Bacteriological Evaluation of Periodontal Pockets before and after Initial Preparation Using DNA Probe Technology

The purpose of this study was to evaluate the effects of initial preparation on three periodontal pathogens, A. actinomycetemcomitans (Aa), B. gingivalis (Bg) and B. intermedius (Bi), in periodontal pockets. Twelve adult cases of periodontitis (43 sites) involving a probing depth of over 5 mm were examined in this study. Microbiological and clinical changes after initial preparation were compared with those at the first examination. Microbiological examination was performed by assessing the bacteriological distribution of three periodontal pathogens in periodontal pockets using the DMDx® Test. Clinical examination included assessment of Plaque Index (P1I), Gingival Index (GI), Bleeding on probing Bop), suppuration (sup) and probing depth (pd). The results were as follows: Clinical parameters were improved after initial preparation, and the decrease in probing depth was especially remarkable. In microbiological examination, the frequency of detection of the three periodontal pathogens was decreased, being markedly so for Bg. The number of sites with changes indetection rates from a high level to a negative level was 14 sites in Bg, and improvement was seen in 3, and the decreased frequency of detection of Bg was seen too in classification by periodontal pathogenicity. It was shown that Bg responded well in comparison with Aa and Bi to initial preparation. A positive correlation was observed between detection of the three periodontal pathogens, i. e. Aa+Bg+Bi, and probing depth before and after initial preparation. The results of the present investigation suggest that DMDx® Test is a clinically useful method for assessing the three periodontal pathogens.