What we know and do not know about fluoride

Summary There is much that we know about fluoride as it relates to human health in general and dental health in particular. Some of the information that is known concerning water fluoridation and dental fluorosis is listed. What we do not know about fluoride is discussed in more detail, namely the efficacy of lower levels of fluoride in drinking water, the effect of discontinuing fluoride in drinking water in the absence of additional preventive measures, the prevalence of fluorosis and whether or not this presents a cosmetic problem. Other issues discussed include the actual amount of fluoride ingested from all sources, whether low-fluoride dentifrices are as efficacious as conventional dentifrices in caries protection and reducing enamel fluorosis, the role of socioeconomic factors in determining caries prevalence, and the effects of bottled water use on caries prevalence in fluoridated communities.