Pursuing new periodontal pathogens with an improved RNA-oligonucleotide quantification technique (ROQT).

OBJECTIVE: The aim of this study was to optimize the sensitivity, specificity and cost-effectiveness of the RNA-Oligonucleotide Quantification Technique (ROQT) in order to identify periodontal pathogens that remain unrecognized or uncultured in the oral microbiome. DESIGN: Total nucleic acids (TNA) were extracted from subgingival biofilm samples using an automated process. RNA, DNA and Locked Nucleic Acid (LNA) digoxigenin-labeled oligonucleotide probes targeting 5 cultivated/named species and 16 uncultivated or unnamed bacterial taxa were synthesized. Probe specificity was determined by targeting 96 oral bacterial species; sensitivity was assessed using serial dilutions of reference bacterial strains. Different stringency temperatures were compared and new standards were tested. The tested conditions were evaluated analyzing samples from periodontally healthy individuals, and patients with moderate or severe periodontitis. RESULTS: The automated extraction method at 63°C along with LNA-oligunucleotides probes, and use of reverse RNA sequences for standards yielded stronger signals without cross-reactions. In the pilot clinical study, the most commonly detected uncultivated/unrecognized species were Selenomonas sp. HMT 134, Prevotella sp. HMT 306, Desulfobulbus sp. HMT 041, Synergistetes sp. HMT 360 and Bacteroidetes HMT 274. In the cultivated segment of the microbiota, the most abundant taxa were T. forsythia HMT 613 and Fretibacterium fastidiosum (formerly Synergistetes) HMT 363. CONCLUSIONS: In general, samples from severe patients had the greatest levels of organisms. Classic (T. forsythia, P. gingivalis) and newly proposed (F. alocis and Desulfobulbus sp. HMT 041) pathogens were present in greater amounts in samples from severe periodontitis sites, followed by moderate periodontitis sites.

Response to comment on "Aggregatibacter actinomycetemcomitans-induced hypercitrullination links periodontal infection to autoimmunity in rheumatoid arthritis".

Antibodies to leukotoxin A are markers that link Aggregatibacter actinomycetemcomitans-associated periodontitis and rheumatoid arthritis.

Exploring the microbiome of healthy and diseased peri-implant sites using Illumina sequencing.

AIM: To compare the microbiome of healthy (H) and diseased (P) peri-implant sites and determine the core peri-implant microbiome. MATERIALS AND METHODS: Submucosal biofilms from 32 H and 35 P sites were analysed using 16S rRNA sequencing (MiSeq, Illumina), QIIME and HOMINGS. Differences between groups were determined using principal coordinate analysis (PCoA), t tests and Wilcoxon rank sum test and FDR-adjusted. The peri-implant core microbiome was determined. RESULTS: PCoA showed partitioning between H and P at all taxonomic levels. Bacteroidetes, Spirochetes and Synergistetes were higher in P, while Actinobacteria prevailed in H (p < .05). Porphyromonas and Treponema were more abundant in P while Rothia and Neisseria were higher in H (p < .05). The core peri-implant microbiome contained Fusobacterium, Parvimonas and Campylobacter sp. T. denticola, and P. gingivalis levels were higher in P, as well as F. alocis, F. fastidiosum and T. maltophilum (p < .05). CONCLUSION: The peri-implantitis microbiome is commensal-depleted and pathogen-enriched, harbouring traditional and new pathogens. The core peri-implant microbiome harbours taxa from genera often associated with periodontal inflammation.

Low Biofilm Lysine Content in Refractory Chronic Periodontitis.

