The relationship between dental caries in the primary dentition and anti S. mutans serum antibodies in children with Down's syndrome.

The purpose of this study was to evaluate the status of dental caries in seventy-five subjects with Down's Syndrome, ages two to eighteen years and to evaluate the relationship between dental plaque or caries experience and serum antibody titers against S. mutans and S. mitis. These antibodies were examined since an enhanced host response to S. mutans might be responsible for the low caries prevalence in Down's Syndrome. Antibody titers were determined using the enzyme-linked immunosorbant assay (ELISA) and titers were expressed in ELISA units. The frequency of all subjects who were caries-free was 46.1%, while 61.4% of the subjects under five years were caries-free. The average DMFT score in the subjects of Hellman Dental Age group I (primary dentition) was 15.9. The highest frequency of caries occurred on occlusal surfaces, followed by proximal surfaces of the upper incisors and smooth surfaces on incisors. The severity of dental caries in the subjects with Down's Syndrome was bipolar and could be categorized as either mild or severe. In the subjects having a primary dentition, a significant positive correlation was found in the relationship between the Original Caries Severity Score (OCSS) and the plaque score. There was also a significant positive correlation between OCSS and IgM antibody titer to S. mutans. In contrast, no correlation between antibody titers to S. mitis and these variables was found. It is not clear if these antibodies are protective and responsible for the reduced caries rate seen in Down's Syndrome.