Back ground: Pathogenic oral bacteria induces not only peridontitis and dental caries, but also contribute to causing systemic diseases. However, large-scale etiological study for characterizing regional distribution pattern of pathogenic bacteria is lacking.
Aim: To obtain data of distribution pattern of pathogenic bacteria in shimane prefecture.
Method: Saliva samples were collected from local residents of 7 area in shimane prefecture (1588 samples). Bacterial genome DNA was extracted. Then, following bacteria was detected by PCR; P.gingivalis (P.g), T.denticola (T.d), T. forsythia (T.f), P. intermedia (P.i), A. actinomycetemcomitans (A.a), S. mutans (S.m).
Results: Infection percentage of T.f and A.a was 90% and more in all area. In contrast, frequency of T.d inection was very low every area. There are regional differences in infection of P.g, P.i, S.m. Especially inland residents frequently had P.g compared to people in other area. One area showed outstanding low infection percentage in S.m. Number of people who had both P.g and S.m were almost same with number of S.m-infected people in each area.
Conclusion: Each area showed distinct infections pattern, suggesting that living environment affects the infection of oral pathogenic bacteria.