Subgingival biodiversity in subjects with uncontrolled type-2 diabetes and chronic periodontitis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Microbiota in the oral subgingival biofilm is associated with obesity in adolescence

To test the hypothesis whether microbiota in oral biofilm is linked with obesity in adolescents we designed this cross-sectional study. Obese adolescents (n = 29) with a mean age of 14.7 years and normal weight subjects (n = 58) matched by age and gender were examined with respect to visible plaque index (VPI%) and gingival inflammation (bleeding on probing (BOP%)). Stimulated saliva was collected. They answered a questionnaire concerning medical history, medication, oral hygiene habits, smoking habits, and sociodemographic background. Microbiological samples taken from the gingival crevice was analyzed by checkerboard DNA-DNA hybridization technique. The sum of bacterial cells in subgingival biofilm was significantly associated with obesity (P < 0.001). The link between sum of bacterial cells and obesity was not confounded by any of the studied variables (chronic disease, medication, VPI%, BOP%, flow rate of whole saliva, or meal frequency). Totally 23 bacterial species were present in approximately threefold higher amounts, on average, in obese subjects compared with normal weight controls. Of the Proteobacteria phylum, Campylobacter rectus and Neisseria mucosa were present in sixfold higher amounts among obese subjects. The association between obesity and sum of bacterial cells in oral subgingival biofilm indicates a possible link between oral microbiota and obesity in adolescents.

The Subgingival Microbiota in older subjects. Impact of Chlorhexidine Rinsing

Background: Periodontitis and caries are common diseases in older adults. Aims: To test if rinsing with chlorhexidine over five years has an impact on the subgingival microbiota. Methods: In a double blind randomized five years chlorhexidine rinse study clinical oral data and subgingival plaque samples were analyzed by the checkerboard DNA-DNA hybridization method. Results: At year 5 subject mean age was 71.2 years (S.D. + 4.1) (56.2% women). Only in subjects with no bone loss did the chlorhexidine rinse group subjects presented with lower total bacterial (DNA) counts (mean diff: 63.1 (x105), S.E diff + 30.1 (x105), 95%CI: 0.8 to 120.5 (x105), p<0.05) [(i.e.Lactobacillus acidophilicus (p<0.05) , Streptococcus oralis (p<0.05), Eikenella. corrodens (p< 0.05), C. gracilis (p<0.01), F.nucl.sp. nucleatum (p< 0.02), Fusobacterium nucl. sp. polymorphum (p<0.02), Neisseria mucosa (p<0.02), Leptothrichia buccalis (p<0.02), and Selenomonas noxia (p<0.050)]. Higher bacterial loads were found for the green (p<0.05), yellow (streptococci spp) (p<0.01), and the ‘other' complexes (p<0.01). Conclusions: Independent of probing pocket depth, older subjects carry a large variety of bacteria associated with periodontitis. The oral microbiota in older subjects is linked to alveolar bone loss and not to probing depth. Chlorhexidine may provide a benefit in preventing periodontitis in older persons.

The impact of a low-frequency chlorhexidine rinsing schedule on the subgingival microbiota (the TEETH clinical trial)

BACKGROUND: Information on the efficacy of chlorhexidine (CHX) rinsing on the subgingival microbiota is limited. This study tested if intermittent CHX rinsing over 5 years had an impact on the subgingival microbiota. METHODS: Subgingival plaque samples were analyzed by the checkerboard DNA-DNA hybridization method in a double-blind randomized CHX rinse study. RESULTS: A total of 210 subjects were included. The mean age of the subjects was 71.7 (+/- 4.1) years, and 56.2% were women. Evidence of alveolar bone loss was found in 39% of subjects. Bacterial loads were not correlated significantly with probing depth. At year 5, subjects in the CHX rinse group with no evidence of bone loss presented with lower total bacterial counts than control subjects with no bone loss. The levels of the following bacteria were significantly lower in the CHX group: Lactobacillus acidophilus (P <0.05), Eikenella corrodens (P <0.05), Fusobacterium nucleatum sp. nucleatum (P <0.01), Treponema denticola (P <0.05), Leptotrichia buccalis (P <0.05), and Eubacterium saburreum (P <0.05). No differences in bacterial loads were found between CHX and control rinse subjects with alveolar bone loss. CONCLUSIONS: Older subjects with or without periodontitis carry a large variety of bacteria associated with periodontitis. Intermittent rinsing with CHX may provide a preventive benefit in reducing levels of bacteria but only in subjects without alveolar bone loss.

