Fluoride as a protective factor for tooth decay.

There is abundant scientific evidence that demonstrates that fluoride strengthens the teeth, makes them less susceptible to acid attacks, and inhibits the production of acids by cavity-causing bacteria. The evidence for the anticaries efficacy of daily fluoride use is strong.[1] Tooth structure is primarily made up of the mineral hydroxyapatite, which demineralizes when the oral pH drops at or below 5.5. When the teeth are under an acid attack and fluoride is present during the remineralization process, hydroxyapatite particles combine with fluoride to form fluorapatite within the tooth structure. Fluorapatite is more resistant to acid attacks than hydroxyapatite as it does not begin to dissolve or demineralize until the pH drops to or below 4.5. In the window of pH 4.5–5.5 (See Figure 14), hydroxyapatite is dissolving in the enamel and fluorapatite is forming. As the pH cycles in a healthy balance in the mouth, in the presence of fluoride, this window of pH accounts for maturation of the enamel, making it stronger and more decay resistant (see See Figure 3).

Fluoride comes in many forms and concentrations. Neutral sodium fluoride can be used as a protective factor, and it comes in many concentrations and many different types of products. The most common are the following:

Based on your caries risk assessment, your dental professional will recommend proper products. For adults and children 6 years of age and older, any level of fluoride is considered safe and recommendations are made based on the patient’s caries risk level. For children aged 2–5, the American Academy of Pediatric Dentistry recommends a pea-sized amount of 0.243% fluoride toothpaste/gel daily.[2] For children under age 2, due to the risk of fluorosis, other protective agents such as pH neutralization, xylitol, and nanoparticles of hydroxyapatite should be explored. Fluorosis results from higher-than recommended levels/doses of fluoride exposure and appears as unsightly white spots or even brown spots on the teeth. The greatest amount of therapeutic remineralization scientific evidence involves the use of fluoride. Numerous studies demonstrate the value of fluoride in the remineralization process.[3, 4, 5]

  1. G. Topping and A. Assaf, “Strong Evidence That Daily Use of Fluoride Toothpaste Prevents Caries,” Evid Based Dent 6, no. 2 (2005): 32.
  2. American Academy of Pediatric Dentistry Council on Clinical Affairs, “Guideline on Infant Oral Health Care,” AAPD Reference Manual 33(2011): 6–11/12.
  3. J. M. Ten Cate and J. D. Featherstone, “Mechanistic Aspects of the Interactions between Fluoride and Dental Enamel,” Crit Rev Oral BiolMed 2, no. 3 (1991): 283–96.
  4. J. D. Featherstone, R. Glena, M. Shariati, and C. P. Shields, “Dependence of In Vitro Demineralization of Apatite and Remineralization of Dental Enamel on Fluoride Concentration,” J Dent Res 69 (1990):620–625.
  5. A. Dasanayake and P. W. Caufield, “At-Home or In-Office Fluoride Application Does Not Significantly Reduce Subsequent Caries-Related Procedures in Ambulatory Adults of Any Caries-Risk Level,” J Evid Base Dent Practice 7 (2007): 155–157.