BACKGROUND: Chronic periodontitis is controlled without antibiotics by scaling and root planing (SRP) to remove dental biofilm. It has been previously reported that the epithelial barrier to bacterial proinflammatory products is impaired when biofilm lysine falls below the minimal content of normal blood plasma. Aims were to examine whether being refractory and requiring antibiotics to supplement SRP were associated with low biofilm lysine contents. METHODS: Sixteen patients with periodontitis and six periodontally healthy volunteers (HVs) (respective mean ages: 57 ± 6 and 36 ± 8 years) were examined. Patients with periodontitis received SRP and surgery, and HVs received prophylaxis. At quarterly maintenance or prophylaxis visits during the subsequent year, therapeutic response was good (GR, n = 9) or poor (PR, n = 7; including five cigarette smokers). Biofilm cadaverine, lysine, and other amino acid (AA) contents were determined by liquid chromatography. Cadaverine mole fraction of lysine plus cadaverine (CF) indicated biofilm lysine decarboxylase activity. RESULTS: Biofilm lysine was 0.19 ± 0.10 and 0.20 ± 0.09 µmol/mg in GRs and HVs, but 0.07 ± 0.03 µmol/mg in PRs (Kruskal-Wallis: P <0.01). All AAs were depleted in biofilm from smokers, but only lysine was depleted in biofilm from non-smokers. CF was inversely associated with clinical attachment level (CAL) at baseline before therapy in all patients (R2 = 0.28, P <0.01) and with CAL change after therapy in GR (R2 = 0.49, P <0.05). Lysine and cadaverine contents discriminated PRs from GRs and HVs (Wilks' λ = 0.499, P <0.012). CONCLUSIONS: Refractory responses requiring antibiotic therapy result from smoking and/or microbial infections that starve the biofilm and epithelial attachment of lysine. Biofilm CF is associated with periodontitis severity pretherapy and extent of therapeutic response post-therapy.

Aggregatibacter actinomycetemcomitans-induced hypercitrullination links periodontal infection to autoimmunity in rheumatoid arthritis.

A bacterial etiology of rheumatoid arthritis (RA) has been suspected since the beginnings of modern germ theory. Recent studies implicate mucosal surfaces as sites of disease initiation. The common occurrence of periodontal dysbiosis in RA suggests that oral pathogens may trigger the production of disease-specific autoantibodies and arthritis in susceptible individuals. We used mass spectrometry to define the microbial composition and antigenic repertoire of gingival crevicular fluid in patients with periodontal disease and healthy controls. Periodontitis was characterized by the presence of citrullinated autoantigens that are primary immune targets in RA. The citrullinome in periodontitis mirrored patterns of hypercitrullination observed in the rheumatoid joint, implicating this mucosal site in RA pathogenesis. Proteomic signatures of several microbial species were detected in hypercitrullinated periodontitis samples. Among these, Aggregatibacter actinomycetemcomitans (Aa), but not other candidate pathogens, induced hypercitrullination in host neutrophils. We identified the pore-forming toxin leukotoxin A (LtxA) as the molecular mechanism by which Aa triggers dysregulated activation of citrullinating enzymes in neutrophils, mimicking membranolytic pathways that sustain autoantigen citrullination in the RA joint. Moreover, LtxA induced changes in neutrophil morphology mimicking extracellular trap formation, thereby releasing the hypercitrullinated cargo. Exposure to leukotoxic Aa strains was confirmed in patients with RA and was associated with both anticitrullinated protein antibodies and rheumatoid factor. The effect of human lymphocyte antigen-DRB1 shared epitope alleles on autoantibody positivity was limited to RA patients who were exposed to Aa These studies identify the periodontal pathogen Aa as a candidate bacterial trigger of autoimmunity in RA.

Effects of triclosan on host response and microbial biomarkers during experimental gingivitis.

AIM: This exploratory randomized, controlled clinical trial sought to evaluate anti-inflammatory and -microbial effects of triclosan during experimental gingivitis as assessed by host response biomarkers and biofilm microbial pathogens. MATERIALS AND METHODS: Thirty participants were randomized to triclosan or control dentifrice groups who ceased homecare for 21 days in an experimental gingivitis (EG) protocol. Plaque and gingival indices and saliva, plaque, and gingival crevicular fluid (GCF) were assessed/collected at days 0, 14, 21 and 35. Levels and proportions of 40 bacterial species from plaque samples were determined using checkerboard DNA-DNA hybridization. Ten biomarkers associated with inflammation, matrix degradation, and host protection were measured from GCF and saliva and analysed using a multiplex array. Participants were stratified as "high" or "low" responders based on gingival index and GCF biomarkers and bacterial biofilm were combined to generate receiver operating characteristic curves and predict gingivitis susceptibility. RESULTS: No differences in mean PI and GI values were observed between groups and non-significant trends of reduction of host response biomarkers with triclosan treatment. Triclosan significantly reduced levels of A. actinomycetemcomitans and P. gingivalis during induction of gingivitis. CONCLUSIONS: Triclosan reduced microbial levels during gingivitis development (ClinicalTrials.gov NCT01799226).

Periodontal bone loss and risk of epithelial ovarian cancer.

