10 American Dental Association hours of needless pain and suffering due to untreated tooth decay have been avoided. By preventing tooth decay, community water fluoridation has been shown to save money, both for families and the health care system. The return on investment for community water fluoridation varies with size of the community, and in general, increases as the community size increases. Community water fluoridation is cost- saving, even for small communities. Additional information about this topic can be found in the Cost Section, Question 68. Fluoridation of community water supplies is the single most effective public health measure to prevent tooth decay. Studies show that community water fluoridation prevents at least 25 percent of tooth decay in children and adults, even in an era with widespread availability of fluoride from other sources, such as fluoride toothpaste. Community water fluoridation is a most valuable public health measure because: • Optimally fluoridated water is accessible to the entire community regardless of socioeconomic status, educational attainment or other social variables.51 • Individuals do not need to change their behavior to obtain the benefits of fluoridation. • Frequent exposure to small amounts of fluoride over time makes fluoridation effective through the life span in helping to prevent tooth decay.52 • Community water fluoridation is more cost- effective and cost-saving than other forms of fluoride treatments or applications.53,54 Tooth decay is caused by sugars in snacks, food and beverages being converted into acid by the bacteria in dental plaque, a thin, sticky, colorless deposit on teeth. The acid attacks the tooth enamel (the hard surface of the tooth) or root surface. After repeated attacks, the enamel or root surface loses minerals (demineralization) and the acids and bacteria penetrate the dentin and finally the pulp. The soft tissue of the pulp contains nerves and blood vessels. Once the decay enters the pulp, it becomes infected and without treatment, the infection progresses and travels into the surrounding tissues. It can enter the bloodstream and potentially spread the infection to other parts of the body which can be life-threatening. Additional information about this topic can be found in the Benefits Section, Question 2. There are a number of factors that increase an individual’s risk for tooth decay:54-59 • Recent history of tooth decay • Elevated oral bacteria count • Inadequate exposures to fluorides • Exposed roots • Frequent intake of sugar/sugary foods and sugar-sweetened beverages • Poor or inadequate oral hygiene • Decreased flow of saliva • Deep pits and fissures on the chewing surfaces of teeth Exposure to fluoride is a key component in any recommended decay prevention strategy however, the use of fluoride alone will not prevent all tooth decay. In formulating a decay prevention program, in additional to consuming fluoridated tap water, a number of intervention strategies may be considered such as improved daily home care, reducing sugar in the diet, placement of dental sealants and prescription strength fluoride toothpaste for home use and professionally applied topical treatments. Ongoing Need for Water Fluoridation Because of the risk factors for tooth decay noted previously, many individuals and communities still experience high levels of tooth decay. Although water fluoridation demonstrates an impressive record of effectiveness and safety, only 74.4% of the United States population on public water supplies in 2014 received fluoridated water containing protective levels of fluoride.48 Unfortunately, some people continue to be confused about this effective public health measure. If the number of individuals drinking fluoridated water is to increase, the public must be accurately informed about its benefits and safety.