groups P*

7 days 14 days


Amoxicillin +metronidazole250 mg (n = 12)




≥5 mm Baseline 33.1 � 21.6a 35.7 � 22.5a 36.7 � 22.1a 32.1 � 24.2a 31.2 � 18.4a 0.943

3 months 17.1 � 14.0A,b 11.2 � 12.3b 11.4 � 8.2b 9.8 � 8.2B,b 6.3 � 9.9B,b 0.001


3 months 10.2 � 10.8A,b 5.0 � 7.0B,b 5.0 � 4.4B,b 4.7 � 3.9B,b 2.2 � 4.8B,b 0.006


3 months 4.9 � 6.2A,b 2.5 � 3.7B,b 2.4 � 2.2B,b 1.9 � 1.8B,b 0.9 � 3.1B,b 0.007

Values are given as mean � SD. *The significance of differences among groups at each time point was assessed using the Kruskal–Wallis and Dunn’s multiple com-parison tests (different capital letters indicate significant differences between pairs of groups). The significance of differences between time points was determinedusing the Wilcoxon test (different lower-case letters indicate significant differences between time points).

Table 17. Changes in probing depth and clinical attachment between baseline and 3 months post-treatment in 60subjects with advanced periodontitis treated with scaling and root planing alone, or scaling and root planing combinedwith 250 mg or 400 mg of metronidazole + 500 mg of amoxicillin for 7 or 14 days



7 days 14 days







1.1 � 0.5A 1.5 � 0.4B 1.6 � 0.4B 1.7 � 0.3B 1.8 � 0.5B 0.010


0.6 � 0.6 1.0 � 0.7 1.0 � 0.7 1.0 � 0.4 1.1 � 0.5 0.335


1.9 � 1.0A 3.3 � 1.0B 3.3 � 0.8B 3.5 � 0.9B 3.6 � 1.4B 0.006


1.3 � 1.0A 2.2 � 1.4 2.1 � 0.8 2.5 � 1.3B 2.5 � 1.2B 0.011

Values are given as mean � SD. *The significance of differences among groups at each time point was assessed using the Kruskal–Wallis and Dunn’s multiple com-parison tests (different letters indicate significant differences between pairs of groups).


171

(400 mg), for a shorter period of time (7 days), wouldbe the most recommended because it could increasepatient adherence to treatment and minimize theproblems of bacterial resistance to drugs. The sys-temic administration of antibiotics for long periods oftime is the main cause of the lack of patient compli-ance (52).

In an attempt to improve the protocol for theclinical use of metronidazole + amoxicillin, weconducted the following double-blind, placebo-con-trolled clinical trial. A group of nonsmoker subjectswith advanced periodontitis (generalized chronicperiodontitis) were randomly assigned to receivescaling and root planing, either alone (controlgroup) or combined with 250 mg or 400 mg of met-ronidazole three times daily + 500 mg of amoxicillinthree times daily, for either 7 or 14 days (total offour test groups). Subjects were clinically monitored

at baseline and at 3 months post-therapy. No statis-tically significant differences were observed amongthe five groups at baseline (data not shown). Themean probing depth and clinical attachment level ofthe five groups varied from 3.7 mm to 3.9 mm andfrom 4.1 mm to 4.7 mm, respectively. Subjectsreceiving systemic antibiotics at any dosage or dura-tion exhibited generally better clinical results incomparison with those treated with scaling and rootplaning only (Tables 16 and 17). However, at3 months post-therapy, only the two test groupsreceiving systemic antibiotics for 14 days showed astatistically significant lower mean number of resid-ual sites with probing depth ≥5 mm (n = 9.8 for250 mg of metronidazole + 500 mg of amoxicillin;and n = 6.3 for 400 mg of metronidazole + 500 mgof amoxicillin) in comparison with the control group(n = 17.1) (Table 16). In addition, subjects in these

0.0 12.3 24.6 36.9 49.1

**

SRP


A.naeslundii A.oris






C.gracilis C.rectus

C.showae E.nodatum




S.constellatus T.forsythia

P.gingivalis T.denticola


L.buccalis P.acnes


S.anginosus S.noxia

T.socranskii

0.0 12.3 24.6 36.9 49.1

*

*

*

**

*

***

*

MTZ 250 mg0.0 12.3 24.6 36.9 49.1

*

*

****

**

MTZ 400 mg0.0 12.3 24.6 36.9 49.1

*

**

****

***

***

**

MTZ 250 mg0.0 12.3 24.6 36.9 49.1

*

*

****

**

*

MTZ 400 mg

7 days 14 days

****

**

**

Baseline3 months

Counts x105

Actinomyces

Purple

Yellow

Green

Orange

Red

Others

Fig. 12. Profiles of mean counts (3105) of 40 taxa in subgin-gival biofilm samples taken from 60 subjects with advancedperiodontitis treated with scaling and root planing (SRP),alone or combined with 250 mg or 400 mg of metronida-zole (MTZ) + 500 mg of amoxicillin for 7 or 14 days at base-line and at 3 months post-treatment. Nine subgingivalbiofilm samples were taken from each subject at each timepoint and were analyzed separately to determine their con-

tent of 40 species of bacteria. The species were ordered andgrouped according to the microbial complexes described bySocransky et al. (193). The mean values for each specieswere averaged within a subject and then across subjects ineach group at each time point. The significance of differ-ences between time points was determined using the Wilco-xon test adjusted for multiple comparisons [Socransky et al.(199)] (*P < 0.05; **P < 0.01).

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two groups also presented the greatest gain in clini-cal attachment at initially deep sites in comparisonwith those treated with scaling and root planingonly (P < 0.05) (Table 17). In accordance with theclinical changes, the most striking beneficial changesin the subgingival microbial composition wereobserved in the two test groups receiving thesystemic antibiotics for 14 days (Figs 12 and 13).Subjects in all antibiotic groups showed a statisti-cally significant reduction in the individual levels ofthe three red complex pathogens (T. forsythia, P.gingivalis and T. denticola) but the two groups withthe longer period of antibiotic administration(14 days) also had a reduction in five putativepathogens from the orange complex, against one ortwo species in the other three groups (Fig. 12). Inaddition, at 3 months post-therapy, these two testgroups, but not those two taking the antibiotics for7 days, showed statistically significantly lowerresidual mean proportions of red complex (5.7% for250 mg of metronidazol; 5.1% for 400 mg of

metronidazole) in comparison with the controlgroup (15.5%) (Fig. 13). No statistically significantdifferences were observed for the clinical and micro-biological parameters evaluated between the twogroups taking 250 or 400 mg of metronidazole for7 days or between those taking 250 or 400 mg ofmetronidazole for 14 days. However, within the 14-days antibiotic regimen, there was a tendencytoward better results for the higher-dose subgroup(400 mg), mainly for the number of residual siteswith probing depth ≥5 mm post-therapy. No statisti-cally significant differences were observed amongthe four antibiotic groups for the individual adverseeffects reported.

In summary, these short-term preliminary datasuggest that the duration of the metronidazole +amoxicillin intake interferes with treatment success.The adjunctive use of these antibiotics for 14 days,irrespective of the metronidazole dosage, offersshort-term clinical and microbiological benefits overscaling and root planing alone, in the treatment ofadvanced periodontitis. The added benefits of the 7-days antibiotic regimen were less evident.

In which phase of the mechanicaltreatment should the antibiotic beprescribed?

Two different questions related to the ideal time forsystemic antibiotic use in periodontal treatmentremain unanswered: (i) should the antibiotic(s) beadministered during the active phase of therapy or onre-evaluation (i.e. 3 or 6 months after active treat-ment); and (ii) should the antibiotic(s) be adminis-tered on the first or last day of the scaling and rootplaning procedure?

Let us focus on the first question: ‘Should the anti-biotic (s) be administered during the active phase oftherapy or on re-evaluation?’. Two previous investiga-tions– one retrospective study (96) and a randomizedclinical trial (55) – have addressed this question, andthe results of both studies suggested greater clinicalbenefits when metronidazole + amoxicillin wereprescribed at the initial phase of therapy than in there-evaluation period. This statement is in line withthe notion, already strengthened in this article, that arapid and striking reduction in the subgingivalmicrobiota would be necessary in order to obtain themost beneficial recolonization possible of therecently scaled pockets. Milder perturbations mightnot be enough to change the highly stable climaxcommunity of the mature biofilm (194, 198). Asrecolonization is partially achieved at 3 months

0.0

4.0

8.0

12.0

16.0Red complex

Mea

n p

rop

ort

ion

(%

)

SRP MTZ 250 mg MTZ 400 mg MTZ 250 mg MTZ 400 mg

14 days7 days

A

B

B

(T. forsythia, P. gingivalis and T. denticola)

Fig. 13. Bar charts of the mean proportions of the threered complex bacterial species (Tannerella forsythia, Por-phyromonas gingivalis and Treponema denticola) in sub-gingival biofilm samples taken from 60 subjects withadvanced periodontitis treated with scaling and root plan-ing (SRP) alone or combined with 250 mg or 400 mg ofmetronidazole (MTZ) + 500 mg of amoxicillin for 7 or14 days, at 3 months post-treatment. Nine subgingivalbiofilm samples were taken from each subject at each timepoint and were analyzed separately to determine theircontent of the three red complex species. The percentageof DNA probe counts for each species was determined ateach site, then averaged within a subject and then acrosssubjects in each group. The mean proportion of eachspecies was summed in order to determine the proportionof the red complex. The significance of differencesamong groups was determined using Kruskal–Wallis andDunn’s multiple comparison tests (different letters indi-cate significant differences between pairs of groups,P < 0.05).


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post-scaling and root planing there is a chance thatthe antibiotic given at this stage would work almostas a maintenance scaling. On the other hand, moreaggressive treatments applied at once, such as theassociation of scaling and root planing and antibioticsduring the initial therapy, would have greater poten-tial to create an entirely new and stable climax com-munity, similar to that observed in health.

Two aspects associated with the presence of a moreintense inflammatory process before the implemen-tation of mechanical treatment also provide addi-tional arguments for the antibiotic(s) prescription atthe initial phase of therapy: (i) the higher concentra-tion of antibiotic delivered to the subgingival area asa result of the increased levels of gingival crevicularfluid; and (ii) higher permeability of capillaries, whichmay contribute to enhanced antibiotic uptake (96).Hence, when the clinician makes the decision toappraise the results of the initial treatment in order toevaluate the need for prescribing a systemic

antibiotic, he/she might naively incur some errors,such as producing a series of mild and not totallyeffective disturbances to biofilm and preventinghigher concentrations of the drugs from reaching thesubgingival sites.