PURPOSE: Periodontitis, a chronic inflammatory response to pathogenic bacteria in the oral microbiome, is common among adults. It is associated with several medical conditions, including cardiovascular diseases, and potentially with esophageal, lung, oral, and pancreatic cancer. One of the proposed mechanisms behind these associations is systemic inflammation, which has also been implicated in ovarian cancer etiology. The aim of this study was to evaluate association between ovarian cancer and periodontal bone loss. METHODS: The association between periodontal bone loss, a marker of periodontitis, and risk of epithelial ovarian cancer was estimated among 60,560 participants of the prospective Nurses' Health Study using Cox proportional hazards analysis. Competing risks analysis was used to estimate association by histologic subtype. RESULTS: We did not observe an increased risk of ovarian cancer among participants with periodontal bone loss (HR 0.86, 95% CI 0.64-1.15). Among women younger than 69 years, periodontal bone loss was associated with a 40 % (HR 0.60, 95% CI 0.36-0.98) decreased ovarian cancer risk, while there was no association in women older than 69 (HR 1.09, 95% CI 0.75-1.58), although this difference did not reach statistical significance (p-heterogeneity = 0.06). We observed a suggestive decreased risk for serous tumors (HR 0.76, 95% CI 0.53-1.09). The number of natural teeth and root canals, other metrics of oral health, were not associated with ovarian cancer risk. CONCLUSION: Our results do not support an increased ovarian cancer risk in women with periodontal bone loss; however, there was a significant decrease in risk in women younger than 69. Given the unexpected association between periodontal bone loss and ovarian cancer risk in younger women, further research is warranted.

Levels of gingival crevicular fluid matrix metalloproteinases in periodontally compromised teeth under orthodontic forces.

OBJECTIVE: To examine levels of matrix metalloproteinases (MMPs)-1, -2, -3, -7, -8, -12, and -13 in the gingival crevicular fluid (GCF) of periodontally compromised teeth at different time points during orthodontic movement. MATERIALS AND METHODS: Ten controlled periodontitis subjects were submitted to orthodontic treatment. One dental arch was subjected to orthodontic movement, and teeth in the opposite arch were used as controls. GCF samples were collected from the lingual sites of two movement and two control incisors 1 week before orthodontic activation (-7 d), immediately after orthodontic activation, and after 1 hour, 24 hours, and 7, 14, and 21 days. Multiplexed bead immunoassay was used to measure MMPs in GCF. Data were analyzed using Friedman and Wilcoxon statistical tests. RESULTS: The only significant change found over time was in the levels of MMP-1 in the movement group (P < .05). When the two groups were compared after activation, the only statistically significant difference found was in levels of MMP-12 24 hours after activation (P < .05). CONCLUSIONS: Our findings suggested that the orthodontic movement of periodontally compromised teeth without active pockets did not result in significant changes in the GCF levels of MMPs.

The effects of adjunctive metronidazole plus amoxicillin in the treatment of generalized aggressive periodontitis: a 1-year double-blinded, placebo-controlled, randomized clinical trial.

AIM: To evaluate the clinical effects of the adjunctive use of metronidazole (MTZ) and amoxicillin (AMX) in the treatment of generalized aggressive periodontitis (GAgP). METHODS: Thirty subjects were randomly assigned to receive scaling and root planing (SRP) alone or combined with MTZ (400 mg/TID) and AMX (500 mg/TID) for 14 days. Subjects were clinically monitored at baseline, 6 months and 1 year post-therapies. RESULTS: Both therapies led to a statistically significant improvement in all clinical parameters at 1 year post-therapy (p < 0.05). Subjects receiving MTZ plus AMX exhibited the deepest reductions in mean probing depth (PD) and gain in clinical attachment between baseline and 1 year post-therapy in the full-mouth analysis and in initially intermediate (PD 4-6 mm) and deep (PD ≥ 7 mm) sites (p < 0.01). In addition, the antibiotic group presented lower mean number of residual sites with PD ≥ 5 or 6 mm as well as fewer subjects still presenting nine or more sites with PD ≥ 5 mm or three or more sites with PD ≥ 6 mm at the end of the study period. CONCLUSION: The non-surgical treatment of GAgP is markedly improved by the adjunctive use of MTZ+AMX, up to 1 year post-treatment.

Bacterial and salivary biomarkers predict the gingival inflammatory profile.

