Subgingival microbiological profile of obese and non-obese subjects with chronic periodontitis

Abstract

The obesity is currently considered a risk indicator for periodontal diseases. However, the biological mechanisms that could explain the higher incidence and severity of periodontal diseases in obese subjects remain unclear. In relation to the microbiological aspects, there is scarce evidence in the literature on the relationship between obesity and the subgingival microbiological profile. Therefore, the aim of this study will be to evaluate the subgingival microbiological profile of obese and non-obese subjects with chronic periodontitis, when compared to obese and non-obese individuals without periodontitis. Based on pre-established criteria, 160 subjects will be allocated into one of the following groups: obese subjects with chronic periodontitis (n=40), obese subjects without periodontitis (n=40), non-obese subjects with chronic periodontitis (n=40) and non-obese subjects without periodontitis (n=40). The subjects will be submitted to periodontal clinical examination and subgingival biofilm sampling. Six non-contiguous sites will be sampled per chronic periodontitis subject, 3 sites presenting clinical attachment level (CAL) and probing depth (PD) igual or lesser than 3mm without marginal bleeding (MB) and/or bleeding on probing (BoP) and 3 sites presenting CAL e PD igual or higher than 5 mm with BoP. Six sites with CAL and PD igual or lesser than 3mm without MB and/or BoP will be sampled per non-periodontitis subject. The biofilm samples will be analyzed for the levels and proportions of 40 bacteria species using the Checkerboard DNA-DNA hybridization technique. Based on data normality, the comparison among groups will be performed by ANOVA or Kruskal-Wallis test, using a significance level of 5%. Adjustments for multiple comparisons will be performed for the microbiological comparisons.