Streptococcus mutans in children using nursing bottles.
This study aimed at comparing S.mutans in pairs of children within families; both children used a sweetened nursing bottle beyond the dietary need, while one child was affected with nursing bottle caries (NBC), the other not. Seven families were selected. The children of a pair showed no dissimilarities as regards dietary habits. Mean patient-age was 3.7 yrs, controls 5.7 yrs. Saliva and plaque were sampled for CFU-counting and clonal (DNA) type-screening of S.mutans. The NBC-patients harbored significantly more S.mutans than the controls (mean 5.8 CFU/ml vs. 2.9 CFU/ml). While the controls were colonized with 2-5 clonal types of S.mutans, in the patients only one type was observed. The results were not consistent for NBC-risk assessment by CFU-counting. An inverse relationship between the number of clonal S.mutans types and NBC is suggested.