BACKGROUND: The aim of this human investigation is to explore the relationship of gingivitis with salivary biomarkers, periodontal pathogens, and interleukin (IL)-1 polymorphism after a transient inflammatory burden. METHODS: Thirty healthy human participants were randomized by IL-1 genotype status to control for potential influences of this particular single nucleotide polymorphism on the inflammatory profile. Oral hygiene practices ceased for 21 days to induce gingivitis (induction), after which home care was reinstated until 35 days (resolution). Clinical parameters included plaque (PI) and gingival (GI) indices and papillary bleeding score (PBS). Levels and proportions of 40 subgingival bacteria were determined using checkerboard DNA-DNA hybridization. Saliva was analyzed using a multiplex protein array for 30 biomarkers associated with host defense, inflammation, tissue destruction, and angiogenesis. RESULTS: Mean PI, GI, and PBS values were significantly increased during induction and decreased during resolution as measured at 35 days (P <0.01), although no differences were observed between IL-1 groups. Participants were stratified as either "high" or "low" responders based on inflammatory response (high: GI >1.5; low: GI ≤1.5). Baseline levels of salivary IL-6 and IL-8 demonstrated the highest ability to discriminate between high and low responders (area under the curve [AUC] of 0.81 and 0.72, respectively). Salivary biomarkers, matrix metalloproteinases (MMPs), and bacterial biofilm were combined to generate receiver operating characteristic curves. High levels of IL-6 and MMP-1 at baseline demonstrated the strongest ability to predict high responders (AUC of 0.89; odds ratio of 17.0; 95% confidence interval, 1.7 to 171.7). CONCLUSION: In this proof-of-concept investigation, we identified specific biomarker and microbial signatures that are associated with gingival inflammation (ClinicalTrials.gov number NCT00980525).

Relationships among interleukin-6, tumor necrosis factor-α, adipokines, vitamin D, and chronic periodontitis.

BACKGROUND: The aim of this study is to explore relationships among serum adipokines, vitamin D, and clinical and microbial parameters of chronic periodontitis before and after treatment. METHODS: Weight, height, and smoking status were recorded for 56 patients with chronic periodontitis. Plaque, gingivitis, bleeding on probing, suppuration, probing depth, and clinical attachment level were measured at all teeth present. Subgingival biofilm samples from each tooth were analyzed for levels of 40 bacterial species using checkerboard DNA-DNA hybridization. Serum levels of interleukin-6 (IL-6), tumor necrosis factor-α, adiponectin, leptin, resistin, and vitamin D were measured at baseline. Sample collection was then performed in a subset of the population 6 months after therapy (n = 17). Serum samples were analyzed using enzyme-linked immunosorbent assay and immunoassays. Differences in clinical, microbial, and serum factors among groups were sought using the Mann-Whitney U test. Correlations among factors were evaluated using regression analysis. Effects of therapy were sought using the Wilcoxon signed rank test. RESULTS: There were positive correlations between adiponectin/vitamin D and between IL-6/leptin, negative correlations between IL-6/vitamin D and leptin/vitamin D, but no associations between serum analytes and clinical or microbial parameters. Sex and body mass index were associated with levels of adipokines. Periodontal therapy improved clinical and microbiologic parameters but did not influence the levels of serum analytes. CONCLUSION: Adipokines and IL-6 levels were affected by sex and body mass index. Serum analytes were not influenced by periodontal therapy.

Microbial shifts during dental biofilm re-development in the absence of oral hygiene in periodontal health and disease.

AIM: To monitor microbial shifts during dental biofilm re-development. MATERIALS AND METHODS: Supra- and subgingival plaque samples were taken separately from 28 teeth in 38 healthy and 17 periodontitis subjects at baseline and immediately after tooth cleaning. Samples were taken again from seven teeth in randomly selected quadrants during 1, 2, 4 and 7 days of no oral hygiene. Samples were analysed using checkerboard DNA-DNA hybridization. Species counts were averaged within subjects at each time point. Significant differences in the counts between healthy and periodontitis subjects were determined using the Mann-Whitney test. RESULTS: The total supra- and subgingival counts were significantly higher in periodontitis on entry and reached or exceeded the baseline values after day 2. Supragingival counts of Veillonella parvula, Fusobacterium nucleatum ss vincentii and Neisseria mucosa increased from 2 to 7 days. Subgingival counts were greater for Actinomyces, green and orange complex species. Significant differences between groups in supragingival counts occurred for 17 of 41 species at entry, 0 at day 7; for subgingival plaque, these values were 39/41 taxa at entry, 17/41 at day 7. CONCLUSIONS: Supragingival plaque re-development was similar in periodontitis and health, but subgingival species recolonization was more marked in periodontitis.