Similarities in the Subgingival Microbiota Assessed by a Curet Sampling Method at Sites With Chronic Periodontitis

Background: The goal of this study was to determine whether site-specific differences in the subgingival microbiota could be detected by the checkerboard method in subjects with periodontitis. Methods: Subjects with at least six periodontal pockets with a probing depth (PD) between 5 and 7 mm were enrolled in the study. Subgingival plaque samples were collected with sterile curets by a single-stroke procedure at six selected periodontal sites from 161 subjects (966 subgingival sites). Subgingival bacterial samples were assayed with the checkerboard DNA-DNA hybridization method identifying 37 species. Results: Probing depths of 5, 6, and 7 mm were found at 50% (n = 483), 34% (n = 328), and 16% (n = 155) of sites, respectively. Statistical analysis failed to demonstrate differences in the sum of bacterial counts by tooth type (P = 0.18) or specific location of the sample (P = 0.78). With the exceptions of Campylobacter gracilis (P <0.001) and Actinomyces naeslundii (P <0.001), analysis by general linear model multivariate regression failed to identify subject or sample location factors as explanatory to microbiologic results. A trend of difference in bacterial load by tooth type was found for Prevotella nigrescens (P <0.01). At a cutoff level of >/=1.0 x 10(5), Porphyromonas gingivalis and Tannerella forsythia (previously T. forsythensis) were present at 48.0% to 56.3% and 46.0% to 51.2% of sampled sites, respectively. Conclusions: Given the similarities in the clinical evidence of periodontitis, the presence and levels of 37 species commonly studied in periodontitis are similar, with no differences between molar, premolar, and incisor/cuspid subgingival sites. This may facilitate microbiologic sampling strategies in subjects during periodontal therapy.

Tannerella forsythia and Pseudomonas aeruginosa in subgingival bacterial samples from parous women

BACKGROUND: Information on the subgingival microbiota in parous women is limited. The present study assessed 74 bacterial species at periodontal sites. METHODS: Subgingival bacterial plaque was collected from women > or =6 months after delivery. Bacteria were assessed by the checkerboard DNA-DNA hybridization method. Gingivitis was defined as > or =20% of sites with bleeding on probing (BOP), and periodontitis was defined as radiographic evidence of bone loss and probing depths > or =5.0 mm. RESULTS: A total of 197 women (mean age: 29.4 +/- 6.8 years; range: 18 to 46 years) were included in the study. Gingivitis was identified in 82 of 138 subjects without evidence of periodontitis (59.4%). Periodontitis was found in 59 women (32%). Higher bacterial levels in subjects with gingivitis compared to those without evidence of gingivitis were observed for Actinomyces neuii, Bifidobacterium bifidum, Corynebacterium pseudogenitalis, Porphyromonas endodontalis, Prevotella bivia, and Pseudomonas aeruginosa (P <0.001 for each). Higher bacterial levels in subjects with periodontitis compared to those without periodontitis (BOP not accounted for) were found for 32 of 79 species (P <0.001) including Lactobacillus iners, Haemophilus influenzae, Porphyromonas gingivalis, Tannerella forsythia (previously T. forsythensis), Prevotella bivia, P. aeruginosa, and Staphylococcus aureus. Binary univariate logistic regression analysis identified that P. aeruginosa (P <0.001) and T. forsythia (P <0.05) were independently predictive of periodontal status. The odds ratio of having P. aeruginosa at levels > or =1 x 10(5) in the sample and periodontitis was 3.1 (95% confidence interval: 1.6 to 5.9; P <0.001). CONCLUSION: In addition to P. gingivalis and T. forsythia, a diverse microbiota, including P. aeruginosa, P. endodontalis, P. bivia, and S. aureus, can be found in subgingival plaque samples from women of child-bearing age with periodontitis.

