Facts About Fluoride
Cavities used to be a fact of life. But over the past few decades, tooth decay has been reduced dramatically. The key reason: fluoride. Research has shown that fluoride reduces cavities in both children and adults. It also helps repair the early stages of tooth decay even before the decay becomes visible. Unfortunately, many people continue to be misinformed about fluoride and fluoridation. Fluoride is like any other nutrient; it is safe and effective when used appropriately. This article will help you learn more about the important oral health benefits of fluoride.
- Fluoride: Nature's Cavity Fighter
- Topical Fluorides
- Systemic Fluorides
- Fluoride Supplement Dosage Schedule—1994
- Fluoridation Information
Fluoride is a mineral that occurs naturally in all water sources, even the oceans. The fluoride ion comes from the element fluorine. Fluorine, the 17th most abundant element in the earth's crust, is never encountered in its free state in nature. It exists only in combination with other elements as a fluoride compound.
Fluoride is effective in preventing and reversing the early signs of dental caries (tooth decay). Researchers have shown that there are several ways through which fluoride achieves its decay-preventive effects. It makes the tooth structure stronger, so teeth are more resistant to acid attacks. Acid is formed when the bacteria in plaque break down sugars and carbohydrates from the diet. Repeated acid attacks break down the tooth, which causes cavities. Fluoride also acts to repair, or remineralize, areas in which acid attacks have already begun. The remineralization effect of fluoride is important because it reverses the early decay process as well as creating a tooth surface that is more resistant to decay.
Fluoride is obtained in two forms: topical and systemic. Topical fluorides strengthen teeth already present in the mouth making them more decay-resistant. Topical fluorides include toothpastes, mouth rinses and professionally applied fluoride therapies.
Systemic fluorides are those that are ingested into the body and become incorporated into forming tooth structures. Systemic fluorides can also give topical protection because fluoride is present in saliva, which continually bathes the teeth. Systemic fluorides include water fluoridation or dietary fluoride supplements in the form of tablets, drops or lozenges.
As a result of the widespread availability of these various sources of fluoride, the decay rates in both the U.S. and other countries have greatly diminished.
The proper mix is key
It is important to note that the effective prevention of dental decay requires that the proper mix of both forms of fluoride (topical and systemic) be made available to individuals. Your dentist can help you assess whether you are receiving adequate levels of fluoride for all family members from the two forms (topical and systemic).
One method of self-applied topical fluoride that is responsible for a significant drop in the level of cavities since 1960 is use of a fluoride-containing toothpaste. The American Dental Association recommends that children (over two years of age) and adults use a fluoride toothpaste displaying the ADA Seal of Acceptance or consult with a child's dentist if considering the use of toothpaste before age 2. Other sources of self-applied fluoride are mouth rinses designed to be rinsed and spit out, either prescribed by your dentist or an over-the-counter variety. The ADA recommends the use of fluoride mouth rinses, but not for children under six years of age because they may swallow the rinse.
Professionally-applied fluorides are in the form of a gel, foam or rinse, and are applied by a dentist or dental hygienist during dental visits. These fluorides are more concentrated than the self-applied fluorides, and therefore are not needed as frequently. The ADA recommends that dental professionals use any of the professional strength, tray-applied gels or foam products carrying the ADA Seal of Acceptance. There are no ADA-accepted fluoride professional rinses for use in dental offices.
Systemic fluorides such as community water fluoridation and dietary fluoride supplements are effective in reducing tooth decay. These fluorides provide topical as well as systemic protection because fluoride is present in the saliva.
Community Water Fluoridation
Fluoride is present naturally in all water sources. Community water fluoridation, which has been around for over 50 years, is simply the process of adjusting the fluoride content of fluoride-deficient water to the recommended level for optimal dental health. That recommended level is 0.7 - 1.2 parts fluoride per million parts water. Water fluoridation has been proven to reduce decay in both children and adults. While water fluoridation is an extremely effective and inexpensive means of obtaining the fluoride necessary for optimal tooth decay prevention, not everyone lives in a community with a centralized, public or private water source that can be fluoridated. For those individuals, fluoride is available in other forms.
Dietary Fluoride Supplements
Dietary fluoride supplements (tablets, drops or lozenges) are available only by prescription and are intended for use by children ages six months to 16 years living in nonfluoridated areas. Your dentist or physician can prescribe the correct dosage. It is based on the natural fluoride concentration of the child's drinking water and the age of the child (see chart). For optimum benefits, use of dietary fluoride supplements should begin when a child is six months old and be continued daily until the child is 16 years old. The need for taking dietary fluoride supplements over an extended period of time makes dietary fluoride supplements less cost-effective than water fluoridation; therefore, dietary fluoride supplements are considerably less practical as a wide-spread alternative to water fluoridation as a public health measure. Fluoride supplements are recommended only for children living in non-fluoridated areas.