Another important point to consider when makingthe decision to postpone the administration of antibi-otics to the maintenance phase is related to somelimitations of our evaluation of ‘treatment success’.Periodontists have always been challenged by the dif-ficult task of having to appraise the resolution of aninfection using clinical tools. Fortunately, goodparameters to assess clinical success have been estab-lished by well-conducted and robust clinical studies,such as the number of residual sites with probingdepth ≥5 mm (105, 132, 133), a parameter used in thepresent article to determine the clinical endpoint fortreatment. However, no matter how good the clinicalparameter used to determine treatment success maybe, the clinical results alone may not provide all the

Fig. 14. Pie charts describing the mean proportions ofmicrobial complexes in subgingival biofilm samples takenfrom subjects who showed a very good clinical response at3 months post-treatment (i.e. presented at most four siteswith probing depth ≥ 5 mm, the clinical endpoint for treat-ment). Subjects were treated with scaling and root planing(SRP) alone (n = 10) or combined with systemic antibiotics(SRP+Antibiotics)(n=10); 400 mg of metronidazole or 400mg of metronidazole + 500 mg of amoxicillin; three timesdaily for 14 days. Nine subgingival biofilm samples weretaken from each subject at baseline, and at 3 months and1 year post-treatment, and were analyzed separately todetermine their content of the 40 species of bacteria listedin Fig. 12. The percentage of DNA probe counts for eachspecies was determined at each site, then averaged within

a subject and then across subjects in each group at eachtime point. The mean proportion of each species wassummed in order to determine the proportion of eachcomplex. The colors represent the different complexesdescribed by Socransky et al. (193). The grey color repre-sents species that did not fall into any complex, andActinomyces spp. are represented in blue. The significanceof differences within each group over the course of thestudy was assessed using Friedman and Dunn’s multiplecomparison tests (*P < 0.05 between baseline and3 months and baseline and 1 year). The significance of dif-ferences between groups at each time point was deter-mined using the Mann–Whitney U-test (different lettersindicate significant differences between pairs of groups,P < 0.05).

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information necessary to compare the effectivenessof two therapies because similar clinical profiles mayharbor distinct microbiota – which, in turn, mightinfluence the maintenance of the clinical results lon-gitudinally. An example of this situation is presentedin Fig. 14, which presents the microbiological profileof two groups of subjects who showed a very goodclinical response [at most four sites with probingdepth ≥5 mm (i.e. achieved the clinical endpoint fortreatment)] at 3 months after being treated with scal-ing and root planing only (n = 10) or combined witheither metronidazole or metronidazole + amoxicillin(n = 10). Slight differences in the composition of thesubgingival microbiota could be observed betweenthe two groups in the short term. Subjects whoreceived antibiotics had statistically significant lowermean proportions of red complex species (1.7%) anda slightly higher proportion of Actinomyces species(34%) compared with those treated with scaling androot planing only (7.9% and 28.7%, respectively) at3 months. Although these differences were notsufficient to impact the clinical parameters in theshort term, they were accentuated over time, an effect

similar to that observed in subjects with moderatedisease (Fig. 9). At 1 year, subjects taking antibioticsharbored 2% of red complex species and the meanproportions of Actinomyces species reached 38.6%compared with 11.5% and 20.8% observed in the scal-ing and root planing group, respectively. This worsen-ing in the microbial profile at 1 year impacted on theclinical status, and 30% (three of 10) of the subjectsfrom the scaling and root planing group had anincrease in the number of sites with probing depth≥5 mm, losing their status of low-risk profile for fur-ther disease progression. On the other hand, all sub-jects who took antibiotics at the beginning of thetreatment maintained the low risk profile up to 1 yearafter treatment. These findings reinforce the risk ofwaiting for 3 or 6 months to take the decision ofprescribing antibiotics. However, a more precise rec-ommendation of the best time to give the systemicantibiotics will only be possible by conducting ran-domized clinical trials specifically designed to testthese two protocols directly.

The second question to be addressed concerningthe best time to administer the systemic antibiotics

Table 18. Changes in probing depth and clinical attachment between baseline and 3 months post-treatment in 29subjects with advanced periodontitis treated with scaling and root planing combined with metronidazole + amoxicillinstarting with the first session or immediately after the last session of scaling and root planing

Baseline probingdepth

Variables Treatment groups P*

First session (n = 14) Last session (n = 15)

4–6 mm Probing depth reduction (mm) 1.6 � 0.4 1.7 � 0.4 0.258


≥7 mm Probing depth reduction (mm) 3.5 � 1.0 3.6 � 0.7 0.378


Values are given as mean � SD. *The significance of differences between groups was assessed using the Mann–Whitney U-test.

Table 19. Number of sites with probing depth ≥5, ≥6 and ≥7 mm at baseline and at 3 months post-treatment in 29subjects with advanced periodontitis treated with scaling and root planing combined with metronidazole + amoxicillinstarting at the first session or immediately after the last session of scaling and root planing

Probingdepth


First session (n = 14) Last session (n = 15)

≥5 mm Baseline 48.6 � 18.5a 53.0 � 16.7a 0.783

3 months 6.0 � 5.2b 5.2 � 4.4b 0.456

≥6 mm Baseline 26.6 � 16.1a 28.8 � 15.3a 0.515

3 months 2.71 � 3.4b 1.9 � 3.6b 0.019

≥7 mm Baseline 14.2 � 11.5a 16.1 � 10.6a 0.732

3 months 1.0 � 2.0b 1.0 � 2.2b 0.149

Values are given as mean number of sites � SD. The significance of differences between time points was determined using Wilcoxon test (different letters indicatesignificant differences between time points). *The significance of differences between groups at each time point was assessed using the Mann–Whitney U-test.


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is: ‘should the antibiotic (s) be administered at thefirst or at the last session of the scaling and rootplaning procedure?’ No randomized clinical trial todate has directly addressed this question, and intheory there are biologically plausible explanationsto justify both protocols. One argument in favor ofadministration of the systemic antibiotic at the endof the mechanical treatment is to reduce the pro-tective effect of the biofilm before the drug is deliv-ered to the site of infection. On the other hand,delivering the antibiotic on the first day of scalingand root planing could have the same benefits asthe administration of the antibiotics at the initialtreatment phase, which are: a more rapid andstriking reduction of the subgingival microbiota,leading to a more beneficial recolonization of the

treated sites (208) and the two positive aspectsmentioned above, associated with the intenseinflammatory process present at the beginning oftreatment (i.e. higher antibiotic concentration as aresult of increased levels of gingival crevicular fluidand better antibiotic uptake owing to increasedcapillary permeability). In order to address thisquestion directly we conducted a double-blind, pla-cebo-controlled clinical trial with 29 subjects pre-senting advanced periodontitis (generalizedaggressive periodontitis). The subjects were ran-domly assigned to receive scaling and root planingcombined with metronidazole (400 mg, three timesdaily for 14 days) + amoxicillin (500 mg, threetimes daily for 14 days) starting with the first ses-sion or immediately after the last session of scaling

0.0 4.2 8.5 12.7 17.0

**

*

*

***

*

* ***

0.0 4.2 8.5 12.7 17.0

***

*

**

***

**

First session

Baseline3 months


A.naeslundii A.oris




A.actinomycetemcomitansC.gingivalis C.ochracea


C.gracilis C.rectus

C.showae E.nodatum




S.constellatus T.forsythia

P.gingivalis T.denticola


L.buccalis P.acnes


S.anginosus S.noxia

T.socranskii

DNA probe counts (%)

Actinomyces

Purple

Yellow

Green

Orange

Others

Red

Immediately after last session

Fig. 15. Profiles of the mean proportions (%) of 40 taxa insubgingival biofilm samples taken from subjects withadvanced periodontitis treated with scaling and root plan-ing combined with 400 mg of metronidazole (three timesdaily for 14 days) + 500 mg of amoxicillin (three timesdaily for 14 days), starting with the first session (n = 14) orimmediately after the last session of scaling and root plan-ing (n = 15); at baseline and at 3 months post-treatment.Nine subgingival biofilm samples were taken from eachsubject at each time point and were analyzed separately to

determine their content of 40 species of bacteria. The spe-cies were ordered and grouped according to the microbialcomplexes described by Socransky et al. (193). The per-centage of DNA probe counts for each species were deter-mined at each site, averaged within a subject and thenacross subjects in each group at each time point. The sig-nificance of differences between time points was deter-mined using the Wilcoxon test adjusted for multiplecomparisons [Socransky et al. (199)] (*P < 0.05;**P < 0.01).

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and root planing. Subjects received clinical andmicrobiological monitoring at baseline and at3 months post-scaling and root planing. At base-line, no statistically significant differences wereobserved between groups for the clinical parame-ters evaluated (P > 0.05, data not shown). Themean probing depth and clinical attachment levelwere, respectively, 3.8 mm and 2.7 mm in the con-trol group and 3.9 mm and 2.7 mm in the testgroup. Both antibiotic groups showed similar clini-cal benefits, including a reduction in the meanprobing depth and a gain in clinical attachment ininitially intermediate and deep sites (Table 18). Inaddition, both groups exhibited fewer residual siteswith probing depth ≥5 mm at 3 months post-treat-ment (antibiotic/first scaling and root planing ses-sion, n = 6, antibiotic/last scaling and root planingsession, n = 5.2, P > 0.05) (Table 19). The microbio-logical effects of the two antibiotic protocols werealso quite similar (Fig. 15). In summary, no impor-tant short-term differences were observed in theclinical and microbiological parameters whenadjunctive metronidazole + amoxicillin treatmentstarted together or immediately after scaling androot planing. However, randomized clinical trialswith larger sample sizes and with longer follow-upperiods would be very important to draw moredefinitive conclusions about the use of these twoprotocols.

