Association of three bacterial species and periodontal status in Chinese adults: an epidemiological approach.

Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, and Tannerella forsythia are oral pathogens associated with periodontitis. The association between these three bacteria and periodontal disease has been reported in populations of many countries. However, corresponding data in Chinese populations are still lacking. The aim of this study was to detect these pathogens in subgingival plaque collected from 468 subjects with chronic periodontitis in a group of Chinese adults by using a PCR method and to determine the degree of association between the target bacteria and periodontal status based on logistic regression analysis. A. actinomycetemcomitans, P. gingivalis, and T. forsythia were found in 20.5%, 70.7%, and 77.1% of the subjects, respectively. About one-third (36.1%) of subjects had chronic periodontitis. Upon univariate analysis, age, male gender, current smoking status, diabetes, and the presence of A. actinomycetemcomitans or P. gingivalis were positively associated with chronic periodontitis, whereas education and income exhibited inverse associations with chronic periodontitis. Upon multivariate analysis, education, current smoking status, diabetes, and the presence of A. actinomycetemcomitans and P. gingivalis remained significant. The adjusted odds ratios for having chronic periodontitis were 2.5 and 3.4 in subjects positive for A. actinomycetemcomitans and P. gingivalis, respectively. However, no significant association was observed between the presence of T. forsythia and periodontal status. This study assesses the prevalence of periodontal pathogens and chronic periodontitis and the associations with sociodemographic characteristics among this group of Chinese adults. These findings also suggest that PCR should be considered for field oral epidemiologic studies and may be necessary in investigations presenting major logistic challenges.