[A study on distribution of Porphyromonas gingivalis in oral cavity by using a non-radioactive DNA probe method]

The purpose of this study was to evaluate the distribution of Porphyromonas gingivalis (P. gingivalis) in the dentition using a non-radioactive DNA probe and to compare the presence of P. gingivalis with the clinical parameters. Fifteen adult periodontitis patients and 6 clinically healthy volunteers were examined. Subgingival plaque samples were taken from 4 sites of all the remaining teeth. Probing depth and bleeding on probing (BOP) were also recorded. Plaque samples were investigated using a whole genomic DNA probe from P. gingivalis modified with bisulfite. In the patient group, the detection percentage and the amounts of P. gingivalis present were statistically compared with probing depth and BOP. As a result, P. gingivalis was detected in all 15 patients and 3 out of 6 healthy individuals. The detection average was 31% in the patient group. When the probing depth was over 4mm, 6mm or the BOP was positive, the detection percentage of P. gingivalis significantly increased in the patient group. As more P. gingivalis was identified, the percentage of the sites with deep probing depth or that were BOP-positive increased. However, P. gingivalis was also detected in the clinically healthy sites, and also it was not detected in some sites with deep probing depth or that were BOP-positive. These results indicate that P. gingivalis plays an important role, but is not the only microorganism responsible for adult periodontitis.