Human serum precipitins to oral bacteria related to dental caries

Adults aged 20-38 years were classified by a positive (+) or negative (-) precipitating serum antibody response to D-alanyl glycerol teichoic acid (S), or an antigen from Actinomyces spp. (A). Culture filtrates of Streptococcus mutans and Actinomyces viscosus were used to detect the respective specific antibodies by immunoelectrophoresis and immunodiffusion when present in serum at a concentration of more than 0.05 mg/ml. Among subjects who had grown up in fluoridated areas, A+ subjects exhibited significantly fewer decayed, missing and filled teeth or teeth surfaces compared to A- subjects (p less than 0.02). For the whole population examined, caries severity increased with age and decreased with length of residence in a fluoridated area (p less than 0.01). When classified by A and S antibody response, only S-subjects showed a significant increase in caries score with age (p less than 0.02) and only A+S+ subjects a significant decrease in score with length of exposure to fluoridated water (p less than 0.05). It is concluded that the severity of caries in relation to age and fluoride exposure may differ in subjects with the different antibody specificities.