Abstract
The distribution of Porphyromonas endodontalis, Porphyromonas gingivalis, Prevotella denticola, Prevotella intermedia, Prevotella loescheii, and Prevotella melaninogenica in periodontally healthy and diseased sites of patients was investigated. The periodontal pockets of two moderate periodontitis patients were scored clinically and sampled microbiologically at their first visit to Okayama University Dental Hospital. A total of 427 isolates of black-pigmented, anaerobic gram-negative rods (BPARs) were identified using a quick method of DNA-DNA hybridisation. In both subjects, all six BPAR species examined were distributed in clusters in certain areas of the dentition. P. gingivalis and Pr. intermedia were the most prevalent species identified. The DNA fingerprinting analysis of P. gingivalis isolates demonstrated that such a cluster 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 dentition. For one subject, clinical and microbiological examinations were performed again 3 months later. P. gingivalis and Pr. intermedia were still prevalent and distributed in clusters. Among the five preexisting 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 individual sites may explain the uneven progression of disease in the dentition.