Relationship between salivary blood group antigens, microbial flora and periodontal condition in young adults.

To investigate a possible rôle for salivary blood-group antigens in the relative frequencies of selected periodontal pathogens and commensal oral micro-organisms, we studied the clinical and microbiological condition in young adults with or without blood group reactive substances in saliva (secretors or non-secretors respectively). Clinical measurements were recorded at the Ramfjord teeth in 81 1st-year dental students. In addition, presence of interproximal loss of attachment (LA) was assessed at sites with a pocket depth of > or = 4 mm. Microbiological samples were taken from one of the Ramfjord teeth (site without interproximal LA), from interproximal sites of > or = 4 mm in conjunction with LA, and from the saliva. The samples were analyzed for the presence of Actinomyces naeslundii, Actinomyces viscosus, Campylobacter rectus, Fusobacterium nucleatum, Peptostreptococcus micros, Prevotella intermedia, Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans. Clinically, no statistically significant differences were found in the periodontal status between secretors (78% of our population) and non-secretors. Furthermore, the occurrence of the monitored micro-organisms was not correlated to the secretor status. It is concluded that bacterial colonization with the micro-organisms tested in this study, apparently occurred independent of secretor status. Among the periodontal pathogens, only P. intermedia was more frequently recovered from the saliva of subjects with interproximal LA (49%) than in those without (33%; p = 0.03). This finding was irrespective of the secretor status. Therefore, P. intermedia may be an important micro-organism in relation to the onset of periodontal destruction in young adults.