SUBGINGIVAL TEMPERATURE .3. RELATION TO MICROBIAL COUNTS

The present investigation examined the relationship of selected bacterial species and subgingival temperature. 35 subjects were measured at 6 sites per tooth for clinical parameters and subgingival temperature. Measurements were repeated for 21 subjects at 2 month intervals providing a total of 66 subjects visits. At each visit, subgingival plaque samples were taken from the mesial aspect of each tooth and anaerobically dispersed, diluted and plated on non-selective media. After anaerobic incubation, colonies were lifted to nylon filters and specific species detected using digoxigenin-labeled whole chromosomal DNA probes. Species enumerated were; A. actinomycetemcomitans serotypes a and b, B. forsythus, B. gingivalis, B. intermedius I and II, C. ochracea, F. nucleatum ss. vincentii, P. micros, S. intermedius, S. sanguis I and II, V. parvula and W. recta. Total viable counts and counts of Capnocytophaga sp. were determined directly from the primary isolation plates. A total of 1581 samples were evaluated. Subject visits with higher mean subgingival temperatures had significantly higher mean %s of B. intermedius I and P. micros, and lower mean %s of Capnocytophaga sp. Sites with higher subgingival temperatures had elevated proportions of B. intermedius I and II, A. actinomycetemcomitans serotype a and B. gingivalis more frequently than sites with lower temperatures, while Capnocytophaga sp. were elevated more often at cooler sites. 43 of the subject visits had follow up attachment level measurements at 2 months. The 1026 microbial samples and the subgingival temperature measurements from these visits were related to longitudinal attachment change. Discriminant analysis indicated that combinations of temperature and microbial parameters were more effective in predicting subjects at risk and sites at risk for new attachment loss than either group of variables alone.