The level and timing of systemic exposure to fluoride with respect to caries resistance.

Material related to water fluoridation and fluoride availability has been examined for changing patterns of fluoride intake by humans over recent years. The difficulty of separating systemic and topical fluoride action from water and foods from that found in fluoride agents used in preventive treatment programs is discussed. Recommendations are made that water fluoridation is a well-proven program and should be continued, but that fluoride supplementation programs under the control of the individual should be carefully evaluated and, if used, should be restricted to periods after the secretory stage of enamel formation is normally finished for anterior teeth, with supplements commenced during the pre-eruption maturation period and continuing until permanent tooth eruption is complete. Although supplements can also give a topical source to the teeth, depending on the way the supplement is consumed and the duration of time it is available in the mouth, other methods of topical fluoride provision are endorsed, and these should continue through life. It is suggested, in respect of epidemiology studies, that data collected before the availability of fluoride dentifrices in 1971 should be re-examined.