ABSTRACT
The interest of dental investigators and practitioners has since started to focus on posteruptive or topical effects of fluoride, while the systemic effects have been studied on a limited basis only. The distinction between the systemic and topical benefit is important with respect to the fluoridation of domestic salt and the use of fluoride tablets. The systemic effect of fluoride is most apparent in water fluoridation studies. Deatherage first suggested that protection may diminish or disappear when fluoride supplementation is discontinued. The present analysis indicates that systemic fluorides are important for obtaining maximum benefit regarding pit and fissure caries and, to a lesser degree, regarding approximal surfaces. An international workshop on cariostatic mechanisms of fluorides held in 1976 distinguished between physico-chemical aspects within the enamel on the one hand and biochemistry and microbiology of plaque on the other. The cariostatic effectiveness of many methods of topical fluoridation has been assessed with remarkable precision.
