Response to Seow: biological mechanisms of early childhood caries.

For more than three decades, it has been recognized that dental caries is an infectious and transmissible disease in which diet plays a key role. Nevertheless, in treating patients with early childhood caries, scant attention is placed on exploring the source of infection and the prevalence of caries in other family members. Results from studies conducted in animals clearly show that the virulence of mutans streptococci can be enhanced by a highly cariogenic environment. For example, offspring from a highly caries-active dam develop significantly more caries than pups from a low caries-active dam. Considerable attention has been placed on the role of the nursing bottle in early childhood caries. Milk and some infant formulas do not promote caries and the role of the remainder of the diet has been largely ignored. The nursing bottle can effectively block salivary access to tooth surfaces, thereby increasing the cariogenicity of any food remaining in the mouth. Recent evidence shows that salivary gland function is impaired by iron deficiency and by prenatal exposure to lead. Clearly, early childhood caries is a complex disease that requires careful and extensive investigation.