It is important to note that fluoridated water may be consumed from sources other than the home water supply, such as the workplace, school and/or day care, bottled water, filtered water and from processed beverages and foods prepared with fluoridated water. For this reason, dietary fluoride supplements should be prescribed by carefully following the recommended dosage schedule (see chart). Dietary fluoride supplements are not recommended for children residing in a fluoridated community.
No matter how you get the fluoride you need -- whether it be through your drinking water, supplements, toothpaste, mouth rinse or professionally applied fluoride -- you can be confident that fluoride is silently at work fighting decay. Safe, convenient, effective...however you describe it, fluoride fits naturally into any dental care program. For more information about the oral health benefits of fluoride, just ask your dentist.
Approved by the American Dental Association, American Academy of Pediatrics and American Academy of Pediatric Dentistry
Fluoride Ion Level in Drinking Water (ppm)*
|<0.3 ppm||0.3-0.6 ppm||>0.6 ppm|
|6 months-3 years||0.25 mg/day**||None||None|
|3-6 years||0.50 mg/day||0.25 mg/day||None|
|6-16 years||1.0 mg/day||0.50 mg/day||None|
|* 1.0 ppm = 1 mg/liter
** 2.2 mg sodium fluoride contains 1 mg fluoride ion.
Important Considerations When Using Dosage Schedule:
- If fluoride level is unknown, drinking water should be tested for fluoride content before supplements are prescribed. For testing of fluoride content, contact the local or state health department.
- All sources of fluoride should be evaluated with a thorough fluoride history.
- Patient exposure to multiple water sources can make proper prescribing complex.
- Ingestion of higher than recommended levels of fluoride by children has been associated with an increase in mild dental fluorosis in developing, unerupted teeth.
- Fluoride supplements require long-term compliance on a daily basis.
Since 1956, the American Dental Association (ADA) has published Fluoridation Facts. Revised periodically, Fluoridation Facts answers frequently asked questions about community water fluoridation. In this 1998 edition, the ADA Council on Access, Prevention and Interprofessional Relations provides updated information for individuals and groups interested in the facts about fluoridation. The United States now has over 50 years of practical experience with community water fluoridation. Its remarkable longevity is testimony to fluoridation’s significance as a public health measure.
Important points to remember about fluoride and community water fluoridation are:
- Fluoridation is considered beneficial by the overwhelming majority of the health and scientific communities as well as the general public.
- Fluoride helps prevent tooth decay. All ground and surface water in the U.S. contains some naturally occurring fluoride. If a community’s water supply is fluoride-deficient (less than 0.7 parts fluoride per million parts water), fluoridation simply adjusts the fluoride’s natural level, bringing it to the level recommended for decay prevention (0.7 – 1.2 parts per million).
- Fluoridation is a community health measure that benefits children and adults. Simply by drinking optimally fluoridated water, members of a community benefit, regardless of income, education or ethnicity – not just those with access to dental care.
- Fluoridation protects over 360 million people in approximately 60 countries worldwide, with over 10,000 communities and 145 million people in the United States alone.
- As with other nutrients, fluoride is safe and effective when used and consumed properly. From time to time, opponents of fluoridation have questioned its safety and effectiveness. None of these charges has ever been substantiated by generally accepted science. After 50 years of research and practical experience, the overwhelming weight of scientific evidence indicates that fluoridation of community water supplies is both safe and effective.
- Just fifty cents per person per year covers the cost of fluoridation in an average community. Over a lifetime, that is the approximate price of one dental filling, making fluoridation very cost effective.
- Time and time again, public opinion polls show an overwhelming majority of Americans support water fluoridation.
Support for Water Fluoridation
Since 1950, the American Dental Association (ADA), along with the United States Public Health Service (USPHS), has continuously and unreservedly endorsed the optimal fluoridation of community water supplies as a safe and effective public health measure for the prevention of dental decay. The ADA’s policy on fluoridation is based on its continuing evaluation of the scientific research on the safety and effectiveness of fluoride. Over the years, the ADA has continued to reaffirm its position of support for water fluoridation and has strongly urged that its benefits be extended to communities served by public water systems. Today, fluoridation is the single most effective public health measure to prevent tooth decay and to improve oral health over a lifetime.
The American Dental Association, the U.S. Public Health Service, the American Medical Association and the World Health Organization all support community water fluoridation. Other national and international health, service and professional organizations recognize the public health benefits of fluoridation
Scientific Information on Fluoridation
The ADA’s policies regarding community water fluoridation are based on generally accepted scientific knowledge. This body of knowledge is based on the efforts of nationally recognized scientists who have conducted research using the scientific method, have drawn appropriate balanced conclusions based on their research findings and have published their results in refereed (peer-reviewed) professional journals that are widely held or circulated. Confirmation of scientific findings also reinforces its validity of existing studies.