Concluding thoughts

The concepts and the data discussed in this articlesupport the notion that treatment of periodontitis isan ecological intervention and that clinical improve-ment is associated with the suppression of periodon-tal pathogens and recolonization of the biofilm byhost-compatible species. This is not an easy goal toachieve, especially when dealing with a highly orga-nized climax biofilm community, such as the maturesubgingival biofilm associated with periodontitis. Thenotion that pathogens are not restricted to deep peri-odontal pockets, but might be present at high levelsand proportions in supragingival biofilm, in ‘healthy’sites and in all oral surfaces of individuals with peri-odontitis complicates, even further, achievement ofthe ecological change necessary to re-establishperiodontal health. In the light of this knowledge, itseems quite unlikely that a mechanical treatment,such as scaling and root planing, targeting only micro-organisms present on the tooth surface, primarily inmoderate and deep pockets, would be the best treat-

ment to achieve this goal. Indeed, current evidencesuggests that the beneficial changes in the subgingivalmicrobial composition achieved with scaling and rootplaning can be considerably improved by the adjunc-tive use of metronidazole or metronidazole + amoxi-cillin, and these microbiological benefits areaccompanied by important and sustained clinicalimprovements. Considering the endpoint for treat-ment used in the analyses presented in this article,that is the presence of at most four sites with aprobing depth ≥5 mm, the number of subjects receiv-ing scaling and root planing alone who could beconsidered as ‘successfully treated’ was always lowerthan the number of those receiving adjunctive metro-nidazole or metronidazole + amoxicillin. One of thefindings with the greatest impact was that even sub-jects with moderate periodontitis, or those who showan excellent clinical short-term response to treatment,would be at a lower risk for future disease progressionif they were treated with one of these antibiotic proto-cols (Figs 9 and 14). An additional benefit of metroni-dazole + amoxicillin was observed in certain analyses/studies (130, 184, Table 8 and Fig. 5). Besides theoverall trend of better clinical and microbiologicaleffects with the combination of both antibiotics, thistherapy yielded statistically significant greater probingdepth reduction and clinical attachment gain in ini-tially intermediate sites and an increase in the propor-tions of the beneficial Actinomyces species, incomparison with metronidazole alone.

Metronidazole and amoxicillin seem to produce aseries of ecological benefits. The first is the effect ofthese antibiotics in reducing the numbers of majorperiodontal pathogens, such as that of metronidazoleon strict anaerobes and of metronidazole + amoxicil-lin on A. actinomycetemcomitans (117, 211). Recent datasuggest that the striking inhibition of keystone patho-gens would help to reverse the dysbiotic changes inthe subgingival microbiota improving the composi-tion of the entire biofilm community (73, 74). Inaddition, the antibiotics could potentially controlperiodontal pathogens present in the other oral sur-faces, tissues, fluids, epithelial cells and connectivetissue; and the broad-spectrum activity of amoxicillinmight potentiate the effect of scaling and root plan-ing, leading to a more rapid and profound reductionof the bacterial load in the subgingival space. Anotherpossible role of the antibiotics given at the initialphase of periodontal therapy is to suppress the over-growth of species, such as some proteolytic patho-gens, that could benefit from tissue damage duringscaling and root planing. This would diminish inflam-mation in the local tissues during healing, which, in


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turn, would hinder an increase in the proportions ofthese same pathogens – a common event in microbialecology, where colonizing species affect the habitatand the habitat affects the colonizing organisms(194). The combination of all the effects describedabove would allow a recolonization of the recentlyscaled pockets by the host-compatible initial coloniz-ers, preventing the species of the red complex (andpossibly other pathogens) from recolonizing in highnumbers and proportions (38, 130, 138, 184) (Figs 4–9).This new climax biofilm community, which is morecompatible with health, is rather stable and difficultto disturb, and would enable the long-term stabilityof the periodontium (42, 50) (Tables 6–13).

Apparently, the notion that periodontitis can be,most of the time, successfully treated by scaling androot planing only should at least be questioned.Despite that, scaling and root planing continues to beconsidered as the gold standard treatment for peri-odontal diseases. Why is this? One of the reasons isthe concept established in the 1990s that few, if any,species would be affected by an antibiotic reachingthe subgingival space as a result of the biofilm-con-ferred antibiotic tolerance. This clearly is not the case,as shown by all the data and studies described in thisarticle. Another possible reason for the delay in incor-porating the antibiotics in the clinical practice relatesto the risks associated with the administration ofpharmacologically active agents, such as the develop-ment of side effects. In addition, there is the generalfear that the administration of a systemic antibioticmay lead to the emergence of ‘new’ antibiotic-resis-tant species, either by selecting for a mutation in theorganism’s genome or by activating the expression ofpreviously existing antibiotic-resistance genes. In theworst-case scenario, these genes could be transferredwithin or between species, giving rise to a new bacte-rial population resistant to the agent in question.There seem to be no major side effects associatedwith the intake of metronidazole and amoxicillin(18, 42, 59, 130, 138, 179, 180, 184) and indirect datasuggest that increased proportions of antibiotic-resistant species in the subgingival biofilm appear tooccur largely as a result of selection of organisms thatwere naturally resistant to the antibiotic before anti-biotic administration (39, 66, 169). Assessing theemergence of ‘new’ antibiotic-resistant species ismore challenging. To conduct investigations specifi-cally designed to seek species that were previouslysensitive to the tested antibiotics that became resis-tant to the drug after its administration is very diffi-cult, and unfortunately these data are not available inthe literature. Therefore, the recommendation of

antibiotics to treat periodontal infection should fol-low the same principle used for the treatment of anyother infection, that is: the risks need to be clearly off-set by benefits to the patient – benefits that could notbe otherwise achieved or which would be achievedwith much greater difficulty or risk by other means.In this regard, both the reduced need for periodontalsurgery and the lower levels of pathogens associatedwith the administration of systemic antibiotics, espe-cially metronidazole+amoxicillin, need to be consid-ered. In other words, the risks associated withperforming additional surgical procedures and withthe presence of higher levels of pathogenic bacteria inthe subgingival environment (for the patient`s localand systemic health) should be included in the risk–benefit evaluation.

Ultimately, the lack of clear guidelines and a singleprotocol for the use of systemic antibiotics asadjuncts to periodontal treatment, such as definitionof the ideal dose and duration, and the moment ofantibiotic administration, has also discouraged theuse of these agents in the periodontal practice. Someof the data presented in the present article help to(partially) answer some of these questions. Prelimin-ary data suggest that starting the antibiotic intake atthe first or at the last scaling and root planing sessiondoes not significantly impact the results of treatment(Tables 18 and 19 and Fig. 15), but apparently theintake of metronidazole+amoxicillin for 14 dayswould lead to greater clinical and microbiologicalimprovements than their administration for 7 days,with similar safety and tolerability (Tables 16 and 17,Figs 12 and 13). These two final statements need tobe confirmed by longitudinal data, longer than3 months of follow-up. Moreover, possibly the antibi-otics should be administered during the initial phaseof treatment, and the decision about whether or notto prescribe these drugs should not be postponed tothe re-evaluation phase. This statement is based inone randomized clinical trial (55), one retrospectivestudy (96) and on the biological concepts presentedin this article, but also needs to be confirmed by con-trolled randomized clinical trials.

In summary, it is expected that all the recentknowledge on the ecology of the periodontal infec-tions and the additional and long-lasting beneficialeffects of metronidazole and metronidazole+amoxi-cillin in the treatment of periodontitis demonstratedby well-conducted randomized clinical trials with 1–2 years of follow-up will finally lead to a change inthe periodontal treatment protocols, including theuse of these antibiotics during the active phase ofperiodontal therapy.

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Acknowledgment

This work was supported, in part, by research grants5 R03 TW006269-02 DE-from the National Institute ofDental and Craniofacial Research (NIDCR, USA);2007/56413-0, 2007/55291-9, 2009/17677-8, 2010/10384-2 and 2011/23034-2 from S~ao Paulo ResearchFoundation (FAPESP, Brazil); and 311765/2006-8,308308/2009-3, 308550/2009-9 and 306314/2010-0from The National Council for Scientific and Techno-logical Development (CNPq, Brazil).

References

1. Addy M, Langeroudi M. Comparison of the immediateeffects on the sub-gingival microflora of acrylic strips con-taining 40% chlorhexidine, metronidazole or tetracycline.J Clin Periodontol 1984: 11: 379–386.

2. Aimetti M, Romano F, Guzzi N, Carnevale G. Full-mouthdisinfection and systemic antimicrobial therapy ingeneralized aggressive periodontitis: a randomized,placebo-controlled trial. J Clin Periodontol 2012: 39: 284–294.

3. Ali RW, Lie T, Skaug N. Early effects of periodontal therapyon the detection frequency of four putative periodontalpathogens in adults. J Periodontol 1992: 63: 540–547.

4. Ardila CM, Fern�andez N, Guzm�an IC. Antimicrobial sus-ceptibility of moxifloxacin against gram-negative entericrods from colombian patients with chronic periodontitis.J Periodontol 2010: 81: 292–299.

5. Ardila CM, Granada MI, Guzm�an IC. Antibiotic resistanceof subgingival species in chronic periodontitis patients.J Periodontal Res 2010: 45: 557–563.

6. Ardila CM, L�opez MA, Guzm�an IC. High resistance againstclindamycin, metronidazole and amoxicillin in Porphyro-monas gingivalis and Aggregatibacter actinomycetemcomi-tans isolates of periodontal disease. Med Oral Patol OralCir Bucal 2010: 15: 947–951.

7. Azmak N, Atilla G, Luoto H, Sorsa T. The effect of subgingi-val controlled-release delivery of chlorhexidine chip onclinical parameters and matrix metalloproteinase-8 levelsin gingival crevicular fluid. J Periodontol 2002: 73: 608–615.

8. Badersten A, Nilv�eus R, Egelberg J. Effect of nonsurgicalperiodontal therapy. I. Moderately advanced periodontitis.J Clin Periodontol 1981: 8: 57–72.

9. Balmes P, Clerc G, Dupont B, Labram C, Pariente R, PoirierR. Comparative study of azithromycin and amoxicillin/cla-vulanic acid in the treatment of lower respiratorytract infections. Eur J Clin Microbiol Infect Dis 1991: 10:437–439.

10. Baltacioglu E, Aslan M, Sarac� €O, Saybak A, Yuva P. Analysisof clinical results of systemic antimicrobials combinedwith nonsurgical periodontal treatment for generalizedaggressive periodontitis: a pilot study. J Can Dent Assoc2011: 77: b97.

11. Bonito AJ, Lux L, Lohr KN. Impact of local adjuncts to scal-ing and root planing in periodontal disease therapy: a sys-tematic review. J Periodontol 2005: 76: 1227–1236.

