EVALUATION OF ORAL BACTERIA AS RISK INDICATORS FOR PERIODONTITIS IN OLDER ADULTS

THE PREVALENCE OF PEOPLE AND SITES WITH ATTACHMENT LOSS, pocket depth, Actinobacillus actinomycetemcomitans, Prevotella intermedia, and Porphyromonas gingivalis are described for a random sample of 366 black and 297 white community-dwelling adults, aged 65 or over, residing in five counties in North Carolina. In addition, relationships between sites harboring these microorganisms and loss of attachment (LA) and pocket depth (PD) are presented in a manner that considers the lack of independence of sites within each person. Pocket depths and recession were measured on all teeth by trained examiners during household visits. Immunofluorescent assays for A. actinomycetemcomitans, P. intermedia, and P. gingivalis were conducted on subgingival plaque samples obtained from the mesiobuccal aspect of the four first molar teeth using paper points. The prevalences of A. actinomycetemcomitans, P. intermedia, and P. gingivalis were greater in blacks than in whites. The most striking difference was seen for P. gingivalis, which was found in 38.8% of blacks and 9.4% of whites. Similar relationships were found when the percent of sites with these organisms were assessed. Blacks with P. gingivalis or P. intermedia had a higher prevalence of sites with LA greater-than-or-equal-to 7 mm as compared to blacks not infected with P. gingivalis or P. intermedia. The same was true for whites. Similar relationships between P. gingivalis or P. intermedia and PD greater-than-or-equal-to 6 mm were found for both blacks and whites. However, the greater prevalence for blacks than whites for LA greater-than-or-equal-to 7 mm or PD greater-than-or-equal-to 6 mm when both were infected with P. gingivalis or P. intermedia were suggestive trends rather than significant. Finally, a logistic regression model for LA greater-than-or-equal-to 7 mm showed that race was no longer a significant explanatory variable when P. gingivalis, P. intermedia, last visit to the dentist being more than 3 years ago, and tobacco use were already in the model. It is clear that destructive periodontal disease is the result of a complex relationship among subgingival microflora and non-bacterial factors. The interaction between the microbial flora and these other factors present a fruitful area of investigation in order to fully understand the complexity of periodontal disease in adults.