ASSOCIATIONS BETWEEN 6 DNA PROBE-DETECTED PERIODONTAL BACTERIA AND ALVEOLAR BONE LOSS AND OTHER CLINICAL SIGNS OF PERIODONTITIS

The purpose of the present study was to assess the associations between the presence and amounts of Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, B. intermedius, Eikenella corrodens, Wolinella recta, and Fusobacterium nucleatum in the periodontal pocket and the degree of alveolar bone loss and other clinical signs of periodontitis, such as probing pocket depth, attachment level, and presence of bleeding on probing at the same site. The study material comprised 16 subjects with or without approximal sites showing longitudinal alveolar bone loss who were selected from a group of 142 subjects monitored radiographically over the past 4 years. In this group 105 sites were examined, of which 58 showed recent alveolar bone loss-greater-than-or-equal-to-1 mm. Subgingival plaque was collected with absorbent paper points and hybridized with P-32-labeled DNA probes specific for the above-mentioned bacteria. The amount of each bacterial species was correlated with the degree of bone loss over time and the three clinical measurements by means of Spearman rank correlation. A. actinomycetemcomitans showed poor correlations with all three clinical signs of periodontal inflammation, whereas B. gingivalis and W. recta demonstrated significant positive correlations with the three clinical measurements and with attachment level and pocket depth, respectively. In addition, the amount of A. actinomycetemcomitans, B. gingivalis and W. recta showed significant positive correlation with the extent of alveolar bone loss at the site. In contrast, the amounts of B. intermedius, E. corrodens, and F. nucleatum showed negative correlations with all four measurements. B. gingivalis and W. recta demonstrated stronger associations when their amounts in the pocket were combined and when proportions relative to the amount of B. intermedius, E. corrodens, and F. nucleatum at the site were assessed. Thus, the results support the concept that specific combinations and relations of organisms rather than single organisms may play an important role in the pathogenesis of periodontitis.