Etiology of nursing caries: A microbiologic perspective

A compelling body of scientific evidence supports the concept that nursing caries is an infectious and transmissible disease. This evidence makes a strong case to support the tenet that infants who are colonized by mutans streptococci, and who have feeding habits characterized by frequent and prolonged oral exposure to cariogenic substrates, are likely to have a drastic increase in their oral mutans streptococci populations. Such an increase is associated with a high risk for rampant dental caries. This evidence strongly suggests that the first step in the etiology of nursing caries is primary infection by mutans streptococci; the second step is accumulation of these organisms to pathogenic levels as a consequence of frequent and prolonged oral exposure to cariogenic substrates; and the third step is rapid demineralization and cavitation of enamel resulting in rampant dental caries. This three-step model might provide an important framework for the design of clinical trials targeted at prevention of nursing caries.