Periodontal pathogen carriage, rather than periodontitis, determines the serum antibody levels.

AIM: We investigated in a nationally representative sample, how periodontitis modifies the association between the carriage of periodontal pathogens and serology.
MATERIALS AND METHODS: The population comprised 1586 dentate subjects who participated in an interview, clinical and radiological oral health examination, and saliva collection. Serum immunoglobulin A (IgA)- and IgG-class antibody levels against Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis and their salivary occurrence were determined in the whole population. The quantity of the pathogens was measured in a subpopulation.
RESULTS: In the univariate analyses, the corresponding antibody levels were higher in the pathogen carriers compared with the non-carriers, and clearly higher in the carriers with periodontal pockets compared with the carriers without. In the multi-variate analyses, however, all antibody levels associated strongly with age (p<0.001) and the carriage of the corresponding pathogen (p<0.001), but only weakly with the presence or number of teeth with periodontal pockets. In the subpopulation, the antibody levels and the numbers of corresponding bacteria in saliva had a positive association, which was not affected by the disease.
CONCLUSIONS: The carriage of A. actinomycetemcomitans and P. gingivalis is the strongest determinant of the systemic antibody response to these pathogens, and the extent of periodontitis has at most a modest modifying effect.