Relationship of fluid transport through the dentin to the incidence of dental caries.

It is generally accepted that three conditions are essential in the oral cavity for dental caries to occur: a suitable microbe, a substrate for the microbe, and a susceptible tooth. Susceptibility or resistance to dental caries is usually thought of in terms of structure, which is determined, for the most part, during calcification. However, it is also plausible that susceptibility to dental caries may be related to altered metabolism within the tooth. To maintain a rapid rate of metabolism through the Embden-Meyerhof pathway in the avascular dentin, as reported by Bosia, Arese, and Pezolli,1 a rapid fluid transport system is essential for nutrient uptake and waste removal from the tooth structure. Any reduction in the rate of fluid transport through the dentin may have a deleterious effect on the health of the tooth. Under these conditions, the rate of metabolism would be altered and the end product of metabolism (lactic acid) might accumulate in the structure. The purpose of these experiments was to determine if the rate of fluid transport is related to the incidence of dental caries, to determine if the rate of fluid transport can be altered by sys-