Comparison of visual-tactile, radiographic, and histologic diagnoses of subgingival crown margin caries- an in vitro study

The purpose of this study was to investigate the accuracy of diagnosing interproximal subgingival caries at crown margins. A total of 32 subgingival interproximal crown margin areas were examined by 10 clinicians (n = 320) using conventional diagnostic methods on extracted, crowned teeth mounted in a specially designed cast. Crown margins were located 1.5 mm below the level of the artificial gingiva. Clinical and radiographic diagnoses were compared to the histopathologic findings for each site. Both visual-tactile and radiographic evaluations revealed a weak diagnostic accuracy for interproximal subgingival crown margin caries.

Does pregnancy have an impact on the subgingival microbiota?

BACKGROUND: We investigated clinical and subgingival microbiologic changes during pregnancy in 20 consecutive pregnant women > or =18 years not receiving dental care. METHODS: Bacterial samples from weeks 12, 28, and 36 of pregnancy and at 4 to 6 weeks postpartum were processed for 37 species by checkerboard DNA-DNA hybridization. Clinical periodontal data were collected at week 12 and at 4 to 6 weeks postpartum, and bleeding on probing (BOP) was recorded at sites sampled at the four time points. RESULTS: The mean BOP at week 12 and postpartum was 40.1% +/- 18.2% and 27.4% +/- 12.5%, respectively. The corresponding mean BOP at microbiologic test sites was 15% (week 12) and 21% (postpartum; not statistically significant). Total bacterial counts decreased between week 12 and postpartum (P <0.01). Increased bacterial counts over time were found for Neisseria mucosa (P <0.001). Lower counts (P <0.001) were found for Capnocytophaga ochracea, Capnocytophaga sputigena, Eubacterium saburreum, Fusobacterium nucleatum naviforme, Fusobacterium nucleatum polymorphum, Leptotrichia buccalis, Parvimonas micra (previously Peptostreptococcus micros or Micromonas micros), Prevotella intermedia, Prevotella melaninogenica, Staphylococcus aureus, Streptococcus anginosus, Streptococcus intermedius, Streptococcus mutans, Streptococcus oralis, Streptococcus sanguinis, Selenomonas noxia, and Veillonella parvula. No changes occurred between weeks 12 and 28 of pregnancy. Counts of Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, Tannerella forsythia (previously T. forsythensis), and Treponema denticola did not change. Counts of P. gingivalis and T. forsythia at week 12 were associated with gingivitis (P <0.001). CONCLUSIONS: Subgingival levels of bacteria associated with periodontitis did not change. P. gingivalis and T. forsythia counts were associated with BOP at week 12. A decrease was found in 17 of 37 species from week 12 to postpartum. Only counts of N. mucosa increased.

Clinical outcomes following subgingival application of a novel erythritol powder by means of air polishing in supportive periodontal therapy: a randomized, controlled clinical study

OBJECTIVES The aim of this prospective, randomized, controlled clinical study was to compare the clinical outcomes of the subgingival treatment with erythritol powder by means of an air-polishing (EPAP) device and of scaling and root planing (SRP) during supportive periodontal therapy (SPT). METHOD AND MATERIALS 40 patients enrolled in SPT were randomly assigned to two groups of equal size. Sites had to show signs of inflammation (bleeding on probing [BOP]-positive) and a probing pocket depth (PPD) of ≥ 4 mm, however, without presence of detectable subgingival calculus. During SPT, these sites were treated with EPAP or SRP, respectively. Full mouth and site-specific plaque indices, BOP, PPD, and clinical attachment level (CAL) were recorded at baseline (BL) and at 3 months, whereas the percentage of study sites positive for BOP (BOP+) was considered as primary outcome variable. Additionally, patient comfort using a visual analog scale (VAS) and the time needed to treat per site was evaluated. RESULTS At 3 months, mean BOP level measured 45.1% at test sites and 50.6% at control sites, respectively, without a statistically significant difference between the groups (P > .05). PPD and CAL slightly improved for both groups with comparable mean values at 3 months. Evaluation of patient tolerance showed statistically significantly better values among patients receiving the test treatment (mean VAS [0-10], 1.51) compared to SRP (mean VAS [0-10], 3.66; P = .0012). The treatment of test sites was set to 5 seconds per site. The treatment of control sites, on the other hand, lasted 85 seconds on average. CONCLUSION The new erythritol powder applied with an air-polishing device can be considered a promising modality for repeated instrumentation of residual pockets during SPT. CLINICAL RELEVANCE With regard to clinical outcomes during SPT, similar results can be expected irrespective of the two treatment approaches of hand instrumentation or subgingival application of erythritol powder with an air-polishing device in sites where only biofilm removal is required.

