Fluoride has been shown to reduce the incidence of dental caries. Cariogenic bacteria produce acids which damage the structural integrity of tooth enamel. Through demineralization, the bacteria dissolve the hard surfaces of the tooth, causing the loss of calcium, phosphate, and carbonate. This compromises the enamel's protective ability to prevent bacteria from reaching the dentin and pulp tissue, resulting in tooth decay. Fluoride, when concentrated in dental plaques, facilitates remineralization of the tooth and produces a more acid-resistant structure as well.

Community water fluoridation, monitored at optimum levels of 0.7-1.2 g/mL or ppm, has been shown to be a safe and effective means of reducing dental caries in the general population. The Office of the Surgeon General, in a fact sheet outlining the benefits of fluoride, describes the cost-effectiveness of this intervention, considered to be one of ten great public health achievements of the 20th century. Currently, fluoridated water reaches 170 million Americans, approximately 67% of the population served by public water supplies, with 75% being one of the targeted goals of Healthy People 2010.

Percent of Population on Fluoridated Public Water

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