PREVALENCE OF TREPONEMA-DENTICOLA AND PORPHYROMONAS-GINGIVALIS IN PLAQUE FROM PERIODONTALLY-HEALTHY AND PERIODONTALLY-DISEASED SITES

Intracrevicular plaque from periodontally-healthy individuals who had refrained from oral hygiene measures for 24 h prior to sampling, and s ubgingival plaque from diseased sites of patients with chronic periodo ntitis were screened by ELISA for the presence of Porphyromonas gingiv alis and Treponema denticola. The samples were also subjected to the P erioScan test to detect the presence of enzymes capable of degrading N -benzoyl-DL-arginine-2-naphthylamide (BANA). Of the 141 samples from p eriodontally-healthy sites, 73 % contained T. denticola antigens and 7 8 % P. gingivalis antigens, compared to 43 % and 59 %, respectively, i n plaque samples from the 159 diseased sites. A positive reaction in t he PerioScan test was obtained in 89 % of plaque samples from diseased sites and in 60 % of those from healthy sites. The correlation betwee n the results of the two assays was poor in the case of intracrevicula r plaque from healthy sites. However, with plaque samples from disease d sites, the results of the PerioScan test showed very strong correlat ion with those obtained with the ELISA, suggesting that the former may be a useful, rapid means of indicating the presence of T. denticola a nd P. gingivalis in such plaque samples.