Relationships between subgingival microbiota and GCF biomarkers in generalized aggressive periodontitis.

AIM: To examine relationships between subgingival biofilm composition and levels of gingival crevicular fluid (GCF) cytokines in periodontal health and generalized aggressive periodontitis (GAP). MATERIALS AND METHODS: Periodontal parameters were measured in 25 periodontally healthy and 31 GAP subjects. Subgingival plaque and GCF samples were obtained from 14 sites from each subject. Forty subgingival taxa were quantified using checkerboard DNA-DNA hybridization and the concentrations of eight GCF cytokines were measured using Luminex. Cluster analysis was used to define sites with similar subgingival microbiotas in each clinical group. Significance of differences in clinical, microbiological and immunological parameters among clusters was determined using the Kruskal-Wallis test. RESULTS: GAP subjects had statistically significantly higher GCF levels of interleukin-1beta (IL-1beta) (p<0.001), granulocyte-macrophage colony-stimulating factor (GM-CSF) (p<0.01) and IL-1beta/IL-10 ratio (p<0.001) and higher proportions of Red and Orange complex species than periodontally healthy subjects. There were no statistically significant differences in the mean proportion of cytokines among clusters in the periodontally healthy subjects, while the ratio IL-1beta/IL-10 (p<0.05) differed significantly among clusters in the aggressive periodontitis group. CONCLUSIONS: Different subgingival biofilm profiles are associated with distinct patterns of GCF cytokine expression. Aggressive periodontitis subjects were characterized by a higher IL-1beta/IL-10 ratio than periodontally healthy subjects, suggesting an imbalance between pro- and anti-inflammatory cytokines in aggressive periodontitis.

Immunologic and microbiologic profiles of chronic and aggressive periodontitis subjects.

BACKGROUND: This study determines the gingival crevicular fluid (GCF) levels of interleukin (IL)-1 beta, IL-2, IL-4, IL-8, interferon (IFN)-gamma and elastase activity in inflamed shallow and deep periodontal sites from patients with generalized chronic (GCP) and generalized aggressive periodontitis (GAgP), and to compare them to shallow sites from subjects with gingivitis. A secondary aim analyzes the microbiologic profile of these subjects. METHODS: Cross-sectional clinical data were obtained from 20 GCP, 17 GAgP, and 10 gingivitis subjects. GCF samples were collected with paper strips and the levels of IL-1 beta, IL-2, IL-4, IL-8, and IFN-gamma were measured using a multiplexed bead immunoassay. Elastase activity was assessed by an enzymatic assay. Subgingival plaque samples were analyzed using checkerboard DNA-DNA hybridization. Significance of differences among groups for immunologic and microbiologic data was examined using Kruskal-Wallis adjusting for multiple comparisons. RESULTS: Mean clinical parameters and GCF volumes were higher in patients with GCP and GAgP compared to the gingivitis group. Higher levels of IL-1 beta and higher elastase activity were found in deep sites compared to shallow sites in both periodontitis groups (P <0.05). The microbiologic data showed significantly higher levels of the red complex species in patients with GCP and GAgP compared to gingivitis (P <0.05). There were no statistically significant differences in levels of GCF biomarkers and in levels of subgingival bacterial species between subjects with GCP and GAgP. CONCLUSION: There were no statistically significant differences in the measured immunologic and microbiologic parameters between subjects with GCP and GAgP.

The microbiota associated with implants restored with platform switching: a preliminary report.

BACKGROUND: It was demonstrated that implants restored according to a platform-switching concept presented less crestal bone loss than implants restored with standard protocols. The aim of this study is to examine differences between the composition of the peri-implant microbiotas associated with implants restored with the platform-switching approach and implants restored with a standard internal connection protocol. METHODS: A total of 48 implants were examined in 18 subjects: 33 implants were restored with platform switching, and 15 implants were restored using the traditional approach. Thirty-six months after prosthetic loading, subgingival plaque samples were taken from the mesio- and disto-buccal aspects of each implant and from one tooth adjacent to one of the implants in each subject. The levels of 40 subgingival species were measured using checkerboard DNA-DNA hybridization. Microbiologic parameters were averaged within each subject and across subjects in each clinical group (platform switching versus control) and site category (implants versus teeth) separately. The significance of differences between clinical groups and site categories was determined using the Mann-Whitney test and the Wilcoxon test, respectively. RESULTS: There were no statistically significant differences between groups for any of the species. The platform-switching group showed a small trend for lower levels of early colonizer members of the Actinomyces, purple and yellow complexes, Campylobacter species, Tannerella forsythia (previously T. forsythensis), and Porphyromonas gingivalis. Teeth and implants presented similar microbial profiles. CONCLUSION: The results of the study suggest that the difference in bone crest resorption between implants restored with platform switching compared to traditionally restored implants is not associated with differences in the peri-implant microbiota.

