Is Water Fluoridation Effective?
Prior to the wide-spread use of water fluoridation, 98 out of 100 Americans experienced some tooth decay by the time they reached adulthood. In the 1940s, with the advent of public water fluoridation, there began a 56% reduction in caries for children 12 -14 years of age (Dunning, 1979). In general, children showed a 20 – 40 % caries reduction over a lifetime (U.S. Health and Human Services, 1994).
Fluoridation of public water supplies is a safe, economical, and effective measure to prevent dental caries.
Community water fluoridation is an effective, safe, and inexpensive way to prevent tooth decay. This method of fluoride delivery benefits Americans of all ages and socioeconomic status.
In regions where only 19% of the population is served with fluoridated water [Oregon 20%], the difference in caries scores between fluoridated and nonfluoridated areas was 61%. In regions where 74% of the population is served with fluoridated water, the difference was only 6%. These findings suggested an important role for the halo or diffusion effect [nonfluoridated communities benefit from the products produced in nearby fluoridated communities, effectively reducing the disparity].
Research provides conclusive evidence that fluoridation of the water supply or supplemental fluoride reduces dental caries, and of all dietary components exhibiting a protective effect against caries, the most effective is fluoride. Fluoridated drinking water increases resistance to dental caries at all ages. The earlier that children are exposed to fluoridated drinking water or dietary fluoride supplements the greater the reduction in dental caries in both the primary and permanent teeth.