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Module 3: Prevention of Tooth Decay

3.4 What is Fluoride, and Who Needs It?

Fluoride is a mineral that enhances tooth and bone health when provided in optimal amounts throughout life. Fluoride increases tooth resistance to tooth decay, primarily through topical effects. Fluoride occurs naturally in groundwater. It is also commonly found in foods such as breads and beverages that are made using fluoridated water and in many public fluoridated water supplies. Tooth decay can be reduced by 50 to 70 percent with exposure to the proper amounts of fluoride.

Water fluoridation is one of the best examples of a public health preventive intervention at the community level. All infants and children who drink fluoridated water benefit from systemic ingestion by incorporating fluoride into their developing teeth, as well as from important topical effects. Unfortunately, many families live in communities without fluoridated water, and many use multiple or alternative sources of water (for example, bottled or processed water), complicating the delivery of fluoride to infants and children.

Topical fluoride is probably the most important method of preventing tooth decay. Topical fluoride reaches the teeth directly, slowing down or preventing the development of tooth decay. Topical fluoride works best when it is ingested in very small amounts many times a day through water, foods containing fluoride, and fluoridated toothpaste.

Almost all toothpaste manufactured in the United States provides topical fluoride. For infants and children under age 3, beginning as soon as the first tooth erupts, parents should brush the infant's or child's teeth twice daily using a soft toothbrush that is an appropriate size for the infant's or child's age. Parents should dispense a "smear" of fluoridated toothpaste on the bristles of the toothbrush. For children ages 3 through 6, parents should brush the child's teeth or supervise brushing twice daily using a soft toothbrush that is an appropriate size for the child's age. Parents should dispense a "pea-size amount" of fluoridated toothpaste on the bristles of the toothbrush.

Another form of topical fluoride is professionally applied fluoride (including gels, foams, and varnish), which renews the high levels of fluoride in the enamel. Topical fluoride may be especially effective for children at high risk for tooth decay because they lack fluoridated water, have a history of tooth decay, snack frequently on foods containing sugar, or have a medical condition that makes them susceptible to decay. Only a dentist, dental hygienist, physician, or other qualified health professional should apply topical fluoride.