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. 40 subgingival taxa were quantified using checkerboard DNA-DNA hybridization and the concentrations of 8 GCF cytokines 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-1β (IL-1β) (p<0.001), granulocyte-macrophage colony-stimulating factor (GM-CSF) (p<0.01), and IL-1β/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-1β/ 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-1β/ IL-10 ratio than periodontally healthy subjects, suggesting an imbalance between pro-and antiinflammatory cytokines in aggressive periodontitis. KeywordsGeneralized aggressive periodontitis; microbiota; gingival crevicular fluid; biomarkers Clinical RelevanceScientific rationale for study: Periodontal diseases result from interactions between specific subgingival microbial species and the susceptible host. However, very little is known regarding the impact of the subgingival biofilm composition on the secretion of biomarkers by the adjacent periodontal tissues.

2, 3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide (XTT) reduction assay has been used to study Candida biofilm formation. However, considering that the XTT reduction assay is dependent on cell activity, its use for evaluating mature biofilms may lead to inaccuracies since biofilm bottom cell layers tend to be relatively quiescent at later stages of biofilm formation. The aim of this study was to improve XTT reduction assay by adding glucose supplements to the standard XTT formulation. Candida albicans ATCC 90028 was used to form 24-, 48- and 72-h biofilms. The oxidative activity at 90, 180 and 270 min of incubation was evaluated. The control consisted of standard XTT formulation without glucose supplements, and was modified by the addition of 50, 100 and 200 mM of glucose. The XTT assay with 200 mM glucose showed more accurate and consistent readings correlating with biofilm development at 24, 48 and 72 h. Biofilm growth yield after 180 min incubation, when evaluated with the 200 mM glucose supplemented XTT, produced the most consistent readings on repetitive testing. It may be concluded that glucose supplementation of XTT could minimize variation and produce more accurate data for the XTT assay.

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The borderline association of the study polymorphism with implant loss suggests further IL1 haplotype analysis to elucidate the global involvement of IL-1 proteins in the modulation of the osseointegration process.

While there was a high prevalence of temporomandibular disorders in the professional athletes in our study, the prevalence of the condition in recreational athletes was similar to that in individuals who did not practice martial arts.

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This in vitro study showed that the amount of sodium ascorbate required for reduction of hydrogen peroxide is directly related to the concentration of the latter. In addition, the reaction kinetics between oxidant and antioxidant showed that a longer application time for sodium ascorbate does not influence the effectiveness of the reaction and that 5 min is sufficiently long for this antioxidant to exert an antioxidant effect.

The present study evaluated the relationship between clonal diversity and some virulence traits of Streptococcus mutans isolated from eight caries-free and eight caries-active subjects. A total of 155 S. mutans isolates from caries-free subjects and 144 isolates from caries-active subjects were obtained from samples of saliva, dental plaque and tongue surface and identified by PCR. The isolates were submitted to arbitrarily primed (AP)-PCR (OPA-2 and OPA-13) and multilocus enzyme electrophoresis (MLEE) to establish the genotypic diversity. Production of water-insoluble glucan (WIG) (monitored by SDS-PAGE), final pH of cultures and the ability of bacterial cells to adhere to smooth glass in the presence of sucrose were measured. High and comparable abilities of MLEE and AP-PCR were found to distinguish S. mutans genotypes, using Simpson's index of discrimination (0 . 971 and 0 . 968, respectively). The results showed a significant difference (P , 0 . 01) in the number of genotypes when caries-free and caries-active groups were compared by both fingerprinting methods used. Final pH (P ¼ 0 . 32) and the percentage of adherence to a glass surface (P ¼ 0 . 62) did not show differences between the two groups; however, the intensities of WIG bands from the caries-active group were greater than those from the caries-free group (P , 0 . 01). In addition, WIG was positively correlated with the ability of S. mutans to adhere to a glass surface (r ¼ 0 . 34, P ¼ 0 . 02) from caries-active subjects. These data showed that AP-PCR analysis and MLEE are both effective methods for assessing the genetic relatedness of S. mutans. Using these techniques, it was found that there is a larger number of genotypes of S. mutans with increased ability to synthesize WIG in caries-active individuals.