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 arbitrarily primed polymerase chain reaction (AP-PCR) was used to fingerprint clinical A. actinomycetemcomitans isolates of different serotypes to determine the association between individual clonal types and periodontal conditions. Fifteen different AP-PCR genotypes were distinguished among 93 A. actinomycetemcomitans isolates from 86 uncohabiting individuals with adult periodontitis, localized juvenile periodontitis or no periodontal destruction. The 3 most common AP-PCR genotypes accounted for 68% of the isolates. Seven of the remaining AP-PCR genotypes were found only in periodontitis. The isolates of a given AP-PCR genotype usually belonged to the same serotype. The distribution of the AP-PCR genotypes among serotype b isolates seemed to differ among the subject groups. The results revealed a major genetic dissimilarity between A. actinomycetemcomitans serotypes and suggested a relationship between some A. actinomycetemcomitans clones and periodontal disease.