12. Bonta Y, Zambon JJ, Genco RJ, Neiders ME. Rapid identifi-cation of periodontal pathogens in subgingival plaque:comparison of indirect immunofluorescence microscopywith bacterial culture for detection of Actinobacillus ac-tinomycetemcomitans. J Dent Res 1985: 64: 793–798.

13. Botero JE, Contreras A, Lafaurie G, Jaramillo A, BetancourtM, Arce RM. Occurrence of periodontopathic and superin-fecting bacteria in chronic and aggressive periodontitissubjects in a Colombian population. J Periodontol 2007:78: 696–704.

14. Carvalho LH, D’Avila GB, Le~ao A, Gonc�alves C, HaffajeeAD, Socransky SS, Feres M. Scaling and root planing,systemic metronidazole and professional plaque removalin the treatment of chronic periodontitis in a Brazilianpopulation II–microbiological results. J Clin Periodontol2005: 32: 406–411.

15. Carvalho LH, D’Avila GB, Le~ao A, Haffajee AD, SocranskySS, Feres M. Scaling and root planing, systemic metronida-zole and professional plaque removal in the treatment ofchronic periodontitis in a Brazilian population. I. Clinicalresults.. J Clin Periodontol 2004: 31: 1070–1076.

16. Casarin RC, Peloso Ribeiro ED, Sallum EA, Nociti FH Jr,Gonc�alves RB, Casati MZ. The combination of amoxicillinand metronidazole improves clinical and microbiologicresults of one-stage, full-mouth, ultrasonic debridement inaggressive periodontitis treatment. J Periodontol 2012: 83:988–998.

17. Choi BK, Park SH, Yoo YJ, Choi SH, Chai JK, Cho KS, KimCK. Detection of major putative periodontopathogens inKorean advanced adult periodontitis patients using anucleic acid-based approach. J Periodontol 2000: 71: 1387–1394.

18. Cionca N, Giannopoulou C, Ugolotti G, Mombelli A.Amoxicillin and metronidazole as an adjunct to full-mouthscaling and root planing of chronic periodontitis. J Period-ontol 2009: 80: 364–371.

19. Cionca N, Giannopoulou C, Ugolotti G, Mombelli A.Microbiologic testing and outcomes of full-mouth scalingand root planing with or without amoxicillin/metronida-zole in chronic periodontitis. J Periodontol 2010: 8: 15–23.

20. Cobb CM. Clinical significance of nonsurgical periodontaltherapy: an evidence-based perspective of scaling and rootplaning. J Clin Periodontol 2002: 29(Suppl. 2): 6–16.

21. Colombo AP, Boches SK, Cotton SL, Goodson JM, Kent R,Haffajee AD, Socransky SS, Hasturk H, Van Dyke TE,Dewhirst F, Paster BJ. Comparisons of subgingivalmicrobial profiles of refractory periodontitis, severe peri-odontitis, and periodontal health using the human oralmicrobe identification microarray. J Periodontol 2009: 80:1421–1432.

22. Colombo AP, Teles RP, Torres MC, Rosal�em W, MendesMC, Souto RM, Uzeda M. Effects of non-surgical mechani-cal therapy on the subgingival microbiota of Brazilianswith untreated chronic periodontitis: 9-month results.J Periodontol 2005: 76: 778–784.

23. Colombo AP, Teles RP, Torres MC, Souto R, Rosal�em WJ,Mendes MC, Uzeda M. Subgingival microbiota of Braziliansubjects with untreated chronic periodontitis. J Periodon-tol 2002: 73: 360–369.

24. Costerton JW, Stewart PS, Greenberg EP. Bacterial bio-films: a common cause of persistent infections. Science1999: 21: 1318–1322.


179

25. Cuesta AI, Jewtuchowicz V, Brusca MI, Nastri ML, RosaAC. Prevalence of Staphylococcus spp and Candida spp inthe oral cavity and periodontal pockets of periodontal dis-ease patients. Acta Odontol Latinoam 2010: 23: 20–26.

26. Cugini MA, Haffajee AD, Smith C, Kent RL Jr, SocranskySS. The effect of scaling and root planing on the clinicaland microbiological parameters of periodontal diseases:12-month results. J Clin Periodontol 2000: 27: 30–36.

27. Dahl�en G, Wikstr€om M. Occurrence of enteric rods, staph-ylococci and Candida in subgingival samples. Oral Micro-biol Immunol 1995: 10: 42–46.

28. Darby IB, Hodge PJ, Riggio MP, Kinane DF. Clinical andmicrobiological effect of scaling and root planing in smo-ker and non-smoker chronic and aggressive periodontitispatients. J Clin Periodontol 2005: 32: 200–206.

29. Dastoor SF, Travan S, Neiva RF, Rayburn LA, GiannobileWV, Wang HL. Effect of adjunctive systemic azithromycinwith periodontal surgery in the treatment of chronic peri-odontitis in smokers: a pilot study. J Periodontol 2007: 78:1887–1896.

30. De Soete M, Mongardini C, Peuwels M, Haffajee A, Socran-sky S, van Steenberghe D, Quirynen M. One-stage full--mouth disinfection. Long-term microbiological resultsanalyzed by checkerboard DNA–DNA hybridization. J Peri-odontol 2001: 72: 374–382.

31. Doungudomdacha S, Rawlinson A, Walsh TF, Douglas CW.Effect of nonsurgical periodontal treatment on clinicalparameters and the numbers of Porphyromonas gingivalis,Prevotella intermedia and Actinobacillus actinomycetem-comitans at adult periodontitis sites. J Clin Periodontol2001: 28: 437–445.

32. Dzink JL, Socransky SS, Ebersole JL, Frey DE. ELISA andconventional techniques for identification of black-pig-mented Bacteroides isolated from periodontal pockets. JPerio Res 1983: 18: 369–374.

33. Ehmke B, Moter A, Beikler T, Milian E, Flemmig TF.Adjunctive antimicrobial therapy of periodontitis: long--term effects on disease progression and oral colonization.J Periodontol 2005: 76: 749–759.

34. Emingil G, Han B, Ozdemir G, Tervahartiala T, Vural C,Atilla G, Baylas H, Sorsa T. Effect of azithromycin, as anadjunct to nonsurgical periodontal treatment, on microbi-ological parameters and gingival crevicular fluid biomar-kers in generalized aggressive periodontitis. J Perio Res2012: 47: 729–739.

35. Faveri M, Feres M, Shibli JA, Hayacibara RF, HayacibaraMM, de Figueiredo LC. Microbiota of the dorsum of thetongue after plaque accumulation: an experimental studyin humans. J Periodontol 2006: 77: 1539–1546.

36. Faveri M, Figueiredo LC, Duarte PM, Mestnik MJ, MayerMP, Feres M. Microbiological profile of untreated subjectswith localized aggressive periodontitis. J Clin Periodontol2009: 36: 739–749.

37. Faveri M, Mayer MP, Feres M, de Figueiredo LC, DewhirstFE, Paster BJ. Microbiological diversity of generalizedaggressive periodontitis by 16S rRNA clonal analysis. OralMicrobiol Immunol 2008: 23: 112–118.

38. Feres M. Antibiotics in the treatment of periodontal dis-eases: microbiological basis and clinical applications. AnnR Australas Coll Dent Surg 2008: 19: 37–44.

39. Feres M, Haffajee AD, Allard K, Som S, Goodson JM,Socransky SS. Antibiotic resistance of subgingival species

during and after antibiotic therapy. J Clin Periodontol2002: 29: 724–735.

40. Feres M, Haffajee AD, Allard K, Som S, Socransky SS.Change in subgingival microbial profiles in adult peri-odontitis subjects receiving either systemically-adminis-tered amoxicillin or metronidazole. J Clin Periodontol2001: 28: 597–609.

41. Feres M, Haffajee AD, Goncalves C, Allard KA, Som S,Smith C, Goodson JM, Socransky SS. Systemic doxycyclineadministration in the treatment of periodontal infections(II). Effect on antibiotic resistance of subgingival species.J Clin Periodontol 1999: 26: 784–792.

42. Feres M, Soares GMS, Mendes JAV, Silva MP, Faveri M,Teles R, Socransky SS, Figueiredo LC. Metronidazole aloneor with amoxicillin as adjuncts to nonsurgical treatment ofchronic periodontitis: a 1-year double-blinded, pla-cebo-controlled, randomized clinical trial. J Clin Periodon-tol 2012: 39: 1149–1158.

43. Fujise O, Hamachi T, Inoue K, Miura M, Maeda K. Micro-biological markers for prediction and assessment of treat-ment outcome following non-surgical periodontaltherapy. J Periodontol 2002: 73: 1253–1259.

44. Gajardo M, Silva N, Gomez L, Leon R, Parra B, ContrerasA, Gamonal J. Prevalence of periodontopathic bacteria inaggressive periodontitis patients in a Chilean population.J Periodontol 2005: 76: 289–294.

45. Gladue RP, Bright GM, Isaacson RE, Newborg MF. In vitroand in vivo uptake of azithromycin by phagocytic cells:possible mechanism of delivery and release at sites ofinfection. Antimicrob Agents Chemother 1989: 33: 277–282.

46. Gladue RP, Snider ME. Intracellular accumulation of azi-thromycin by cultured human fibroblasts. AntimicrobAgents Chemother 1990: 34: 1056–1060.

47. Gomi K, Yashima A, Nagano T, Kanazashi M, Maeda N,Arai T. Effects of full-mouth scaling and root planing inconjunction with systemically administered azithromycin.J Periodontol 2007: 78: 422–429.

48. Gonc�alves LFH, Fermiano D, Feres M, Figueiredo LC, TelesFRP, Mayer MPA, Faveri M. Levels of Selenomonas speciesin genereralized aggressive periodontitis. J Periodontal Res2012: 47: 711–718.

49. Goodson JM. Antimicrobial strategies for treatment ofperiodontal diseases. Periodontol 2000 1994: 5: 142–168.

50. Goodson JM, Haffajee AD, Socransky SS, Kent R, Teles R,Hasturk H, Bogren A, Van Dyke T, Wennstrom J, Lindhe J.Control of periodontal infections: a randomized controlledtrial I. The primary outcome attachment gain and pocketdepth reduction at treated sites. J Clin Periodontol 2012:39: 525–536.

51. Goodson JM, Hogan PE, Dunham SL. Clinical responsesfollowing periodontal treatment by local drug delivery.J Periodontol 1985: 56: 81–87.

