ACTINOBACILLUS-ACTINOMYCETEMCOMITANS GENOTYPES IN RELATION TO SEROTYPES AND PERIODONTAL STATUS

Actinobacillus actinomycetemcomitans is prevalent in periodontitis but is found in some periodontally healthy individuals as well. The arbit rarily primed polymerase chain reaction (AP-PCR) was used to fingerpri nt clinical A. actinomycetemcomitans isolates of different serotypes t o determine the association between individual clonal types and period ontal conditions. Fifteen different AP-PCR genotypes were distinguishe d among 93 A. actinomycetemcomitans isolates from 86 uncohabiting indi viduals with adult periodontitis, localized juvenile periodontitis or no periodontal destruction. The 3 most common AP-PCR genotypes account ed for 68% of the isolates. Seven of the remaining AP-PCR genotypes we re found only in periodontitis. The isolates of a given AP-PCR genotyp e usually belonged to the same serotype. The distribution of the AP-PC R genotypes among serotype b isolates seemed to differ among the subje ct groups. The results revealed a major genetic dissimilarity between A. actinomycetemcomitans serotypes and suggested a relationship betwee n some A. actinomycetemcomitans clones and periodontal disease.