Is Fluoride Safe For Teeth?

by | Sep 12, 2020 | Adult Teeth


Fluoride is one of the most talked-about minerals in dentistry. In patients, it evokes either fear of harm or gratitude for its positive effects on oral health. All of this is caused by the lack of awareness about fluoride products by the general public. In this article, we will discuss if fluoride is safe for teeth and its mechanisms of action. 

Mechanism of action

Teeth are made up of hydroxyapatite crystals which are composed of calcium and phosphate minerals. On daily basis, teeth undergo demineralization and remineralization processes where they lose and gain minerals respectively. When teeth lose minerals, their structure weakens and when they gain minerals, their structure strengthens. For example, acidic drinks cause the teeth to lose minerals such as calcium and phosphate thus, weakening the tooth structure. However, when you use products containing fluoride such as water, toothpaste or mouthrinse, the fluoride helps to rebuild the crystalline structure of the tooth by becoming incorporated into the crystalline structure. Tooth structure containing fluoride is known as fluorapatite. Fluoroapatite is significantly stronger and resists external damage much better than just hydroxyapatite crystalline structure.

Demineralization and remineralization occur through the process of diffusion of minerals in and out of enamel. That is why fluoride needs to be in direct contact with the tooth in order to produce the best results. By direct contact I mean that fluoride should either be directly applied onto the tooth surface or swished around the mouth in order to coat the tooth surface. Fluoride tablets that increase systemic fluoride levels are not as effective at remineralizing teeth comparing to topical products.

Methods of fluoride delivery

Fluoride can be either naturally occurring, found in community based products, home based products or professional dental products.

Fluoride naturally occurs in food and water. Here is a list of top foods and drinks that contain fluoride: shelfish, potatoes, grapes, artificial sweeteners, flavored popsicles, baby foods, broths, stews, tea, coffee, and sodas. Groundwater can also contain various concentrations of fluoride depending on its geographic area.

The government deliberately adds fluoride to communal water, salt and milk in order to fight dental decay. These methods of delivery allow for a large population of people to get passive protection from dental decay. For the government, it is also much more cost-effective to “prevent” dental decay rather than to “treat” it. Numerous studies have shown the efficacy of fluoride water in reducing dental decay. That is why communal water fluoridation is considered to be one of the greatest 10 public health achievements of the 20th century by the Centers for Disease Control and Prevention. To read more about communal water fluoridation please click here.

You can also find fluoride in toothpastes, and mouthrinses. These are two easy ways of delivering fluoride to your teeth as part of your every day oral hygiene routine.

Lastly, professional fluoride products such as fluoride varnishes and gels can be found at your local dental office. These products have a really high concentration of fluoride that you will not be able to find in your home-based products. Professional fluoride products are very effective at remineralizing your teeth. However, because of their high concentration, you should only have them applied to your teeth by a trained dental professional.

Benefits of fluoride

There are four main benefits of fluoride. First, fluoride helps to rebuild or remineralize weakened tooth enamel. Second, it helps to slow down the loss of minerals from tooth enamel. Third, it has the capability of reversing early signs of tooth decay before it had the chance of forming a cavity. Lastly, it helps to inhibit bacterial growth and plaque formation on the tooth surface.

Is fluoride safe for teeth or toxic?

The downside of fluoride is that it can cause dental fluorosis. Dental fluorosis is characterized by the pitting and mottling of teeth which is not very aesthetically pleasing to most patients. Having said that, please keep in mind that fluorosis DOES NOT occur unless an EXCESSIVE amount of fluoride is consumed. Remember that anything in excess can be bad for you. For example, you can get high blood pressure from too much salt, diabetes from too much sugar, and drunk from too much alcohol. So moderation is “key” to successful fluoride treatment.

Is fluoride safe for teeth at these product concentrations?

Children under 12 years old are at the highest risk of dental fluorosis because their teeth are constantly undergoing development. That is why parents of children under 12 years old should monitor their child’s fluoride intake. Below are the safe fluoride concentrations for children under 12 years old. For example, if your child is under 18 months old then you should use toothpaste without fluoride. While for children between 18 months and 6 years you should use toothpaste with a reduced amount of fluoride concentration (500-550ppm). Whereas for children above 6 years old you can allow them to use adult toothpaste that contains fluoride at a concentration of 1000-1500ppm. In case of severe decay and demineralization, your dentist may prescribe you a 5000ppm toothpaste. 

As a side note, be careful not to use Tooth Mousse Plus and mouthrinses containing fluoride on children under the age of 6 years old.

Professional fluoride products

In the dental office, you should not worry about using professional fluoride products due to their high fluoride concentration. Because in the dental office, the dentist will take all the necessary precautions to prevent fluorosis. The dentist will also know how to handle emergencies in case you accidentally ingest the concentrated fluoride product.

After a professional dental clean, you should use a topical fluoride product to help remineralize and strengthen your teeth. You have a choice between a fluoride varnish and a fluoride gel as both can be used for remineralization of teeth. If you chose to go with fluoride varnish, the dentist will spread it on the teeth using a little brush then, the varnish will stay on your teeth for at least 4 hours as it slowly releases fluoride. If on the other hand, you chose to go with fluoride gel, then the dentist will load it onto a special tray that you keep in your mouth for 4 minutes before it gets aspirated. Both products are excellent at remineralizing teeth. However, fluoride varnish is safe for children under 10 years old whereas fluoride gel is not due to the high risk of ingestion.


In conclusion, is fluoride safe for teeth? Yes, fluoride is completely safe for teeth at low concentrations. In fact, I would recommend combining community-based fluoridated water with fluoridated toothpaste and mouthrinse for the most protection against decay. Having said that, always make sure that the fluoridated products used correspond to the age of the person using them by reading the label.

Please click the following links if you would like to learn more about the meaning/use of the ingredients inside your toothpaste and about the foods that are bad for your teeth.

Hi, I’m Yana!

I’m a fourth year dentistry student and I’m here to share with you:

  • how to take care of your and your little one’s oral health
  • good dental practices for prevention of disease
  • facts on teeth whitening and cosmetic dentistry
  • answer any lingering questions
  • and MORE!

Stay Tuned!

“Be joyful in hope, patient in affliction, faithful in prayer.” Romans 12:12

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