52. Greenberg RN. Overview of patient compliance with medi-cation dosing: a literature review. Clin Ther 1984: 6: 592–599.

53. Greenstein G. Local drug delivery in the treatment of peri-odontal diseases: assessing the clinical significance of theresults. J Periodontol 2006: 77: 565–578.

54. Griffen AL, Beall CJ, Campbell JH, Firestone ND, KumarPS, Yang ZK, Podar M, Leys EJ. Distinct and complex bac-terial profiles in human periodontitis and health revealedby 16S pyrosequencing. ISME J 2012: 6: 1176–1185.

Feres et al.

180

55. Griffiths GS, Ayob R, Guerrero A, Nibali L, Suvan J, MolesDR, Tonetti MS. Amoxicillin and metronidazole as anadjunctive treatment in generalized aggressive periodonti-tis at initial therapy or re-treatment: a randomized con-trolled clinical trial. J Clin Periodontol 2011: 38: 43–49.

56. Grisi DC, Salvador SL, Figueiredo LC, Souza SL, NovaesAB, Grisi MF. Effect of a controlled-release chlorhexidinechip on clinical and microbiological parameters of peri-odontal syndrome. J Clin Periodontol 2002: 29: 875–881.

57. Grossi SG, Goodson JM, Gunsolley JC, Otomo-Corgel J,Bland PS, Doherty F, Comiskey J. Mechanical therapy withadjunctive minocycline microspheres reduces red-com-plex bacteria in smokers. J Periodontol 2007: 78: 1741–1750.

58. Guerrero A, Echeverr�ıa JJ, Tonetti MS. Incomplete adher-ence to an adjunctive systemic antibiotic regimendecreases clinical outcomes in generalized aggressive peri-odontitis patients: a pilot retrospective study. J ClinPeriodontol 2007: 34: 897–902.

59. Guerrero A, Griffiths GS, Nibali L, Suvan J, Moles DR, Lau-rell L, Tonetti MS. Adjunctive benefits of systemic amoxi-cillin and metronidazole in non-surgical treatment ofgeneralized aggressive periodontitis: a randomized pla-cebo controlled clinical trial. J Clin Periodontol 2005: 32:1096–1107.

60. Haas AN, de Castro GD, Moreno T, Susin C, Albandar JM,Oppermann RV, R€osing CK. Azithromycin as an adjunctivetreatment of aggressive periodontitis: 12-months random-ized clinical trial. J Clin Periodontol 2008: 35: 696–704.

61. Haas AN, Silva-Boghossian CM, Colombo AP, Susin C, Al-bandar JM, Oppermann RV, R€osing CK. Adjunctive azi-thromycin in the treatment of aggressive periodontitis:microbiological findings of a 12-month randomizedclinical trial. J Dent 2012: 40: 556–563.

62. Haffajee AD, Bogren A, Hasturk H, Feres M, Lopez NJ, Soc-ransky SS. Subgingival microbiota of chronic periodontitissubjects from different geographic locations. J Clin Period-ontol 2004: 31: 996–1002.

63. Haffajee AD, Cugini MA, Dibart S, Smith C, Kent RL Jr, Soc-ransky SS. The effect of SRP on the clinical and microbio-logical parameters of periodontal diseases. J ClinPeriodontol 1997: 24: 324–334.

64. Haffajee AD, Dibart S, Kent RLJ, Socransky SS. Clinical andmicrobiological changes associated with the use of 4adjunctive systemically administered agents in the treat-ment of periodontal infections. J Clin Periodontol 1995: 22:618–627.

65. Haffajee AD, Japlit M, Bogren A, Kent RL Jr, Goodson JM,Socransky SS. Differences in the subgingival microbiota ofSwedish and USA subjects who were periodontally healthyor exhibited minimal periodontal disease. J Clin Periodon-tol 2005: 32: 33–39.

66. Haffajee AD, Patel M, Socransky SS. Microbiologicalchanges associated with four different periodontal thera-pies for the treatment of chronic periodontitis. Oral Micro-biol Immunol 2008: 23: 148–157.

67. Haffajee AD, Socransky SS, Gunsolley JC. Systemicanti-infective periodontal therapy. A systematic review.Ann Periodontol 2003: 8: 115–181.

68. Haffajee AD, Socransky SS, Patel MR, Song X. Microbialcomplexes in supragingival plaque. Oral Microbiol Immu-nol 2008: 23: 196–205.

69. Haffajee AD, Socransky SS. Relationship of cigarette smok-ing to attachment level profiles. J Clin Periodontol 2001:28: 283–295.

70. Haffajee AD, Teles RP, Socransky SS. Association of Eubac-terium nodatum and Treponema denticola with humanperiodontitis lesions. Oral Microbiol Immunol 2006: 21:269–282.

71. Haffajee AD, Teles RP, Socransky SS. The effect of peri-odontal therapy on the composition of the subgingivalmicrobiota. Periodontol 2000 2006: 42: 219–258.

72. Haffajee AD, Torresyap G, Socransky SS. Clinical changesfollowing four different periodontal therapies for thetreatment of chronic periodontitis: 1-year results. J ClinPeriodontol 2007: 34: 243–253.

73. Hajishengallis G, Darveau RP, Curtis MA. The key-stone-pathogen hypothesis. Nat Rev Microbiol 2012: 10:717–725.

74. Hajishengallis G, Lamont RJ. Beyond the red complex andinto more complexity: the polymicrobial synergy and dys-biosis (PSD) model of periodontal disease etiology. MolOral Microbiol 2012: 27: 409–419.

75. Hallmon WW, Rees TD. Local anti-infective therapy:mechanical and physical approaches. A systematic review.Ann Periodontol 2003: 8: 99–114.

76. Hamlet SM, Cullinan MP, Westerman B, Lindeman M, BirdPS, Palmer J, Seymour GJ. Distribution of Actinobacillusactinomycetemcomitans, Porphyromonas gingivalis andPrevotella intermedia in an Australian population. J ClinPeriodontol 2001: 28: 1163–1171.

77. Han B, Emingil G, Ozdemir G, Tervahartiala T, Vural C,Atilla G, Baylas H, Sorsa T. Azithromycin as an adjunctivetreatment of generalized severe chronic periodontitis: clin-ical, microbiological and biochemical parameters. J Peri-odontol 2012: 83: 1480–1491.

78. Hanes PJ, Purvis JP. Local anti-infective therapy: pharma-cological agents. A systematic review. Ann Periodontol2003: 8: 79–98.

79. Haraszthy VI, Hariharan G, Tinoco EM, Cortelli JR, LallyET, Davis E, Zambon JJ. Evidence for the role of highly leu-kotoxic Actinobacillus actinomycetemcomitans in the path-ogenesis of localized juvenile and other forms ofearly-onset periodontitis. J Periodontol 2000: 71: 912–922.

80. Haubek D, Ennibi OK, Abdellaoui L, Benzarti N, Poulsen S.Attachment loss in Moroccan early onset periodontitispatients and infection with the JP2-type of Actinobacillusactinomycetemcomitans. J Clin Periodontol 2002: 29: 657–660.

81. Heasman L, Stacey F, Preshaw PM, McCracken GI, Hep-burn S, Heasman PA. The effect of smoking on periodontaltreatment response: a review of clinical evidence. J ClinPeriodontol 2006: 33: 241–253.

82. Heasman PA, Heasman L, Stacey F, McCracken GI. Localdelivery of chlorhexidine gluconate (PerioChip) in peri-odontal maintenance patients. J Clin Periodontol 2001: 28:90–95.

83. Heitz-Mayfield LJ, Trombelli L, Heitz F, Needleman I,Moles D. A systematic review of the effect of surgicaldebridement vs non-surgical debridement for the treat-ment of chronic periodontitis. J Clin Periodontol 2002: 29:92–102.

84. Heller D, Silva-Boghossian CM, do Souto RM, ColomboAP. Subgingival microbial profiles of generalized


181

aggressive and chronic periodontal diseases. Arch OralBiol 2012: 57: 973–980.

85. Heller D, Varela VM, Silva-Senem MX, Torres MCB,Feres-Filho EJ, Colombo APV. Impact of systemic antimicro-bials combined to anti-infective mechanical debridementon the microbiota of generalized aggressive periodontitis: a6-month RCT. J Clin Periodontol 2011: 38: 355–364.

86. Henry DC, Riffer E, Sokol WN, Chaudry NI, Swanson RN.Randomized double-blind study comparing 3- and 6-dayregimens of azithromycin with a 10-day amoxicillin-clavul-anate regimen for treatment of acute bacterial sinusitis.Antimicrob Agents Chemother 2003: 47: 2770–2774.

87. Herrera D, Sanz M, Jepsen S, Needleman I, Roldan S. Asystematic review on the effect of systemic antimicrobialsas an adjunct to scaling and root planing in periodontitispatients. J Clin Periodontol 2002: 29(Suppl. 3): 136–159.

88. Hinrichs JE, Wolff LF, Pihlstrom BL, Schaffer EM, LiljemarkWF, Bandt CL. Effects of scaling and root planing on sub-gingival microbial proportions standardized in terms oftheir naturally occurring distribution. J Periodontol 1985:56: 187–194.

89. Hoepelman IM, Schneider MME. Azithromycin: the first ofthe tissue-selective azalides. Int J Antimicrob Agents 1995:5: 145–167.

90. Hung HC, Douglass CW. Meta-analysis of the effect of scal-ing and root planing, surgical treatment and antibiotictherapies on periodontal probing depth and attachmentloss. J Clin Periodontol 2002: 29: 975–986.

91. Hussein I, Ranka M, Gilbert A, Davey K. Locally deliveredantimicrobials in the management of periodontitis: a criti-cal review of the evidence for their use in practice. DentUpdate 2007: 34: 494–496, 499–502, 505–506.

92. Ioannou I, Dimitriadis N, Papadimitriou K, Sakellari D,Vouros I, Konstantinidis A. Hand instrumentation versusultrasonic debridement in the treatment of chronic peri-odontitis: a randomized clinical and microbiological trial.J Clin Periodontol 2009: 36: 132–141.

93. Iwase M, Slots J, Berthold P, Taichman NS. Leukocidalactivity of staphylococci isolated from human periodontallesions. Oral Microbiol Immunol 1990: 5: 233–236.

94. Johnson G, Guthmiller JM. The impact of cigarette smok-ing on the periodontal disease and treatment. Periodontol2000 2007: 14: 178–194.

