The influence of family size on the prevalence of dental caries in children

Abstract

A comparative study of dental caries prevalence was made between 283 first-born children with no siblings and 830 children whose birth-rank order was third or later. These children comprised 149 “only” children and 500 of later birth rank in the age group 5–8 years, between whom comparison of caries experience of the deciduous teeth was made. For comparison of caries in the permanent teeth, 134 “only” children were compared with 280 children of later birth rank, with an approximate age of 13 years and who had erupted not less than twenty-five and not more than twenty-eight permanent teeth. The results show that the average number of decayed, missing and filled teeth per child is lower in those whose birth rank was “third or later”, compared with the “only” children. These findings are compared with those of two earlier studies in which the reverse relationship was found and the differences between this present study and the earlier studies are discussed. The literature cited provides evidence to show that size of family exerts a measurable influence upon family economics, diet and nutrition. The differences in caries between the birth-rank orders are thought to be related to the direct effect of diet upon the oral environment of the tooth. This suggests, therefore, that susceptibility to caries can respond in a sensitive manner to relatively small changes in the dietary. It is concluded that dietary differences due to social and economic conditions are sufficient to influence susceptibility to dental caries in school children.