DISTRIBUTION OF BLACK-PIGMENTED PREVOTELLA AND PORPHYROMONAS SPECIES IN THE DENTITION OF MODERATE PERIODONTITIS PATIENTS

The distribution of Porphyromonas endodontalis, Porphyromonas gingival is, Prevotella denticola, Prevotella intermedia, Prevotella loescheii, and Prevotella melaninogenica in periodontally healthy and diseased s ites of patients was investigated. The periodontal pockets of two mode rate periodontitis patients were scored clinically and sampled microbi ologically at their first visit to Okayama University Dental Hospital. A total of 427 isolates of black-pigmented, anaerobic gram-negative r ods (BPARs) were identified using a quick method of DNA-DNA hybridisat ion. In both subjects, all six BPAR species examined were distributed in clusters in certain areas of the dentition. P. gingivalis and Pr. i ntermedia were the most prevalent species identified. The DNA fingerpr inting analysis of P. gingivalis isolates demonstrated that such a clu ster was composed of one or two clonal types of the same species, and that five clonal types of the species were present in the whole dentit ion. For one subject, clinical and microbiological examinations were p erformed again 3 months later. P. gingivalis and PI. inter-media were still prevalent and distributed in clusters. Among the five preexistin g clonal types of P. gingivalis, four were still found, and six other types were recognised. Site-to-site and time-to-time variations in the species profile of BPAR and the clonal profile of P. gingivalis in in dividual sites may explain the uneven progression of disease in the de ntition.