Current models for increasing the anti-caries effects of
fluoride (F) agents emphasize the importance of maintaining a cariostatic concentration of F in oral fluids. The concentration of F in oral fluids is maintained by the release of this ion from bioavailable reservoirs on the teeth, oral mucosa and - most importantly, because of its association with the caries process -
dental plaque. Oral F reservoirs appear to be of two types: (1)
mineral reservoirs, in particular
calcium fluoride or
phosphate-contaminated '
calcium-fluoride-like' deposits; (2)
biological reservoirs, in particular (with regard to
dental plaque) F held to bacteria or bacterial fragments via
calcium-fluoride bonds. The fact that all these reservoirs are mediated by
calcium implies that their formation is limited by the low concentration of
calcium in oral fluids. By using novel procedures which overcome this limitation, the formation of these F reservoirs after topical F application can be greatly increased. Although these increases are associated with substantive increases in salivary and plaque fluid F, and hence a potential increase in
cariostatic effect, it is unclear if such changes are related to the increases in the amount of these reservoirs, or changes in the types of F deposits formed. New techniques have been developed for identifying and quantifying these deposits which should prove useful in developing agents that enhance formation of oral F reservoirs with optimum F release characteristics. Such research offers the prospect of decreasing the F content of topical agents while simultaneously increasing their
cariostatic effect.