Figure 3. Phylogenetic diversity of salivary bacterial populations of the individuals for various general and clinical conditions.

Of 2,343 individuals whose salivary bacterial composition was determined, 5 are excluded because of antibiotics use. Furthermore, 256 individuals with ≤8 teeth and 2 individuals from whom periodontal data were missing are excluded in %DFT, mean PPD, %teeth with BOP and mean plaque index. Dots indicate the mean; the error bars indicate 95% confidence intervals. ***P < 0.001, **P < 0.01, *P < 0.05 in bivariate analyses using Pearson’s correlation test^a or the Student’s t-test^b. The individuals are categorized into two groups by the Student’s t-test in terms of the number of DT and smoking history (presence vs. absence and current smokers vs. the other individuals, respectively). Abbreviation: BMI, body mass index; DT, decayed teeth; DFT, decayed and filled teeth, PPD, periodontal pocket depth; BOP, bleeding on probing.