From time to time, opponents of fluoridation have questioned its safety and effectiveness. None of these charges has ever been substantiated by generally accepted science.
History of Water Fluoridation
Research into the beneficial effects of fluoride began in the early 1900s. Frederick McKay, a young dentist, opened a dental practice in Colorado Springs, Colorado, and was surprised to discover that many local residents exhibited strange brown stains on their permanent teeth. McKay could find no documentation of the condition in the dental literature and eventually convinced Dr. G.V. Black, an expert on dental enamel, to study the condition. Through their research, Black and McKay determined that mottled enamel, as Black termed the condition, resulted from developmental imperfections in teeth. (Mottled enamel is a historical term. Today, this condition is called severe dental fluorosis.) Black and McKay also noted that these stained teeth were surprisingly resistant to decay.
Following years of observation and study, McKay determined that it was high levels of naturally occurring fluoride in the drinking water that was causing the mottled enamel. McKay’s deductions were researched by Dr. H. Trendley Dean, a dental officer of the U.S. Public Health Service. Dean designed the first fluoride studies in the United States. These early studies were aimed at evaluating how high the fluoride levels in water could be before visible, severe dental fluorosis occurred. By 1936, Dean and his staff had made the critical discovery that fluoride levels of up to 1.0 part per million (ppm) in the drinking water did not cause mottling, or severe dental fluorosis. Dean additionally noted a correlation between fluoride levels in the water and reduced incidence of dental decay. Following Dean’s initial findings, community-wide studies were carried out to evaluate the addition of sodium fluoride to fluoride-deficient water supplies. The first community water fluoridation program began in Grand Rapids, Michigan, in 1945.
Water Fluoridation as a Public Health Measure
Throughout decades of research and more than fifty years of practical experience, fluoridation of public water supplies has been responsible for dramatically improving the public’s oral health status. In 1998, recognizing the ongoing need to improve health and well being, the U.S. Public Health Service revised national health objectives to be achieved by the year 2010. Included under oral health was an objective to significantly expand the fluoridation of public water supplies. In 1994, the U.S. Department of Health and Human Services issued a report which reviewed public health achievements. Along with other successful public health measures such as the virtual eradication of polio and reductions in childhood blood lead levels, fluoridation was lauded as one of the most economical preventive values in the nation. Finally, a policy statement on water fluoridation reaffirmed in 1995 by the USPHS stated that water fluoridation is the most cost-effective, practical and safe means for reducing the occurrence of tooth decay in a community.
Simply by drinking optimally fluoridated water, the entire community benefits regardless of age, socioeconomic status, educational attainment or other social variables. Community water fluoridation does not discriminate against anyone based on income, education or ethnicity. Fluoridation’s benefits are realized without behavior change on the part of an individual. The benefits of water fluoridation are not limited to those with access to dental care.
Water Fluoridation’s Role in Reducing Dental Decay
Water fluoridation and the use of topical fluoride have played a significant role in improving oral health. Studies show that water fluoridation can reduce the amount of cavities children get in their baby teeth by as much as 60%; and can reduce tooth decay in permanent adult teeth by nearly 35%. Increasing numbers of adults are retaining their teeth throughout their lifetimes due in part to the benefits they receive from water fluoridation. Dental expenditures for these individuals are likely to have been reduced and innumerable hours of needless pain and suffering due to untreated dental decay have been avoided.
It is important to note that dental decay is caused by dental plaque, a thin, sticky, colorless deposit of bacteria that constantly forms on teeth. When sugar and carbohydrates are eaten, the bacteria in plaque produce acids that attack the tooth enamel. After repeated attacks, the enamel breaks down, and a cavity (hole) is formed (see Tooth Decay). There are several factors that increase an individual’s risk for decay:
- Recent history of dental decay
- Elevated oral bacteria count
- Inadequate exposure to fluorides
- Exposed roots
- Frequent sugar and carbohydrate intake
- Fair to poor oral hygiene
- Inadequate saliva flow
- Deep pits and fissures in the chewing surfaces of teeth
Exposure to fluoride is not the only measure available to decrease the risk of decay. In formulating a decay prevention program, a number of intervention strategies may be recommended.
Ongoing Need for Water Fluoridation
Because of the decay risk factors noted previously, many individuals and communities still experience high levels of dental decay. Although water fluoridation demonstrates an impressive record of effectiveness and safety, only 62.2% of the United States population on public water supplies receives fluoridated water containing protective levels of fluoride. 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.