Identification of treponema denticola, porphyromonas gingivalis and their virulence factors in infected root canals by molecular microbiologic techniques

The aim of this study was to assess the presence and prevalence of T. denticola, P. gingivalis and their msp and prtC genes in the infected root canals by Real-time PCR. The relationship between the presence of these two endodontopathogens, their virulence genes and the clinical symptomatology was also evaluated. The infected pulps of 60 patients were divided into three clinical groups: acute apical periodontitis, chronic apical periodontitis, acute apical abscess. DNA was extracted from samples which were further analysed using the primers and probes that are specific for T. denticola and P.gingivalis. In the samples that yielded positive P.gingivalis DNA amplicon, in order to detect the collagenase gene Real-time PCR were performed using prtC specific bacterial primers and Taq Man probes. Conventional PCR method was employed to identify msp in the samples that were positive for T.denticola. T.denticola was found in 44.1% of the total samples, in 12 of 26 cases with acute apical periodontitis, one of seven cases with acute apical abscess, and 12 of 27 cases with chronic apical periodontitis. P.gingivalis was observed in 16.7% of the total, three of 26 cases with acute apical periodontitis, two of seven cases with acute apical abscess, and five of 27 cases with chronic apical periodontitis. msp DNA was detected in seven of 26 T.denticola positive samples, and prtC DNA was detected in nine of ten P.gingivalis positive samples. The association between the presence of the bacteria, the virulence genes and three clinical pathologies was not statistically significant (p>0.05). Key words: Collagenase, major surface protein, Porphyromonas gingivalis, Real-time PCR, Treponema denticola