Application of substrate utilization patterns and terminal restriction fragment length polymorphism analysis to characterize the oral bacterial community of healthy subjects and patients with periodontitis.

Understanding the association between the bacterial community and oral health status is essential for the diagnosis and therapy of periodontal diseases. The aim of the present study was to apply three methods [conventional culture, substrate utilization using the MicroResp™ system and terminal restriction fragment length polymorphism (T-RFLP)] to investigate the oral bacterial community in saliva from 20 healthy subjects and 20 patients with periodontitis. The three methods all revealed that there was a systematic change in the microbial ecological characteristics associated with oral health status. Compared with the control group, the oral bacterial flora in the patients with chronic periodontitis had a greater culturable population and altered preferred carbon source and TRFLP patterns. TRFLP analysis was found to give more information and exhibit a higher sensitivity than the substrate utilization and conventional culture methods. In conclusion, TRFLP analysis is a potentially rapid method to assess the composition of the oral microbial community and for the diagnosis of chronic periodontitis.