Author: Shirley Chen
Fluoride is an ionic form of fluorine and an inorganic mineral found naturally in water, soil, rocks, foods, and plants (Canadian Dental Association, n.d.; Cafasso, 2019; National Institute of Health, 2021). With the appropriate amount, fluoride can strengthen your teeth and decrease the risk of caries (tooth decay) (Canadian Dental Association, n.d.; Cafasso, 2019; National Institute of Health, 2021; American Dental Association, 2019). Teeth are made up of 3 layers: enamel on the outside, dentin in the middle, and the pulp chamber on the inside. Enamel is made up of a mineral called hydroxyapatite, and tooth decay begins with the loss, or demineralization, of enamel (Aoun et. al., 2018).
So how does demineralization occur? It is due to acid. Acid can come from ingesting acidic foods such as lemons, but it can also be produced by bacteria as they feed on simple carbohydrates (Cafasso, 2019; National Institute of Health, 2021; Aoun et. al., 2018). In acidic conditions, enamel begins to break down and soften, decreasing enamel’s protective properties. If this process is not stopped or reversed, it will lead to cavities and damage to the dentin, then the pulp, causing sensitivity, pain, and even death of the tooth.
The opposite of demineralization is remineralization, which leads to the hardening of enamel (Cafasso, 2019; American Dental Association, 2019; Aoun et. al., 2018). Every tooth is constantly undergoing demineralization and remineralization, and the balance of these two processes depends on the acidity of the environment in the mouth. If the acidity is past a certain threshold, demineralization dominates; if the acidity is below the threshold, remineralization dominates.
The good news is that at the start of demineralization, before a cavity forms, there are ways to stop and reverse demineralization and avoid the need for a filling. You can maintain good oral hygiene and reduce the intake of acidic foods and simple carbohydrates that allow bacteria to grow and produce acid. If you do ingest these foods, using water to rinse your mouth soon after helps wash the acids off the teeth. Another way to encourage remineralization is to strengthen the enamel with fluoride. In teeth, fluoride can turn hydroxyapatite into fluorapatite, which is more resistant to acid and therefore reduces the risk of caries (Canadian Dental Association, n.d.; Cafasso, 2019; National Institute of Health, 2021; American Dental Association, 2019; Aoun et. al., 2018).
A major source of fluoride for many communities is water. However, there are other sources of fluoride available. Many toothpaste brands offer products with fluoride, including Crest, Sensodyne and Colgate, and they are great sources of topical fluoride for the teeth. There are also fluoridated mouth rinses from brands such as Listerine. During a dental visit, the dentist can also apply fluoride gels that are higher in fluoride concentration than over-the-counter fluoridated products (American Dental Association, 2019).
As with most things, there is an optimal amount of fluoride one should have. Excessive intake of fluoride can lead to dental fluorosis, which is a change in tooth appearance that happens when excessive amounts of fluoride are ingested in early childhood (Canadian Dental Association, n.d.), and gastrointestinal upset. The recommended amount of fluoride intake is: 0.01mg/day from ages 0-6 months; 0.5mg/day from ages 7-12 months; 0.7mg/day from ages 1-3 years; 1mg/day from ages 4-8 years; 2mg/day from ages 9-13 years; 3mg/day from ages 14-18 years; 3mg/day for females aged 19+; and 4mg/day for males aged 19+ (National Institute of Health, 2021; Aoun et. al., 2018).
With the right amount, fluoride is very beneficial to dental health. By aiding in the conservation of tooth structure, fluoride helps with the maintenance of oral function for speaking, eating, and expressing emotions, as well as the preservation of your beautiful smile.
American Dental Association. (2019). Fluoride: Topical and Systemic Supplements. Retrieved April 11, 2021, from https://www.ada.org/en/member-center/oral-health-topics/fluoride-topical-and-systemic-supplements.
Aoun, A., Darwiche, F., Al Hayek, S., & Doumit, J. (2018). The Fluoride Debate: The Pros and Cons of Fluoridation. Preventive nutrition and food science, 23(3), 171–180. https://doi.org/10.3746/pnf.2018.23.3.171.
Cafasso, J. (2019). What if fluoride, and is it safe? Retrieved April 11, 2021, from https://www.healthline.com/health/what-is-fluoride.
Canadian Dental Association. (n.d.). Fluoride FAQs. Retrieved from https://www.cda-adc.ca/en/oral_health/faqs/fluoride_faqs.asp.
National Institute of Health. (2021). Fluoride. Retrieved April 11, 2021, from https://ods.od.nih.gov/factsheets/Fluoride-HealthProfessional/.