There were specific microbial complexes in supragingival plaque that were similar to those found in subgingival plaque samples with a few minor differences. The relation of previously unclustered taxa to the complexes was also described.

The significant reduction of red and orange complex species at 2 weeks in the subjects receiving SRP plus azithromycin or metronidazole may have contributed to a better clinical response in these treatment groups. Therapy did not appear to create lasting changes in the percentage of resistant isolates or sites harboring resistant species.

Many putative periodontal pathogens associated with periodontal disease in human immunodeficiency virus (HIV)-infected patients also occur in non-HIV-infected individuals. This study examined the prevalence of eight periodontal pathogens in HIV-positive and HIV-negative patients with chronic periodontitis using the 16s RNA polymerase chain reaction technique. The results showed a significant prevalence of Porphyromonas gingivalis and Treponema denticola among HIV-negative patients compared to HIV-positive patients. Sixty percent of the patients in both groups were colonized by five to six species. Odds ratio analysis revealed a statistically significant positive association between three of the 28 possible combinations in the HIV-positive group. They included Prevotella nigrescens/Campylobacter rectus, P. nigrescens/P. gingivalis and P. nigrescens/T. denticola. Although the prevalence of periodontal pathogens is similar in both the groups, the combination of certain periodontal pathogens may be responsible for chronic periodontitis seen in HIV-infected adults.

Objective-To test the hypothesis that tooth location affected the microbial composition of supragingival plaque beyond the effect due to plaque mass as reflected by total DNA probe count.Methods-Supragingival plaque samples were taken from the mesiobuccal aspect of each tooth in 187 subjects at baseline (N samples = 4,745). All samples were individually analyzed for their content of 40 bacterial species using checkerboard DNA-DNA hybridization. Significance of differences in mean species counts and proportions were determined among tooth surfaces and 6 tooth type categories: molars, bicuspids, incisors/canines in the mandible and maxilla separately using the Kruskal Wallis test. Stepwise multiple linear regression was employed to examine the relationship between species proportions and total DNA probe count, tooth location, periodontal and smoking status, age and gender.Results-All species differed significantly among tooth types and among the 6 tooth categories. Higher plaque levels were seen at molars and lower incisors. Some differences observed between tooth types could be partially explained by the level of plaque. Teeth with high plaque mass exhibited high levels of Capnocytophaga gingivalis, Actinomyces naeslundii genospecies 2, Campylobacter rectus and Campylobacter showae. However, certain species such as Veillonella parvula and Streptococcus sanguinis differed significantly at different tooth locations despite similarities in plaque mass. Twenty of the test species exhibited a significant association with tooth location after adjusting for total DNA probe count and subject level factors.Conclusion-While plaque mass was associated with differences in proportions of many species in supragingival biofilms, tooth location also was strongly associated with species proportions in both univariate and multivariate analyses.

Treated periodontitis subjects under maintenance displayed more rapid attachment loss than periodontally healthy subjects in a preventive regimen. The greater propensity to disease progression may be related to an elevated exposure to periodontal pathogens.