Relationship of levels of the bacterium Streptococcus mutans in saliva of children and their parents

Abstract

85 Children diagnosed as caries free (CF), and 67 caries-positive (CP) children, aged 5–8 yr, were studied for the presence of Streptococcus mutans in saliva. All mothers and most fathers of 50 of the CF children and about 2 3 of the mothers of the CP children were studied similarly. The detection frequency of Strep. mutans in the CF children (59 per cent) was significantly lower than that in the CP children (96 per cent); its mean and median levels were also significantly lower (about 10-fold) in CF children. The detection frequency of Strep. mutans in the mothers of the CF children (62 per cent) was also significantly lower than that in either the fathers of these children (92 per cent) or the mothers of the CP children (100 per cent); this was so also for median salivary Strep. mutans levels. A tendency towards a positive association was found between the Strep. mutans levels of the CP children and their mothers but not between the CF children and either their mothers or fathers. The findings support a role of Strep. mutans in the aetiology of dental caries and suggest a familial tendency with respect to oral Strep. mutans infection.