[Distribution of fimA genotype of Porphyromonas gingivalis in Chinese periodontitis patients and its relationship with chronic periodontitis].

OBJECTIVE: To investigate the distribution of fimA genotype of Porphyromonas gingivalis in Chinese periodontitis patients and try to find the relationship between fimA genotype and chronic periodontitis. METHODS: Subgingival plaque samples were collected from 101 periodontitis patients. P. gingivalis 16S rRNA primer and fimA type-specific primer were designed. The distribution of fimA genotype in periodontitis patients was detected by PCR. Clinical periodontal indices (PPD, CAL and BOP) were measured at the sample tooth's six points; namely, the mesio-, mid-, distobuccal and mesio-, mid-, distolingual points. RESULTS: P. gingivalis was detected in 89 periodontitis patients (88.1%). Among them, a single fimA genotype was detected in most subgingival plaque samples (65.1%), and the most prevalent fimA genotype was type II (43.8%), followed by type IV (40.4%); Type II fimA and IV fimA were more frequently detected in mild/moderate periodontitis group and severe periodontitis group. CONCLUSION: The findings indicate that P. gingivalis with type II fimA and IV fimA are more predominant in Chinese periodontitis, and the organisms are involved in the destructive progression of periodontitis in Chinese.