Objective: This study aimed to evaluate the frequency of A.actinomycetemcomitans serotype-specific antigens and its association with P.gingivalis, P.intermedia, T.forsythia and C.rectus in Brazilian subjects.
Method: A wide group of subjects (n=1320) had their periodontal status determined and were screened for the subgingival presence of A.actinomycetemcomitans serotypes. Then, a total of 263 individuals A.actinomycetemcomitans positive for serotypes a; b; c and e were considered in this survey. Subsequently, in this same group of positive subjects, the presence of P.gingivalis, P.intermedia, T.forsythia and C. rectus from periodontal pockets were also evaluated by PCR.
Result: Out of 263 subjects investigated, A.actinomycetemcomitans serotype a was detected in 28.5% subjects; serotype b in 15.97%; serotype c in 51.71% and serotype e in 3.80% subjects. The frequency of serotype a of A.actinomycetemcomitans was significantly higher in C.rectus positive subjects than in P. gingivali, P. intermedia or T. forsythia positive subjects. Additionally, the frequency of serotypes b and c were significantly higher in both C.rectus and T.forsythia positive subjects in comparison to P.gingivalis and P.intermedia positive subjects. Meanwhile, the frequency of serotype e was not associated with the presence of the other periodontal pathogens investigated.
Conclusion: Our study is in agreement with previous reports showing that the distribution of A.actinomycetemcomitans serotypes was influenced by the presence of other oral microorganisms. In particular, we observed a positive association between A.actinomycetemcomitans serotypes a, b and c with C.rectus and T.forsythia.