A paradigm shift in mechanical biofilm management? Subgingival air polishing: a new way to improve mechanical biofilm management in the dental practice

In the past few years indications for the use of the air polishing technology have been expanded from supragingival use (airflow) to subgingival air polishing (perioflow) by the development of new low-abrasive glycine-based powders and devices with a subgingival nozzle. Several studies on the subgingival use of air polishing have been completed. On 7 June 2012, during the Europerio 7 Congress in Vienna, a consensus conference on mechanical biofilm management took place aiming to review the current evidence from the literature on the clinical relevance of the subgingival use of air polishing and to make practical recommendations for the clinician. Bernita Bush (Bern), Prof Johannes Einwag (Stuttgart), Prof Thomas Flemmig (Seattle), Carmen Lanoway (Munich), Prof Ursula Platzer (Hamburg), Prof Petra Schmage (Hamburg), Brigitte Schoeneich (Zurich), Prof Anton Sculean (Bern), Dr Clemens Walter (Basel), and Prof Jan Wennström (Gothenburg) discussed under the moderation of Klaus-Dieter Bastendorf and Christian Becker (both ADIC Association for Dental Infection Control) the available clinical studies to reach a consensus on available clinical evidence. This paper summarizes the main conclusions of the consensus conference and points to the clinical relevance of the findings for the dental practitioner.

Gingival fluid cytokine expression and subgingival bacterial counts during pregnancy and postpartum: a case series

OBJECTIVES The aim of this study was to assess gingival fluid (GCF) cytokine messenger RNA (mRNA) levels, subgingival bacteria, and clinical periodontal conditions during a normal pregnancy to postpartum. MATERIALS AND METHODS Subgingival bacterial samples were analyzed with the checkerboard DNA-DNA hybridization method. GCF samples were assessed with real-time PCR including five proinflammatory cytokines and secretory leukocyte protease inhibitor. RESULTS Nineteen pregnant women with a mean age of 32 years (S.D. ± 4 years, range 26-42) participated in the study. Full-mouth bleeding scores (BOP) decreased from an average of 41.2% (S.D. ± 18.6%) at the 12th week of pregnancy to 26.6% (S.D. ± 14.4%) at the 4-6 weeks postpartum (p < 0.001). Between week 12 and 4-6 weeks postpartum, the mean probing pocket depth changed from 2.4 mm (S.D. ± 0.4) to 2.3 mm (S.D. ± 0.3) (p = 0.34). Higher counts of Eubacterium saburreum, Parvimonas micra, Selenomonas noxia, and Staphylococcus aureus were found at week 12 of pregnancy than at the 4-6 weeks postpartum examinations (p < 0.001). During and after pregnancy, statistically significant correlations between BOP scores and bacterial counts were observed. BOP scores and GCF levels of selected cytokines were not related to each other and no differences in GCF levels of the cytokines were observed between samples from the 12th week of pregnancy to 4-6 weeks postpartum. Decreasing postpartum counts of Porphyromonas endodontalis and Pseudomonas aeruginosa were associated with decreasing levels of Il-8 and Il-1β. CONCLUSIONS BOP decreased after pregnancy without any active periodontal therapy. Associations between bacterial counts and cytokine levels varied greatly in pregnant women with gingivitis and a normal pregnancy outcome. Postpartum associations between GCF cytokines and bacterial counts were more consistent. CLINICAL RELEVANCE Combined assessments of gingival fluid cytokines and subgingival bacteria may provide important information on host response.

