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.
Fluoride is present naturally in all water sources.1
Community water fluoridation is the process of adjusting the fluoride content of fluoride-deficient water to the recommended level for optimal dental health, which is currently recommended at 0.7 parts fluoride per million parts water.20, 21
Water fluoridation is an effective and inexpensive means of obtaining the fluoride necessary to prevent tooth decay.3
Studies show that water fluoridation continues to be effective in reducing tooth decay by 20% to 40% in children and adults, even in the era of widespread availability of fluoride from other sources, such as fluoride toothpaste.22
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.22
For those individuals, fluoride is available in other forms.
There are several ways to determine the concentration of fluoride in the water supply.3, 22
If water comes from a public or community water supply, contact the local water supplier to determine the fluoride level. Local, county or state health departments can also be a resource for this information. The U.S. Environmental Protection Agency's (EPA) website for water quality reports (called Consumer Confidence Reports
) provides information, as does the U.S. Centers for Disease Control and Prevention's (CDC) fluoridation website, "My Water's Fluoride
." The CDC website lists fluoridation status by water system for those states that have provided information.
If the water source is a private well, it will need to be tested and the results obtained from a certified laboratory.22
The local or state health department will have water sample testing information. Although the EPA does not have the authority to regulate private drinking water wells, the agency recommends that private well water be tested every year. And although the EPA does not specifically recommend testing private wells for fluoride levels, health professionals will need this information before consideration of prescription of dietary fluoride supplements or to counsel patients about alternative water sources to reduce the risk of fluorosis if the fluoride levels are above 2 ppm.
The majority of bottled waters on the market contain less than 0.3 ppm fluoride, which is less than the optimal level of fluoride.3, 11
The FDA announced in April 2019 that it is proposing to revise the quality standard for bottled water to state that bottled water to which fluoride is added by the manufacturer may not contain fluoride that exceeds 0.7 milligrams per liter (0.7 ppm).23, 24
If finalized, the proposed rule would amend the allowable levels of fluoride in domestically packaged and imported bottled water to which fluoride is added.
Some types of home water treatment systems (e.g., reverse osmosis and distillation systems) can reduce the fluoride levels in water supplies, potentially decreasing the decay-preventive effects of optimally fluoridated water; however, carbon/charcoal filtration systems do not remove fluoride.11
Dietary Fluoride Supplements
Fluoride supplements can be prescribed for children ages 6 months to 16 years who are at high risk for tooth decay and whose primary drinking water has a low fluoride concentration.2, 25
Tablets and lozenges are manufactured with 1.0, 0.5, or 0.25 mg fluoride.2, 3
Most supplements contain sodium fluoride as the active ingredient.2
To maximize the topical effect of fluoride, tablets and lozenges are intended to be chewed or sucked for 1–2 minutes before being swallowed;2, 3, 5
for infants, supplements are available as a liquid and used with a dropper.3
Dosing is based on the natural fluoride concentration of the child's drinking water and the age of the child (see Table).5, 25
All dietary fluoride supplements must be prescribed by a dentist or physician.2
For children aged younger than 6 years, health care providers should weigh the risk for tooth decay without fluoride supplements, the decay prevention offered by supplements, and the potential for dental fluorosis.2
Consideration of the child's other sources of fluoride, especially drinking water, is essential in determining this balance.3, 5
Parents and caregivers should be informed of both the benefit of protection against tooth decay and the potential risk of dental fluorosis.2
The U.S. Preventive Services Task Force recommends the clinical use of oral fluoride supplementation starting at age 6 months through 5 years for children whose water supply is deficient in fluoride.9
The recommendation is given a “B” grade, indicating that there is high certainty that the net benefit of the intervention is moderate or there is moderate certainty that the net benefit is moderate to substantial.10
Table. Fluoride Supplement (Tablets and Drops) Dosage Schedule 2010 (Approved by the American Dental Association Council on Scientific Affairs)25
Important Considerations When Using Dosage Schedule:25
|| Fluoride Ion Level in Drinking Water (ppm)*
| Birth-6 months
| 6 months-3 years
|| 0.25 mg/day**
| 3-6 years
|| 0.50 mg/day
|| 0.25 mg/day
| 6-16 years
|| 1.0 mg/day
|| 0.50 mg/day
| *1.0 part per million (ppm) = 1 milligram per liter (mg/L)
**2.2 mg sodium fluoride contains 1 mg fluoride ion
- 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 may complicate proper prescribing.
- Ingestion of higher than recommended levels of fluoride by children has been associated with an increased risk of mild dental fluorosis in developing, unerupted teeth.
- To obtain the benefits from fluoride supplements, long-term compliance on a daily basis is required.
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. Dietary fluoride supplements are not recommended for children residing in a community with adequate levels of fluoride in the water supply.
The ADA’s dietary fluoride supplement recommendations remain unchanged in light of the new guidelines for community water fluoridation in the U.S. released in April 2015 by the U.S. Public Health Service.21
for fluoride levels in drinking water was reconsidered in 2015 when it was determined that 0.7 milligrams of fluoride per liter of water (0.7 ppm) was optimal. The new recommendation, which was supported by the ADA, does not change the ADA Council on Scientific Affairs’ systematic review, clinical recommendation
and chairside guide
for the use of dietary fluoride supplements that were released in 2010.