Salivary microbial levels in relation to periodontal status and caries development

Iwano Y, Sugano N, Matsumoto K, Nishihara R, Iizuka T, Yoshinuma N, Ito K. Salivary microbial levels in relation to periodontal status and caries development. J Periodont Res 2010; 45: 165–169. © 2010 John Wiley & Sons A/S Background and Objective: Although an inverse relationship between caries and periodontal disease has been suggested, some studies have reported a positive correlation between periodontal disease and the decayed, missing and filled teeth (DMF) index. The aim of the present study was to examine the relationship between caries and periodontal disease. Material and Methods: We assessed the clinical parameters and salivary levels of Porphyromonas gingivalis and Streptococcus mutans using real-time polymerase chain reaction in 40 subjects with varying degrees of caries and periodontal disease. Results: The salivary levels of S. mutans were significantly higher in the periodontally healthy group than in the periodontitis group. The salivary levels of P. gingivalis were significantly higher in the caries-free group than in the periodontally healthy group with caries. The salivary levels of S. mutans were significantly increased after the initial periodontal treatment. Conclusions: This study showed that an inverse relationship exists between periodontitis and caries in terms of the clinical and bacteriological findings.