Application of the checkerboard immunoblotting technique to the quantification of host biomarkers in gingival crevicular fluid.

BACKGROUND: The aim of this study was to describe the development and validation of the checkerboard immunoblotting (CBIB) technique for the high-throughput quantification of multiple inflammatory mediators in gingival crevicular fluid (GCF) samples. METHODS: Monoclonal antibodies were used to bind GCF interleukin (IL)-1beta and -8 and matrix metalloproteinase (MMP)-8 to the surface of membranes. Biotinylated antibodies were used to detect bound antigens in a checkerboard format. Signals were developed using chemiluminescence, captured on film, and quantified using software for array analysis. The assay was tested for potential cross-reactions among the three pairs of antibodies. Eleven CBIBs were processed to determine the analytical sensitivity of the assay. Forty GCF samples were analyzed using CBIB and enzyme-linked immunosorbent assay (ELISA) in parallel, and the significance of the correlations among the results was tested using the Pearson correlation coefficient. Nine hundred thirty-one GCF samples were collected from 20 periodontally healthy subjects and 20 periodontitis subjects and analyzed using CBIB to test the assay's sensitivity and dynamic ranges using clinical samples. RESULTS: The CBIB was capable of distinguishing among the three analytes. The sensitivity and dynamic ranges of the assay were suitable for the detection of the three targets in the majority of GCF samples. There were highly statistically significant (P <0.0001) positive correlations between CBIB and ELISA data for all three biomarkers. The periodontitis subjects had statistically significantly higher mean levels of IL-1beta and -8 compared to healthy subjects. CONCLUSION: The CBIB technique is a sensitive and specific assay for the high-throughput quantification of MMP-8 and IL-8 and -1beta in GCF.

Effect of herbal, essential oil, and chlorhexidine mouthrinses on the composition of the subgingival microbiota and clinical periodontal parameters.

OBJECTIVE: The purpose of the present investigation was to determine if antimicrobial mouthrinses with different formulations could affect the composition of the subgingival microbiota and clinical parameters of adjacent tissues in periodontal maintenance subjects. METHODS: One-hundred and sixteen subjects, who had been treated for chronic periodontitis and were in a maintenance program, were randomly assigned one of four mouthrinses, to be used twice daily for three months. The mouthrinses were herbal 1, herbal 2, essential oil, and chlorhexidine. Clinical measurements and subgingival plaque samples were taken at baseline and at three months. Plaque samples were individually evaluated for 18 test species/taxa using checkerboard DNA-DNA hybridization. Significance of differences between baseline and three months for both microbiological and clinical parameters were determined using the Wilcoxon Signed Ranks test. Significance of difference among groups for change in clinical and microbiological parameters was determined using analysis of covariance (ANCOVA), adjusting for baseline values. RESULTS: Shifts in species proportions differed significantly for 9/18 test species/taxa among the four mouthrinse groups. Streptococcus and Capnocytophaga species were reduced most in the herbal rinse groups, while Veillonella parvula was reduced most in the essential oil and chlorhexidine groups. Actinomyces were also markedly reduced in the chlorhexidine group. Mean Plaque (PI) and Gingival Indices (GI) were reduced between baseline and three months in each group. Results emphasize that chlorhexidine (p < 0.001) and herbal (p < 0.05) rinses significantly reduced PI. Some subjects in each group responded better than others. CONCLUSION: All four mouthrinses tested produced shifts in the composition of subgingival microbiota, although the results differed among the groups. The observed microbial changes were accompanied by improvements in clinical parameters in the periodontal maintenance subjects.

Locally delivered doxycycline during supportive periodontal therapy: a 3-year study.

