Fluoride is an important mineral that helps prevent tooth decay and cavities. It is added to many public drinking water supplies and is also an ingredient in most toothpastes. Fluoride works by strengthening the tooth enamel, making teeth more resistant to acid attacks that can lead to cavities. But some people wonder if fluoride merely sits on the surface of teeth, meaning it can come off or wear away over time. Let’s take a closer look at how fluoride interacts with tooth enamel and whether it does in fact come off teeth.
How fluoride strengthens teeth
When fluoride is present in the mouth, it gets incorporated into the tooth enamel as teeth are developing. Fluoride becomes part of the hydroxyapatite crystals that make up enamel. This changes the physical structure of the enamel, making it more resistant to acid and decay. Fluoride also continues to be incorporated into existing enamel throughout life by remineralizing the tooth surface. So fluoride does not simply coat the surface of teeth, it becomes an integral part of the enamel itself.
Does fluoride wear off teeth?
Because fluoride is incorporated into the enamel’s crystalline structure, it does not wash off or wear away under normal circumstances. The only way fluoride comes off teeth is when the enamel itself starts to break down, such as in the beginning stages of cavities. As cavities progress, the enamel breaks down and can release some of its fluoride content. But on a healthy tooth surface, the fluoride is fixed firmly within the enamel.
However, the fluoride in saliva and toothpaste that has not yet been incorporated into enamel can be temporary. This type of topical fluoride may come off teeth more readily through eating, drinking, and saliva flow. But it can be easily replenished by using fluoridated toothpaste, mouthwash, or drinking fluoridated water.
Fluoride and dental visits
Some dental cleanings and procedures may remove small amounts of fluoride along with enamel. Methods like tooth scaling and polishing are aimed at removing plaque and tartar, but they can also take off tiny layers of enamel. This enamel then regenerates over time, replenishing the fluoride lost. Fluoride applications at the dental office can also help make up for any losses during cleanings.
Factors that affect how much fluoride teeth retain
Certain factors affect how well fluoride is incorporated into enamel and retained over time:
- Age at exposure – Fluoride incorporated during tooth development in children is most securely retained.
- Concentration – Higher fluoride concentrations lead to more fluoride retention.
- Duration of exposure – Longer exposures means more time for fluoride to be incorporated.
- Type of exposure – Fluoridated water provides constant low doses, while toothpaste provides brief high doses.
- Individual variation – Some people’s enamel incorporates more fluoride than others.
Protecting fluoride levels in teeth
To keep as much fluoride in your teeth as possible:
- Drink fluoridated water and use fluoride toothpaste – This provides regular fluoride exposure.
- Limit acidic drinks – Acids can draw fluoride out of enamel over time.
- Get dental cleanings – Prevent plaque buildup and enamel breakdown.
- Use fluoride mouthwash – Adds extra topical fluoride.
- Receive fluoride treatments – Helps replace fluoride lost during cleanings.
Conclusion
In summary, fluoride forms an integral part of tooth enamel and is not easily removed under typical conditions. Only breaking down the enamel itself releases fluoride from teeth. Drinking fluoridated water, using fluoride toothpaste, and getting regular dental care will help ensure you maintain optimal fluoride levels in your teeth for lifelong protection against cavities and decay.