95. Kaner D, Bernimoulin JP, Hopfenm€uller W, Kleber BM,Friedmann A. Controlled-delivery chlorhexidine chip ver-sus amoxicillin/metronidazole as adjunctive antimicrobialtherapy for generalized aggressive periodontitis: a ran-domized controlled clinical trial. J Clin Periodontol 2007:34: 880–891.

96. Kaner D, Christan C, Dietrich T, Bernimoulin JP, KleberBM, Friedmann A. Timing affects the clinical outcome ofadjunctive systemic antibiotic therapy for generalizedaggressive periodontitis. J Periodontol 2007: 78: 1201–1208.

97. Kim YC, Ko Y, Hong SD, Kim KY, Lee YH, Chae C, Choi Y.Presence of Porphyromonas gingivalis and plasma celldominance in gingival tissues with periodontitis. Oral Dis2010: 16: 375–381.

98. Kinane DF, Chestnutt IG. Smoking and periodontaldisease. Crit Rev Oral Biol Med 2000: 11: 356–365.

99. Kinane DF, Radvar M. A six-month comparison of threeperiodontal local antimicrobial therapies in persistentperiodontal pockets. J Periodontol 1999: 70: 1–7.

100. Kn€ofler GU, Purschwitz RE, Eick S, Pfister W, Roedel M,Jentsch HF. Microbiologic findings 1 year after partial-and full-mouth scaling in the treatment of moderatechronic periodontitis. Quintessence Int 2011: 42: 107–117.

101. Kolenbrander PE, Palmer RJ Jr, Rickard AH, Jakubovics NS,Chalmers NI, Diaz PI. Bacterial interactions and succes-sions during plaque development. Periodontol 2000 2006:42: 47–79.

102. Kumar PS, Griffen AL, Barton JA, Paster BJ, MoeschbergerML, Leys EJ. New bacterial species associated with chronicperiodontitis. J Dent Res 2003: 82: 338–344.

103. Kumar PS, Griffen AL, Moeschberger ML, Leys EJ. Identifi-cation of candidate periodontal pathogens and beneficialspecies by quantitative 16S clonal analysis. J Clin Microbiol2005: 43: 3944–3955.

104. Labriola A, Needleman I, Moles DR. Systematic review ofthe effect of smoking on nonsurgical periodontal therapy.Periodontol 2000 2005: 37: 124–137.

105. Lang NP, Tonetti MS. Periodontal risk assessment (PRA)for patients in supportive periodontal therapy (SPT). OralHealth Prev Dent 2003: 1: 7–16.

106. Lee HJ, Kang IK, Chung CP, Choi SM. The subgingivalmicroflora and gingival crevicular fluid cytokines inrefractory periodontitis. J Clin Periodontol 1995: 22:885–890.

107. Lepp PW, Brinig MM, Ouverney CC, Palm K, Armitage GC,Relman DA. Methanogenic Archaea and human periodon-tal disease. Proc Natl Acad Sci USA 2004: 20: 6176–6181.

108. Levy RM, Giannobile WV, Feres M, Haffajee AD, Smith C,Socransky SS. The effect of apically repositioned flap sur-gery on clinical parameters and the composition of thesubgingival microbiota: 12-month data. Int J PeriodontRest Dent 2002: 22: 209–219.

109. Li CL, Liu DL, Jiang YT, Zhou YB, Zhang MZ, Jiang W, LiuB, Liang JP. Prevalence and molecular diversity of Archaeain subgingival pockets of periodontitis patients. OralMicrobiol Immunol 2009: 24: 343–346.

110. Lindhe J, Liljenberg B. Treatment of localized juvenileperiodontitis. Results after 5 years. J Clin Periodontol 1984:11: 399–410.

111. Lindhe J, Liljenberg B, Adielson B, Borjesson I. The effectof metronidazole therapy on human periodontal disease.J Periodontal Res 1982: 17: 534–536.

112. Loesche WJ, Giordano JR, Soehren S, Kaciroti N. The non-surgical treatment of patients with periodontal disease:results after 6.4 years. Gen Dent Curr Infect Dis 2005: 53:298–306.

113. Loesche WJ, Grossman NS. Periodontal disease as a spe-cific, albeit chronic, infection: diagnosis and treatment.Clin Microbiol Rev 2001: 14: 727–752.

114. Loesche WJ, Grossman N, Giordano J. Metronidazole inperiodontitis (IV). The effect of patient compliance ontreatment parameters. J Clin Periodontol 1993: 20: 96–104.

115. Loesche WJ, Schmidt E, Smith BA, Caffessee R, Stoll J. Met-ronidazole therapy for periodontitis. J Periodontal Res1987: 22: 224–226.

116. Loesche WJ, Schmidt E, Smith BA, Morrison EC, CaffesseR, Hujoel PP. Effects of metronidazole on periodontaltreatment needs. J Periodontol 1991: 62: 247–257.

117. Loesche WJ, Syed SA, Laughon BE, Stoll J. The bacteriologyof acute necrotizing ulcerative gingivitis. J Periodontol1982: 53: 223–230.

Feres et al.

182

118. Loesche WJ, Syed SA, Morrison EC, Kerry GA, Higgins T,Stoll J. Metronidazole in periodontitis. I. Clinical and bac-teriological results after 15 to 30 weeks. J Periodontol 1984:55: 325–335.

119. L�opez NJ, Gamonal JA. Effects of metronidazole plusamoxicillin in progressive untreated adult periodontitis:results of a single 1-week course after 2 and 4 months.J Periodontol 1998: 69: 1291–1298.

120. L�opez NJ, Gamonal JA, Martinez B. Repeated metronida-zole and amoxicillin treatment of periodontitis. A fol-low-up study. J Periodontol 2000: 71: 79–89.

121. L�opez NJ, Mellado JC, Leighton GX. Occurrence of Actino-bacillus actinomycetemcomitans, Porphyromonas gingiva-lis and Prevotella intermedia in juvenile periodontitis.J Clin Periodontol 1996: 23: 101–105.

122. L�opez NJ, Quintero A, Casanova PA, Ibieta CI, Baelum V,L�opez R. Effects of periodontal therapy on systemic mark-ers of inflammation in patients with metabolic syndrome:a controlled clinical trial. J Periodontol 2012: 83: 267–278.

123. L�opez NJ, Socransky SS, Da Silva I, Japlit MR, Haffajee AD.Effects of metronidazole plus amoxicillin as the only ther-apy on the microbiological and clinical parameters ofuntreated chronic periodontitis. J Clin Periodontol 2006:33: 648–660.

124. L�opez NJ, Socransky SS, Da Silva I, Japlit MR, Haffajee AD.Subgingival microbiota of chilean patients with chronicperiodontitis. J Periodontol 2004: 75: 717–725.

125. Mager DL, Ximenez-Fyvie LA, Haffajee AD, Socransky SS.Distribution of selected bacterial species on intraoral sur-faces. J Clin Periodontol 2003: 30: 644–654.

126. Mandell RL, Ebersole JL, Socransky SS. Clinicalimmunologic and microbiologic features of active diseasesites in juvenile periodontitis. J Clin Periodontol 1987: 14:534–540.

127. Mandell RL, Socransky SS. Microbiological and clinicaleffects of surgery plus doxycycline on juvenile periodonti-tis. J Periodontol 1988: 59: 373–379.

128. Marsh PD, Devine DA. How is the development of dentalbiofilms influenced by the host? J Clin Periodontol 2011:38(Suppl. 11): 28–35.

129. Mascarenhas P, Gapski R, Al-Shammari K, Hill R, SoehrenS, Fenno JC, Giannobile WV, Wang HL. Clinical responseof azithromycin as an adjunct to non-surgical periodontaltherapy in smokers. J Periodontol 2005: 76: 426–436.

130. Matarazzo F, Figueiredo LC, Cruz SE, Faveri M, Feres M.Clinical and microbiological benefits of systemic metroni-dazole and amoxicillin in the treatment of smokers withchronic periodontitis: a randomized placebo-controlledstudy. J Clin Periodontol 2008: 35: 885–896.

131. Matarazzo F, Ribeiro AC, Feres M, Faveri M, Mayer MP.Diversity and quantitative analysis of Archaea in aggres-sive periodontitis and periodontally healthy subjects. JClin Periodontol 2011: 38: 621–627.

132. Matuliene G, Pjetursson BE, Salvi GE, Schmidlin K,Br€agger U, Zwahlen M, Lang NP. Influence of residualpockets on progression of periodontitis and tooth loss:results after 11 years of maintenance. J Clin Periodontol2008: 35: 685–695.

133. Matuliene G, Studer R, Lang NP, Schmidlin K, PjeturssonBE, Salvi GE, Br€agger U, Zwahlen M. Significance of peri-odontal risk assessment in the recurrence of periodontitisand tooth loss. J Clin Periodontol 2010: 37: 191–199.

134. Mayanagi G, Sato T, Shimauchi H, Takahashi N. Detectionfrequency of periodontitis-associated bacteria by polymer-ase chain reaction in subgingival and supragingival plaqueof periodontitis and healthy subjects. Oral MicrobiolImmunol 2004: 19: 379–385.

135. McColl E, Patel K, Dahlen G, Tonetti M, Graziani F, SuvanJ, Laurell L. Supportive periodontal therapy using mechan-ical instrumentation or 2% minocycline gel: a 12 monthrandomized, controlled, single masked pilot study. J ClinPeriodontol 2006: 33: 141–150.

136. Mdala I, Haffajee AD, Socransky SS, de Blasio BF, Thore-sen M, Olsen I, Goodson JM. Multilevel analysis of clinicalparameters in chronic periodontitis after root planing/scaling, surgery, and systemic and local antibiotics: 2-yearresults. J Oral Microbiol 2012. Doi: 10.3402/jom.v4i0.17535.

137. Mendonc�a AC, Santos VR, Ribeiro FV, Lima JA, MirandaTS, Feres M, Duarte PM. Surgical and non-surgical therapywith systemic antimicrobials for residual pockets in type 2diabetics with chronic periodontitis: a pilot study. J ClinPeriodontol 2012: 39: 368–376.

138. Mestnik MJ, Feres M, Figueiredo LC, Duarte PM, Lira EA,Faveri M. Short-term benefits of the adjunctive use of met-ronidazole plus amoxicillin in the microbial profile and inthe clinical parameters of subjects with generalizedaggressive periodontitis. J Clin Periodontol 2010: 37: 353–365.

