Abstract: Objective:?To investigate the prevalence and distribution of total bacteria, Porphyromonas gingivalis (P. gingivalis), Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) and leukotoxin (LTX) in Jiangsu Han nationality periodontitits subjects categorized by classifications in 2018 and 1999. Methods:?73 patients with periodontitis and 26 periodontal healthy individuals were recruited. Periodontal clinical parameters were recorded, including probing depth (PD), clinical attachment loss (CAL), gingival index (GI) and plaque index (PLI). Levels of total bacteria, P. gingivalis and A. actinomycetemcomitans in subgingival plaque were explored by real-time PCR, and LTX was detected by conventional PCR. Results:?There were no differences in the levels of total bacteria and P. gingivalis between chronic and aggressive periodontitis (P>0.05), while differences were found when subjects were grouped by staging and grading (P＜0.05). Moreover, differences in the levels of A. actinomycetemcomitans and positive rates of LTX between chronic and aggressive periodontitis patients, between Stage Ⅰ-Ⅱ and Ⅲ-Ⅳ patients, and between Grade A and C patients were disclosed (P>0.05). All LTXs detected in this study were subtypes of low virulence. Positive correlations were confirmed between periodontal clinical parameters (PD, CAL and GI) and the levels of total bacteria, P. gingivalis and A. actinomycetemcomitans. (P＜0.05) Conclusions:?Classification for periodontal diseases in 2018 well reflected the microbiological characteristics of Jiangsu Han nationality periodontitis patients.

Key words: Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, leukotoxin, periodontitis, classifications