Methods: Twenty six subjects presenting aggressive periodontitis, aged 19 to 35 and three healthy negative controls were evaluated for sera antibodies to A.actinomycetemcomitans serotypes a, b and c by ELISA. Sera were considered responsive to each serotype when the OD corrected values > mean OD healthy + 7sd.
Results: Data revealed that IgG levels were positive for A.actinomycetemcomitans in 6 of 12 afro descendant patients. Five of these positive patients had high antibodies titers to serotype b, including 3 responsive also to serotypes a and /or c. However, an immune response to A.actinomycetemcomitans was observed in 12 of 14 Caucasian subjects. Ten of these subjects were immune responsive to serotype b, including 4 sera responding also to serotypes a and/or c.
Conclusion: response to A.actinomycetemcomitans serotype b was shown to be strongly associated with generalized aggressive periodontitis, especially among Caucasian aggressive periodontitis patients.