139. Mestnik MJ, Feres M, Figueiredo LC, Soares G, Teles RP,Fermiano D, Duarte PM, Faveri M. The effects of adjunc-tive metronidazole plus amoxicillin in the treatment ofgeneralized aggressive periodontitis: a 1-year dou-ble-blinded, placebo-controlled, randomized clinical Trial.J Clin Periodontol 2012: 39: 955–961.

140. Meulman T, Casarin RC, Peruzzo DC, Giorgetti AP, Barba-gallo A, Casati MZ, Sallum EA, Gonc�alves RB, Nociti FH Jr.Impact of supragingival therapy on subgingival microbialprofile in smokers versus non-smokers with severe chronicperiodontitis. J Oral Microbiol 2012. Doi: 10.3402/jom.v4i0.8640.

141. Moeintaghavi A, Talebi-ardakani MR, Haerian-ardakani A,Zandi H, Taghipour S, Fallahzadeh H, Pakzad A, FahamiN. Adjunctive effects of systemic amoxicillin and metroni-dazole with scaling and root planing: a randomized, pla-cebo controlled clinical trial. J Contemp Dent Pract 2007: 8:51–59.

142. Mombelli A, Brochut P, Plagnat D, Casagni F, Giannopou-lou C. Enamel matrix proteins and systemic antibiotics asadjuncts to non-surgical periodontal treatment: clinicaleffects. J Clin Periodontol 2005: 32: 225–230.

143. Mombelli A, Lehmann B, Tonetti M, Lang NP. Clinicalresponse to local delivery of tetracycline in relation tooverall and local periodontal conditions. J Clin Periodontol1997: 24: 470–477.

144. Mombelli A, Schmid B, Rutar A, Lang NP. Persistence pat-terns of Porphyromonas gingivalis, Prevotella intermedia/nigrescens, and Actinobacillus actinomycetemcomitansafter mechanical therapy of periodontal disease. J Period-ontol 2000: 71: 14–21.

145. Moore WE, Holdeman LV, Cato EP, Smibert RM,Burmeister JA, Palcanis KG, Ranney RR. Comparative bac-teriology of juvenile periodontitis. Infect Immun 1985: 48:507–519.


183

146. Moreira RM, Feres-Filho EJ. Comparison betweenfull-mouth scaling and root planing and quadrant-wisebasic therapy of aggressive periodontitis: 6-month clinicalresults. J Periodontol 2007: 78: 1683–1688.

147. Morillo JM, Lau L, Sanz M, Herrera D, Martin C, Silva A.Quantitative real-time polymerase chain reaction basedon single copy gene sequence for detection of periodontalpathogens. J Clin Periodontol 2004: 31: 1054–1060.

148. Mouzakiti E, Pepelassi E, Fanourakis G, Markopoulou C,Tseleni-Balafouta S, Vrotsos I. Expression of MMPs andTIMP-1 in smoker and nonsmoker chronic periodontitispatients before and after periodontal treatment. J Peri-odontal Res 2012: 47: 532–542.

149. Newman MG, Socransky SS. Predominant cultivablemicrobiota in periodontosis. J Periodontal Res 1977: 12:120–128.

150. Novak MJ, Polson AM, Adair SM. Tetracycline therapy inpatients with early juvenile periodontitis. J Periodontol1988: 59: 366–372.

151. Novak MJ, Stamatelakys C, Adair SM. Resolution of earlylesions of juvenile periodontitis with tetracycline therapyalone: long-term observations of 4 cases. J Periodontol1991: 62: 628–633.

152. Oteo A, Herrera D, Figuero E, O’Connor A, Gonz�alez I,Sanz M. Azithromycin as an adjunct to scaling and rootplaning in the treatment of Porphyromonas gingiva-lis-associated periodontitis: a pilot study. J Clin Periodon-tol 2010: 37: 1005–1015.

153. Ouverney CC, Armitage GC, Relman DA. Single-Cell enu-meration of an uncultivated TM7 subgroup in the humansubgingival crevice. Appl Eviron Microbiol 2003: 69: 6294–6298.

154. Pahkla ER, Koppel T, Naaber P, Saag M, Loivukene K. Theefficacy of non-surgical and systemic antibiotic treatmenton smoking and non-smoking periodontitis patients.Stomatologija 2006: 8: 116–121.

155. Palmer RM, Matthews JP, Wilson RF. Non-surgical peri-odontal treatment with and without adjunctive metroni-dazole in smokers and non-smokers. J Clin Periodontol1999: 26: 158–163.

156. Palmer RM, Wilson RF, Hasan AS, Scott DA. Mechanismsof action of environmental factors – tobacco smoking.J Clin Periodontol 2005: 32: 180–195.

157. Pavia M, Nobile CG, Angelillo IF. Meta-analysis of local tet-racycline in treating chronic periodontitis. J Periodontol2003: 74: 916–932.

158. Pavia M, Nobile CG, Bianco A, Angelillo IF. Meta-analysisof local metronidazole in the treatment of chronic peri-odontitis. J Periodontol 2004: 75: 830–838.

159. Pavicic MJ, van Winkelhoff AJ, de Graaff J. In vitro suscep-tibilities of Actinobacillus actinomycetemcomitans to anumber of antimicrobial combinations. Antimicrob AgentsChemother 1992: 36: 2634–2638.

160. Pavicic MJ, van Winkelhoff AJ, Douqu�e NH, Steures RW,de Graaff J. Microbiological and clinical effects of metroni-dazole and amoxicillin in Actinobacillus actinomycetem-comitans-associated periodontitis. A 2-year evaluation.J Clin Periodontol 1994: 21: 107–112.

161. Pedrazzoli V, Kilian M, Karring T, Kirkegaard E. Effect ofsurgical and non-surgical periodontal treatment on peri-odontal status and subgingival microbiota. J Clin Period-ontol 1991: 18: 598–604.

162. Pihlstrom BL, McHugh RB, Oliphant TH, Ortiz-Campos C.Comparison of surgical and nonsurgical treatment of peri-odontal disease. A review of current studies and additionalresults after 61/2 years. J Clin Periodontol 1983: 10:524–541.

163. Ramberg P, Rosling B, Serino G, Hellstr€om MK, SocranskySS, Lindhe J. The long-term effect of systemic tetracyclineused as an adjunct to non-surgical treatment of advancedperiodontitis. J Clin Periodontol 2001: 28: 446–452.

164. Ramfjord SP, Caffesse RG, Morrison EC, Hill RW, Kerry GJ,Appleberry EA, Nissle RR, Stults DL. Four modalities ofperiodontal treatment compared over five years. J Peri-odontal Res 1987: 22: 222–223.

165. Rams TE, Slots J. Local delivery of antimicrobial agents inthe periodontal pocket. Periodontol 2000 1996: 10: 139–159.

166. Ribeiro EP, Bittencourt S, Zanin IC, Bovi Ambrosano GM,Sallum EA, Nociti FH, Gonc�alves RB, Casati MZ.Full-mouth ultrasonic debridement associated with amox-icillin and metronidazole in the treatment of severechronic periodontitis. J Periodontol 2009: 80: 1254–1264.

167. Riviere GR, Smith KS, Tzagaroulaki E, Kay SL, Zhu X, DeR-ouen TA, Adams DF. Periodontal status and detection fre-quency of bacteria at sites of periodontal health andgingivitis. J Periodontol 1996: 67: 109–115.

168. Rodrigues DC, Taba MJ, Novaes AB, Souza SL, Grisi MF.Effect of non-surgical periodontal therapy on glycemiccontrol in patients with type 2 diabetes mellitus. J Period-ontol 2003: 74: 1361–1377.

169. Rodrigues RMJ, Gonc�alves C, Souto R, Feres-Filho EJ, Uze-da M, Colombo APV. Antibiotic resistance profile of thesubgingival microbiota following systemic or local tetracy-cline therapy. J Clin Periodontol 2004: 31: 420–427.

170. Rooney J, Wade WG, Sprague SV, Newcombe RG, Addy M.Adjunctive effects to non-surgical periodontal therapy ofsystemic metronidazole and amoxycillin alone and com-bined. A placebo controlled study. J Clin Periodontol 2002:29: 342–350.

171. Rosalem W, Rescala B, Teles RP, Fischer RG, Gustafsson A,Figueredo CM. Effect of non-surgical treatment on chronicand aggressive periodontitis: clinical, immunologic, andmicrobiologic findings. J Periodontol 2011: 82: 979–989.

172. Rudney JD, Chen R, Sedgewick GJ. Actinobacillus actino-mycetemcomitans, Porphyromonas gingivalis, and Tanne-rella forsythensis are components of a polymicrobialintracellular flora within human buccal cells. J Dent Res2005: 84: 59–63.

173. Ryder MI. The influence of smoking on host responsesin periodontal infections. Periodontol 2000 2007: 43: 267–277.

174. Sagan C, Salvador A, Dubreuil D, Poulet PP, Duffaut D,Brumpt I. Simultaneous determination of metronidazoleand spiramycin I in human plasma, saliva and gingivalcrevicular fluid by LC-MS/MS. J Pharm Biomed Anal 2005:38: 298–306.

175. Sakellari D, Goodson JM, Kolokotronis A, Konstantinidis A.Concentration of 3 tetracyclines in plasma, gingival crevicefluid and saliva. J Clin Periodontol 2000: 27: 53–60.

176. Sakellari D, Ioannidis I, Antoniadou M, Slini T, Konstantin-idis A. Clinical and microbiological effects of adjunctive,locally delivered chlorhexidine on patients with chronicperiodontitis. J Int Acad Periodontol 2010: 12: 20–26.

Feres et al.

184

177. Sampaio E, Rocha M, Figueiredo LC, Faveri M, Duarte PM,Gomes Lira EA, Feres M. Clinical and microbiologicaleffects of azithromycin in the treatment of generalizedchronic periodontitis: a randomized placebo-controlledclinical trial. J Clin Periodontol 2011: 38: 838–846.

178. Sch€onwald S, Gunjaca M, Kolacny-Babi�c L, Car V, GosevM. Comparison of azithromycin and erythromycin in thetreatment of atypical pneumonias. J Antimicrob Chemo-ther 1990: 25(Suppl. A): 123–126.

179. Sgolastra F, Gatto R, Petrucci A, Monaco A. Effectivenessof systemic amoxicillin/metronidazole as adjunctive ther-apy to scaling and root planing in the treatment of chronicperiodontitis: a systematic review and meta-analysis.J Periodontol 2012: 83: 1257–1269.

