Fluoride: Nature's Own Cavity Fighter

Have you ever wondered what fluoride actually is and how it works to fight cavities?

In order to better understand how fluoride helps to prevent tooth decay, it is important to first understand how a cavity is formed. Each day a dynamic process takes place where minerals are released out of the tooth structure into the saliva when oral pH drops below 7, and then are taken back up into the tooth once oral pH returns to 7 or above. This pH change happens due to a number of factors. For example, many of the foods we eat are acidic in nature, such as coffee, fruits, etc. As we eat these types of foods they cause the overall oral pH to drop to a level conducive to the release of minerals from our teeth.

Additionally, some of the bacteria which reside in our mouths and colonize on our tooth surfaces eat sugars found in the foods that we consume and create an acidic byproduct called plaque, a sticky white substance that encapsulates the bacteria which reside within it. The plaque becomes increasingly acidic if it is not removed regularly from the tooth surfaces. This pH drop is of particular concern when considering that many people have root exposure due to recession. The root material consists of a softer tooth structure called dentin which is more susceptible to the acid damage.

  

Minerals are released from dentin as the pH of your mouth drops from 7 to 6.7 and below. Enamel, which is said to be the body's hardest structure, requires oral pH to drop lower, to 5.5 or below, before its minerals are released through demineralization. Over time, with repeated acid attack, weak areas known as decalcifications develop that are basically porous areas on the tooth surface where minerals are missing. These decalcified areas sometimes appear as a chalky white or frosted spot on the tooth.

If acid exposure continues and the mouth is not allowed to stay at a pH level that is conducive to remineralization, these porous areas will eventually break down enough to form a small hole also known as a cavity. Before a true cavity is formed, fluoride, along with effective plaque removal and dietary changes, can facilitate the remineralization process.

So where does fluoride come in?

Fluoride is a naturally occurring active ion found in water and foods, formed from the element fluorine. When fluoride is applied to teeth, fluoride ions are drawn to areas that are weak and missing minerals. After adhering to these areas, fluoride will attract calcium and phosphate back to the tooth surface and repair the porous area, a process called remineralization. Research has shown that areas which have been remineralized with fluoride form a harder more acid resistant mineral compound, called fluorapatite, than teeth's normal mineral compound, hydroxyapatite. 

Not only is fluoride helpful to protect and strengthen our teeth it is very economical. It costs around $0.50 per year per person to fluoridate our water supply to a safe level for consumption of around 0.7-1.2, depending on the geographical climate.¹ Over the counter toothpaste carries an average cost of around $2.50 per tube consisting of approximately 1,000-1,500 parts per million (ppm).² The highest concentration of fluoride can only be applied professionally by a trained dental professional with a cost of around $25-30 per application and a concentration in the range of 11,000-24,000 ppm.  Taking these preventative measures will cost considerably less than a typical dental filling to restore a formed cavity at an average cost of $101.94, as well as conserving your natural tooth structure and leading to a healthier mouth throughout your life.³

Vanessa Childress, Hygienist 

Terry O'Shea DDS, PC

Photo #1- compendiumlive.com. Web. 28 May 2011.

Photo #2- Roberts, Michael, and Timothy Wright. "The Dynamic Process of Demineralization and Remineralization." Dimensions of Dental Hygiene n. pag. Web. 28 May 2011. <http://www.dimensionsofdentalhygiene.com/ddhright.aspx?id=5380>.

¹"Achievements in Public Health, 1900-1999: Fluoridation of Drinking Water to Prevent Dental Caries." Morbidity and Mortality Weekly Report 48.41 (1999): 933-940. Web. 28 May 2011. <http://www.cdc.gov/mmwr/preview/mmwrhtml/mm4841a1.htm>.

²"Community Water Fluoridation." Center for Disease Control and Prevention. CDC, 06012011. Web. 28 May 2011. <http://www.cdc.gov/fluoridation/other.htm>.

³"10 Reasons to Fluoridate Public Water ." American Dental Association. N.p., n.d. Web. 28 May 2011. <http://www.ada.org/sections/newsAndEvents/pdfs/article_10reasons.pdf>.