Santé Montréal

Preventing tooth decay with fluoride and fluoridated water

Fluoridation of drinking water

Fluoridation of drinking water is the most effective and economical way of providing the whole population with enough fluoride to prevent dental caries.

What are the effects of fluoride on teeth?

Fluoride acts on teeth at two levels:

  • When the teeth are forming, it strengthens the enamel and makes it more resistant to decay.
  • It also has a local effect when it comes directly into contact with teeth.

Thanks to these two combined effects, fluoride can significantly reduce dental caries. However, because fluoride can be ingested from several sources, it is important to control how much is consumed in order to maximize its protective effect against caries while minimizing the risk of dental fluorosis.

Fluoride-containing toothpastes

Dental caries have decreased significantly over the last 20 years, largely due to the use of fluoridated toothpaste.

Most toothpastes on the market contain an optimum dose of fluoride. They are easy to recognize because they display the logo of the Canadian Dental Association.

Using fluoride toothpaste is important, but caution must be exercised with children, who have a tendency to swallow their toothpaste up until the age of seven. Children should only use a small amount (less than the size of a pea) when brushing their teeth, and they should be taught to rinse their mouths and spit the water and toothpaste out.

Fluoride supplements  

Fluoride supplements are available in the form of lozenges, chewable pills or drops (separately or in combination with vitamins).

Before giving a fluoride supplement to your child, you should speak to your dentist and your pediatrician about the right dose. The fact that children can get fluoride from more than one source (drinking water, toothpaste, vitamins, etc.) means that there is a risk of getting too much, which can cause dental fluorosis. 

If the drinking water in your municipality is fluoridated, your children do not need to take a fluoride supplement.

Fluoride applications by the dentist

Your dentist may apply a fluoride gel on your child's teeth for a few minutes in order to strengthen the enamel. This is usually done on new teeth, which are more vulnerable to caries. Ask your dentist if this is something that should be done to protect your child's teeth. 

Fluorose dentaire (French only)

La fluorose dentaire

Lorsqu'un jeune enfant est surexposé au fluor, il peut apparaître des taches blanches sur ses dents. C'est la fluorose dentaire.

Dans la plupart des cas, la fluorose est légère et les taches sont très peu visibles. Les cas plus graves peuvent être traités par un dentiste. La fluorose dentaire ne met pas la santé en danger. C'est un problème esthétique.

Ordre des dentistes du Québec - Le fluor

Association dentaire canadienne - Le fluorure et votre enfant

Ordre des hygiénistes dentaires du Québec - Les fluorures