[Detection of gingipian gene of Porphyromonas gingivalis in subgingival plaque].

Purpose: The purpose of this study was to detect two genes (kgp-cd and rgpB-cd) of Porphyromonas gingivalis in subgingival plaque, and determine the relationship between the two genes and the periodontal clinical indexes.
Methods: Eighty four subgingival plaque samples were included in this study. The extracted DNA was amplified with the primers designed to obtain the genes encoding the catalytic domain of kgp and rgpB (kgp-cd, rgpB-cd), and typing P.gingivalis into two genotypes. The relationship between different genotypes of P. gingivalis and the periodontal clinical indexes was statistically analyzed by SPSS11.5 software package for Student's t test and Chi-square test.
Results: The detection rate of type-A P.gingivalis (85.29%) was higher than that of type-B P.gingivalis (14.71%), P<0.05. Both probe depth and bleeding on probing had significant difference between different genotypes of P.gingivalis (PD:t=2.85,P<0.05;BOP:P<0.05).
Conclusions: kgp-cd and rgpB-cd were related to pathogenicity of P.gingivalis.