What is Fluoride?

Categories: General Dentistry


Fluoride is a naturally occurring ionic compound of the element Fluorine. Since Fluorine is the thirteenth most abundant element in the earth’s crust, it is fairly common and is present in most water and plants in varying but usually small amounts.

Since the 1950s, the United States government has made it a policy to make sure that most drinking water has fluoride in it at a quantity of about 1 part per million, which usually takes the form of adding it to water which has less than that and filtering out fluoride where it is found in greater abundance. The government does this because of the demonstrated advantages that fluoride in this concentration gives to oral health. What are these advantages?

Fluoride and dental health: a history

In 1901, a recent dental-school graduate named Frederick McKay decided to set up practice in Colorado Springs. He soon noticed an interesting phenomenon: a large percentage of his patients had tooth enamel that was slightly to severely discolored, with some showing only slight opaque white patches and others teeth that had a yellowish or brownish cast and brown-colored pits on their surface. He also noticed that, other than the discoloration, his patients had remarkably strong teeth that were largely freed of cavities.

McKay began collecting reports of similar dental phenomenon and tried to trace their source. Ultimately, he discovered that in areas where these unusually strong, cavity-free but stained teeth were common, the water supply had a very high concentration of fluoride. This soon became a cause for great concern, as few cherished the idea of their drinking water staining their teeth, a condition which became known as dental fluorosis.

However, further investigations over the 1920s and 1930s revealed first that staining happened only in those who had been born and spent their early childhoods in these high-fluoride water areas. On the other hand, in regions where the water fluoride was between .05 and 1 part-per-million, teeth did not present severe staining, with fewer that 10 percent of those who drank it showing any stains at all (and most of those who did experience a discoloration only showed small, barely visible white patches described above). However, dental cavities in all these areas were far less prevalent than the national average. What is more, the low cavity rate was even found in those who had come to these places from elsewhere, showing a connection between fluoride of about 1 part per million and stronger teeth.

In the mid-1940s, Grand Rapids, Michigan and Newburgh, New York (cities which had almost no naturally-occurring fluoride in their water) agreed to have fluoride added to their water and have the results studied. These results were startling: discoloration was practically negligible, but cavities in Grand Rapids dropped by up to 43 percent within six years (Newburgh had similar results). By the 1950s, fluoridation of drinking water became national policy, and repeated studies continue to show the benefits in the form of stronger teeth.

How does fluoride affect dental health?

Essentially, cavities are caused by acid wearing holes into the enamel of teeth. This occurs because the mouth contains a bacteria called Streptococcus mutans. Streptococcus mutans produces lactic acid, which it does by metabolizing chemicals called “sugars”, including sucrose (which is present in actual sugar), as well as fructose (a chemical similar to sucrose that is found in fruits), glucose (which is present in breads and other starches), and lactose (which is in milk and dairy products.

The eating of most foods will therefore lead to the creation of lactic acid, and this causes tooth enamel to demineralize. However, this demineralization is countered by “remineralization”, whereby the enamel is strengthened by ions of calcium and phosphate which rebuild tooth enamel. These ions are created by the body and carried in saliva. Fluoride helps with this in two ways. First, fluoride is considered to be a chemical base. Such chemicals act to neutralize acid. Second, fluoride encourages these calcium and phosphate ions to bind with tooth enamel.

Fluoride’s cavity fighting properties are apparently topical, and therefore do not depend on ingestion. In other words, contact between fluoride and teeth alone is enough to confer these benefits, and the fluoride does not necessarily need to be consumed and digested. In most of Europe, fluoride is not added to water supplies, but is added to salt and is put in toothpaste, with similar results to the United States. However, fluoridation of water shows no documented ill-effects, and it affects neither the taste, smell, or clarity of water.

The Benefits of Fluoride

American drinking water nowadays is treated in just such a way to give it the ideal concentration (around 1 part per million), which means reducing it in some water – like what used to be present in Colorado Springs in 1901- and adding it to others. At this ideal concentration, fluoride confers substantial protection from cavities, and is an excellent aid to overall dental health.

Please call Ebrahimian Integrative Dentistry at (831) 824-5111 or contact us online to request an appointment today.