Posts for tag: fluoride
We know from research extending back to the 1930s that very small amounts of fluoride in drinking water can significantly reduce dental caries (cavities) with no negative health effects. Fluoridated water is currently available to 70% of all Americans. However, we have also learned that excess fluoride from combined sources can result in staining of teeth called “fluorosis.”
What is the optimum fluoride concentration for healthy teeth?
A fluoride concentration of about 0.7-1.20 milligrams per liter (mg/L), or .7 to 1.2 ppm (parts per million), in the water supply seems to be optimum for dental health without causing negative effects. This concentration is about the same as a grain of salt in a gallon of water. An amount of 1 ppm was originally considered the safe standard, but since today Americans have access to more sources of fluoride than they did when water fluoridation was first introduced, the recommended amount has been reduced to .7 mg/L or .7 ppm.
The crucial amount to measure is the quantity of fluoride that is swallowed. Generally, the optimal level of fluoride per day from all sources is thought to be about .06 milligrams per kilogram of body weight, or about a sixth of the weight of a grain of salt for every two pounds of body weight.
It is probably not possible to calculate the precise amount of fluoride each person ingests per day, because the amount depends on more than just the amount of tapwater you drink. Bottled waters, soft drinks and juices also contain fluoride. Breast milk and cow's milk are very low in fluoride, but infant formulas may contain higher levels. Foods found to have high fluoride content include teas, dry infant cereals and processed chicken, fish and seafood products. Toothpaste can contribute to a child's total fluoride intake if the child swallows it.
What are the effects of too much fluoride?
Dental fluorosis produces a “mottling” of the outer coating of the tooth, the enamel. Mottling may show as staining ranging from small white striations to stained pitting and severe browning of the enamel surface.
The first six to eight years of life is the most risky time for development of dental fluorosis. Parents need to monitor their children to make sure they use small amounts of fluoride toothpaste (an amount the size of a pea on the brush is recommended). Watch for white spots on the enamel (hard outside coating) of your child's teeth. White spots from fluorosis mean it is time to pay attention to how much fluoride your child is getting from various sources, and to cut back on the total. You want fluoride's protection against cavities for your child's teeth, without the unsightliness of dental fluorosis from too much fluoride.
Contact us today to schedule an appointment to discuss your questions about fluoride. You can also learn more by reading the Dear Doctor magazine articles “Fluoride & Fluoridation in Dentistry” and “New Fluoride Recommendations.”
Guidelines regarding the concentration of fluoride in water have recently been changed by the US Government's Department of Health and Human Services (HHS) and the Environmental Protection Agency (EPA). These agencies recommended a reduction of fluoride in water supplies to 0.7mg/L, modifying the original recommendations provided in 1962 by the US Public Health Service.
What is fluoride, and why add it to water supplies?
Fluoride is a chemical form of fluorine, a naturally occurring element. For decades, scientists have carried out studies on the effects of fluoride in water, and they have proved that fluoride strengthens tooth surfaces and makes them resistant to decay. A fluoride concentration of about one milligram per liter (1 mg/L), or 1 part per million (1ppm), in the water supply is associated with substantially fewer cavities. This concentration of fluoride (equivalent to a grain of salt in a gallon of water) has been found to have no negative health effects.
The Center for Disease Control (CDC) says that fluoridated water is one of the ten most effective public health measures of the 20th Century. The optimal amount of fluoride necessary to make teeth resistant to decay turns out to be between 0.7 and 1.20 milligrams per liter (mg/L). A certain amount of fluoride occurs naturally in water supplies, and communities have added fluoride to bring the amount up to the optimal recommendations.
How does fluoride you drink get into your teeth?
The fluoride you drink in your water is deposited in your bones. Bone is an active living substance that is constantly broken down and rebuilt as a normal body process. As this happens the fluoride is released into the blood, from which it can enter the saliva and act on the tooth surface.
What about fluoride from other sources?
Americans now have access to many sources of fluoride in addition to the water they drink. These include foods, beverages and toothpaste. As a result, dentists have begun to notice an increased prevalence of a condition known as Dental Fluorosis.
What is Dental Fluorosis?
Dental Fluorosis can occur when teeth, particularly in children, receive too much fluoride. This condition is a mottling or uneven staining of the tooth surface enamel. There may be small white spots or extensive brownish discolorations. The mottled enamel is still resistant to decay, but it may be unattractive in appearance.
What is the idea behind the new guidelines?
With the new guidelines, fluoride is kept at the lower end of the scale of the optimal concentration for strengthening teeth against decay. At this end, there is room to add consumption of fluoride from other sources such as foods or toothpaste. In short, it is the best of both worlds.
Contact us today to schedule an appointment to discuss your questions about fluoride. You can learn more by reading the Dear Doctor magazine articles “Fluoride & Fluoridation in Dentistry” and “New Fluoride Recommendations.”
The CDC (Centers for Disease Control and Prevention) calls fluoridation of drinking water one of the ten most important public health measures of the 20th century, along with such measures as vaccination and motor-vehicle safety.
A fluoride concentration of about one milligram per liter (1 mg/L), or 1 part per million (1ppm), in the water supply is associated with substantially fewer cavities. This concentration of fluoride (equivalent to a grain of salt in a gallon of water) has been found to have no negative health effects.
The connection between fluoride and oral health was confirmed in the first half of the 20th century, and by 1955 the first clinically proven fluoride toothpaste was launched. Fluoride-containing toothpastes are common today, along with other fluoride-containing products.
Protective Effects of Fluoride
Ongoing studies have shown that fluoride has both a systemic (through the body) effect and a local effect at the tooth surfaces. Tooth decay takes place as part of a kind of active war between de-mineralization and re-mineralization, in which acids produced by bacteria in plaque (a biofilm in your mouth) soften and dissolve the minerals (de-mineralization) in the tooth's surface. At the same time, the saliva bathing the tooth acts to re-harden the tooth's surface by adding minerals back (re-mineralization). If fluoride is present in the biofilm and in the saliva, it protects against de-mineralization.
The fluoride you drink in your water is deposited in your bones. Bone is an active living substance that is constantly broken down and rebuilt as a normal body process. As this happens the fluoride is released into the blood, from which it can enter the saliva and act on the tooth surface. The fluoride in toothpastes and products like rinses is delivered directly to the tooth surface. Fluorides can also be eaten in foods with high fluoride content such as teas, dry infant cereals and processed chicken, fish and seafood products.
Problems with Over-use
Eating or swallowing too much fluoride can contribute to a discoloration of teeth called dental fluorosis, which varies in appearance from small white striations to stained pitting and severe brown mottling of the enamel. To avoid this effect, monitor children's tooth brushing to make sure they use only a small amount of fluoride toothpaste and do not swallow it.
Adding fluoride to water has been controversial because some people believe that it may cause other harmful effects. However, most health experts believe that fluoridated water carries no significant health risks and significantly contributes to public health by preventing tooth decay.