Subgingival microflora in inflammatory bowel disease patients with untreated periodontitis

OBJECTIVE To analyze the subgingival microflora composition of inflammatory bowel disease (IBD) patients with untreated chronic periodontitis and compare them with systemically healthy controls also having untreated chronic periodontitis. METHOD Thirty IBD patients [15 with Crohn's disease (CD) and 15 with ulcerative colitis (UC)] and 15 control individuals participated in the study. All patients had been diagnosed with untreated chronic periodontitis. From every patient, subgingival plaque was collected from four gingivitis and four periodontitis sites with paper points. Samples from the same category (gingivitis or periodontitis) in each patient were pooled together and stored at -70 °C until analysis using a checkerboard DNA-DNA hybridization technique for 74 bacterial species. RESULTS Multiple-comparison analysis showed that the groups differed in bacterial counts for Bacteroides ureolyticus, Campylobacter gracilis, Parvimonas micra, Prevotella melaninogenica, Peptostreptococcus anaerobius, Staphylococcus aureus, Streptococcus anginosus, Streptococcus intermedius, Streptococcus mitis, Streptococcus mutans, and Treponema denticola (P<0.001). CD patients had significantly higher levels of these bacteria than UC patients either in gingivitis or in periodontitis sites (P<0.05). CD patients harbored higher levels of P. melaninogenica, S. aureus, S. anginosus, and S. mutans compared with controls both at gingivitis and at periodontitis sites (P<0.05). UC patients harbored higher levels of S. aureus (P=0.01) and P. anaerobius (P=0.05) than controls only in gingivitis sites. CONCLUSION Our study showed that even with similar clinical periodontal parameters, IBD patients harbor higher levels of bacteria that are related to opportunistic infections in inflamed subgingival sites that might be harmful for the crucial microbe-host interaction.

Subgingival Aggregatibacter actinomycetemcomitans associates with the risk of coronary artery disease

AIM We investigated the association between angiographically verified coronary artery disease (CAD) and subgingival Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola. MATERIALS AND METHODS The cross-sectional study population (n = 445) comprised 171 (38.4%) patients with Stable CAD, 158 (35.5%) with acute coronary syndrome (ACS) and 116 (26.1%) with no significant CAD (No CAD). All patients participated in clinical and radiological oral health examinations. Pooled subgingival bacterial samples were analysed by checkerboard DNA-DNA hybridization assays. RESULTS In all study groups, the presence of P. gingivalis, T. forsythia and T. denticola indicated a significant (p ≤ 0.001) linear association with the extent of alveolar bone loss (ABL), but A. actinomycetemcomitans did not (p = 0.074). With a threshold level of bacterial cells 1 × 10(5) A. actinomycetemcomitans was significantly more prevalent in the Stable CAD group (42.1%) compared to the No CAD group (30.2%) (p = 0.040). In a multi-adjusted logistic regression analysis using this threshold, A. actinomycetemcomitans positivity associated with Stable CAD (OR 1.83, 95% CI 1.00-3.35, p = 0.049), but its level or levels of other bacteria did not. CONCLUSIONS The presence of subgingival A. actinomycetemcomitans associates with an almost twofold risk of Stable CAD independently of alveolar bone loss.

Subgingival microbiota of Sri Lankan tea labourers naïve to oral hygiene measures.

AIM To characterize the subgingival microbiota within a cohort of adult males (n = 32) naïve to oral hygiene practices, and to compare the composition of bacterial taxa present in periodontal sites with various probing depths. MATERIAL AND METHODS Subgingival plaque samples were collected from single shallow pocket [pocket probing depth (PPD)≤3 mm] and deep pocket (PPD≥6 mm) sites from each subject. A polymerase chain reaction based strategy was used to construct a clone library of 16S ribosomal RNA (rRNA) genes for each site. The sequences of ca. 30-60 plasmid clones were determined for each site to identify resident taxa. Microbial composition was compared using a variety of statistical and bioinformatics approaches. RESULTS A total of 1887 cloned 16S rRNA gene sequences were analysed, which were assigned to 318 operational taxonomic units (98% identity cut-off). The subgingival microbiota was dominated by Firmicutes (69.8%), Proteobacteria (16.3%), and Fusobacteria (8.0%). The overall composition of microbial communities in shallow sites was significantly different from those within deep sites (∫-Libshuff, p < 0.001). CONCLUSIONS A taxonomically diverse subgingival microbiota was present within this cohort; however, the structures of the microbial communities present in the respective subjects exhibited limited variation. Deep and shallow sites contained notably different microbial compositions, but this was not correlated with the rate of periodontal progression.