180. Sgolastra F, Petrucci A, Gatto R, Monaco A. Effectivenessof systemic amoxicillin/metronidazole as an adjunctivetherapy to full-mouth scaling and root planing in thetreatment of aggressive periodontitis: a systematic reviewand meta-analysis. J Periodontol 2012: 83: 731–743.

181. Shibli JA, Melo L, Ferrari DS, Figueiredo LC, Faveri M,Feres M. Composition of supra- and subgingival biofilm ofsubjects with healthy and diseased implants. Clin OralImplants Res 2008: 19: 975–982.

182. Shiloah J, Patters MR, Dean JW, Bland P, Toledo G. Thesurvival rate of Actinobacillus actinomycetemcomitans,Porphyromonas gingivalis, and Bacteroides forsythus fol-lowing 4 randomized treatment modalities. J Periodontol1997: 68: 720–728.

183. Sigusch B, Beier M, Klinger G, Pfister W, Glockmann E. A2-step non-surgical procedure and systemic antibiotics inthe treatment of rapidly progressive periodontitis. J Peri-odontol 2001: 72: 275–283.

184. Silva MP, Feres M, Sirotto TA, Soares GM, Mendes JA, Fa-veri M, Figueiredo LC. Clinical and microbiological bene-fits of metronidazole alone or with amoxicillin as adjunctsin the treatment of chronic periodontitis: a randomizedplacebo-controlled clinical trial. J Clin Periodontol 2011:38: 828–837.

185. Slots J. Human viruses in periodontitis. Periodontol 20002010: 53: 89–110.

186. Slots J. Selection of antimicrobial agents in periodontaltherapy. J Periodontal Res 2002: 37: 389–398.

187. Slots J. The predominant cultivable organisms in juvenileperiodontitis. Scand J Dent Res 1976: 84: 1–10.

188. Slots J, Feik D, Rams TE. Age and sex relationships of su-perinfecting microorganisms in periodontitis patients.Oral Microbiol Immunol 1990: 5: 305–308.

189. Slots J, Mashimo P, Levine MJ, Genco RJ. Periodontal ther-apy in humans. I. Microbiological and clinical effects of asingle course of periodontal scaling and root planing, andof adjunctive tetracycline therapy. J Periodontol 1979: 50:495–509.

190. Slots J, Rams TE. Antibiotics in periodontal therapy:advantages and disadvantages. J Clin Periodontol 1990: 17:479–493.

191. Slots J, Ting M. Systemic antibiotics in the treatment ofperiodontal disease. Periodontol 2000 2002: 28: 106–176.

192. Smith SR, Foyle DM, Daniels J, Joyston-Bechal S, SmalesFC, Sefton A, Williams J. A double-blind placebocontrolledtrial of azithromycin as an adjunct to non-surgical treat-ment of periodontitis in adults: clinical results. J Clin Peri-odontol 2002: 29: 54–61.

193. Socransky SS, Haffajee AD, Cugini MA, Smith C, Kent RLJr. Microbial complexes in subgingival plaque. J Clin Peri-odontol 1998: 25: 134–144.

194. Socransky SS, Haffajee AD. Dental biofilms: difficult thera-peutic targets. Periodontol 2000 2002: 28: 2–55.

195. Socransky SS, Haffajee AD, Dzink JL, Hillman JD. Associa-tions between microbial species in subgingival plaquesamples. Oral Microbiol Immunol 1988: 3: 1–7.

196. Socransky SS, Haffajee AD, Dzink JL. Relationship of sub-gingival microbial complexes to clinical features at thesampled sites. J Clin Periodontol 1988: 15: 440–444.

197. Socransky SS, Haffajee AD. Evidence of bacterial etiology:a historical perspective. Periodontol 2000 1994: 5: 7–25.

198. Socransky SS, Haffajee AD. Periodontal microbial ecology.Periodontol 2000 2005: 38: 135–187.

199. Socransky SS, Haffajee AD, Smith C, Dibart S. Relation ofcounts of microbial species to clinical status at the samplesites. J Clin Periodontol 1991: 18: 766–775.

200. Socransky SS, Haffajee AD. The nature of periodontal dis-eases. Ann Periodontol 1997: 2: 3–10.

201. Socransky SS, Haffajee AD, Ximenez-Fyvie LA, Feres M,Mager D. Ecological considerations in the treatment ofActinobacillus actinomycetemcomitans and Porphyromon-as gingivalis periodontal infections. Periodontol 2000 1999:20: 341–362.

202. S€oder B, Nedlich U, Jin LJ. Longitudinal effect of non-sur-gical treatment and systemic metronidazole for 1 week insmokers and non-smokers with refractory periodontitis: a5-year study. J Periodontol 1999: 70: 761–771.

203. Somayaji BV, Jariwala U, Jayachandran P, Vidyalakshmi K,Dudhani RV. Evaluation of antimicrobial efficacy andrelease pattern of tetracycline and metronidazole using alocal delivery system. J Periodontol 1998: 69: 409–413.

204. Soskolne WA, Heasman PA, Stabholz A, Smart GJ, PalmerM, Flashner M, Newman HN. Sustained local delivery ofchlorhexidine in the treatment of periodontitis: amulti-center study. J Periodontol 1997: 68: 32–38.

205. Sun J, Song X, Kristiansen BE, Kjaereng A, Willems RJ, Erik-sen HM, Sundsfjord A, Sollid JE. Occurrence, populationstructure, and antimicrobial resistance of enterococci inmarginal and apical periodontitis. J Clin Microbiol 2009:47: 2218–2225.

206. Teixeira SR, Mattarazo F, Feres M, Figueiredo LC, de Fa-veri M, Simionato MR, Mayer MP. Quantification of Por-phyromonas gingivalis and fimA genotypes in smokerchronic periodontitis. J Clin Periodontol 2009: 36: 482–487.

207. Teles RP, Gursky LC, Faveri M, Rosa EA, Teles FR, Feres M,Socransky SS, Haffajee AD. Relationships between subgin-gival microbiota and GCF biomarkers in generalizedaggressive periodontitis. J Clin Periodontol 2010: 37: 313–323.

208. Teles RP, Haffajee AD, Socransky SS. Microbiological goalsof periodontal therapy. Periodontol 2000 2006: 42: 180–218.

209. Teles RP, Teles FR, Loesche WJ, Listgarten M, Fine D, Lind-he J, Malament K, Haffajee AD. Rediscovering Sig Socran-sky, the genius and his legacy. J Dent Res 2012: 91: 433–439.

210. van Winkelhoff AJ, Herrera Gonzales D, Winkel EG, Delle-mijn-Kippuw N, Vandenbroucke-Grauls CM, Sanz M. Anti-microbial resistance in the subgingival microflora inpatients with adult periodontitis. A comparison between


185

The Netherlands and Spain. J Clin Periodontol 2000: 27:79–86.

211. van Winkelhoff AJ, Rodenburg JP, Goen�e RJ, Abbas F,Winkel EG, de Graaff J. Metronidazole plus amoxycillin inthe treatment of Actinobacillus actinomycetemcomitansassociated periodontitis. J Clin Periodontol 1989: 16: 128–131.

212. Varela VM, Heller D, Silva-Senem MX, Torres MC, Co-lombo AP, Feres-Filho EJ. Systemic antimicrobials adjunc-tive to a repeated mechanical and antiseptic therapy foraggressive periodontitis: a 6-month randomized con-trolled trial. J Periodontol 2011: 82: 1121–1130.

213. Watanabe K, Frommel TO. Detection of Porphyromonasgingivalis in oral plaque samples by use of the polymerasechain reaction. J Dent Res 1993: 72: 1040–1044.

214. Winkel EG, van Winkelhoff AJ, Timmerman MF, van derVelden U, van der Weijden GA. Amoxicillin plus metroni-dazole in the treatment of adult periodontitis patients. Adouble-blind placebo-controlled study. J Clin Periodontol2001: 28: 296–305.

215. Xajigeorgiou C, Sakellari D, Slini T, Baka A, KonstantinidisA. Clinical and microbiological effects of different antimi-crobials on generalized aggressive periodontitis. J Period-ontol 2006: 33: 254–264.

216. Ximenez-Fyvie LA, Almaguer-Flores A, Jacobo-Soto V,Lara-Cordoba M, Sanchez-Vargas LO, Alcantara-Maruri E.Description of the subgingival microbiota of periodontallyuntreated Mexican subjects: chronic periodontitis andperiodontal health. J Periodontol 2006: 77: 460–471.

217. Ximenez-Fyvie LA, Haffajee AD, Socransky SS. Compari-son of the microbiota of supra- and subgingival plaque in

health and periodontitis. J Clin Periodontol 2000: 27: 648–657.

218. Xim�enez-Fyvie LA, Haffajee AD, Socransky SS. Microbialcomposition of supra- and subgingival plaque in subjectswith adult periodontitis. J Clin Periodontol 2000: 27: 722–732.

219. Yang HW, Asikainen S, Dogan B, Suda R, Lai CH. Relation-ship of Actinobacillus actinomycetemcomitans serotype bto aggressive periodontitis: frequency in pure cultured iso-lates. J Periodontol 2004: 75: 592–599.

220. Yashima A, Gomi k, Maeda N, Arai T. One-stagefull-mouth versus partial-mouth scaling and root planingduring the effective half-life of systemically administeredazithromycin. J Periodontol 2009: 80: 1406–1413.

221. Yek EC, Cintan S, Topcuoglu N, Kulekci G, Issever H, Kant-arci A. Efficacy of amoxicillin and metronidazole combina-tion for the management of generalized aggressiveperiodontitis. J Periodontol 2010: 81: 964–974.

222. Zambon JJ, Slots J, Genco RJ. Serology of oral Actinobacil-lus actinomycetemcomitans and serotype distribution inhuman periodontal disease. Infect Immun 1983: 41: 19–27.

223. Zandbergen D, Slot DE, Cobb CM, Van der Weijden FA.The clinical effect of scaling and root planing and the con-comitant administration of systemic amoxicillin and met-ronidazole: a systematic review. J Periodontol 2013: 84:332–351.

224. Zappa U, Reinking-Zappa M, Graf H, Gm€ur R, Savitt E.Comparison of serological and DNA probe analyses fordetection of suspected periodontal pathogens in subgingi-val plaque samples. Arch Oral Biol 1990: 35(Suppl.): 161S–164S.

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