BACKGROUND: Adjunctive locally delivered antibiotics during maintenance may favor the control of periodontal infections. This study evaluated the long-term clinical and microbiologic effects of yearly locally delivered controlled-release doxycycline as an adjunct to mechanical debridement. METHODS: A total of 128 periodontal maintenance patients having at least four teeth with probing depth (PD) > or =5 mm were randomly assigned to local application of doxycycline gel at baseline and 1 and 2 years as an adjunct to mechanical debridement (test) or mechanical debridement only (control). Supportive periodontal therapy (mechanical debridement, polishing, and oral hygiene reinforcement) was provided every 6 months. Plaque, bleeding on probing (BOP), PD, and relative attachment level (RAL) were scored at baseline; 3 months; and 1, 2, and 3 years. Subgingival plaque samples were taken at each examination and analyzed for their content of 40 bacterial species. Data analyses were performed on an intention-to-treat basis with the subject as the statistical unit. RESULTS: Significant reductions in BOP, PD, RAL, and the mean counts of a number of target species between baseline and 3 years were documented for both treatment groups, whereas plaque scores remained unchanged. A statistically significant difference in favor of the adjunctive doxycycline therapy was found between the two groups only at the 3-month examination for BOP, PD, and RAL and for a minority of bacterial species at 2 years. CONCLUSION: Although short-term effects on clinical parameters were found with the adjunctive use of locally delivered doxycycline, repeated applications annually had no clinical or microbiologic effects beyond those observed with mechanical debridement alone in maintenance patients.

Long-term effect of the combined use of powered toothbrush and triclosan dentifrice in periodontal maintenance patients.

AIM: To test the hypothesis of a superior clinical and microbiological effect of the combined use of powered toothbrush+triclosan-containing dentifrice compared with manual toothbrush+regular fluoride-containing dentifrice in periodontal maintenance patients. MATERIAL AND METHODS: A total of 128 periodontitis subjects involved in recall programmes were randomized to use either powered toothbrush with triclosan-dentifrice (test) or manual toothbrush and standard dentifrice (control). Supportive periodontal treatment was provided at baseline and every 6 months. Plaque, bleeding on probing (BoP), probing pocket depth (PPD) and relative attachment level (RAL) were scored at baseline, 1, 2 and 3 years. Subgingival plaque samples were taken and analysed for their content of 40 bacterial species at each examination interval. All analyses were performed by "intention-to-treat" protocol. RESULTS: Both groups showed significant reduction in BoP, PPD and in mean total counts of the 40 bacterial species between baseline and 3 years, while plaque score and RAL remained almost unchanged. No significant differences between the two prevention programmes were found for any of the clinical outcome variables or in mean counts of the various bacterial species. CONCLUSIONS: The study failed to demonstrate superior clinical and microbiological effects of powered toothbrush+triclosan dentifrice compared with manual toothbrush+standard fluoride-dentifrice in periodontitis-susceptible patients on regular maintenance therapy.

Clinical and microbiologic changes associated with the combined use of a powered toothbrush and a triclosan/copolymer dentifrice: a 3-year prospective study.

BACKGROUND: Different means are available for self-performed oral hygiene. The aim of this study was to evaluate the clinical and microbiologic effects of a preventive homecare program including the combined use of a powered toothbrush and a triclosan/copolymer-containing dentifrice. METHODS: A total of 160 adult subjects without signs of destructive periodontal disease were recruited for this 3-year randomized controlled trial. The subjects were assigned to a homecare program using an oscillating/rotating powered toothbrush and a triclosan/copolymer/fluoride-containing dentifrice (test) or a manual toothbrush and a standard fluoride-containing dentifrice (control). Supragingival polishing and reinforcement of homecare procedures were provided every 6 months. Plaque, bleeding on probing (BOP), and probing depth (PD) were scored at baseline and after 1, 2, and 3 years. Subgingival plaque samples were taken from the mesial aspect of each tooth at baseline and after 1, 2, and 3 years and were analyzed for their content of 40 bacterial species using checkerboard DNA-DNA hybridization. All data analyses were based on "intention-to-treat" with the subject as the statistical unit. RESULTS: Compared to baseline, no significant changes in clinical parameters were observed during the 3 years, except for a reduction in the mean PD at the 2- and 3-year follow-up examinations (P <0.05). No significant differences were found between the two groups with regard to plaque, BOP, or PD or in the mean counts of the 40 species at any time point. CONCLUSION: The study failed to prove additional benefits of the combined use of a powered toothbrush and a triclosan/copolymer-containing dentifrice in adult subjects without signs of destructive periodontal disease.