How does fluoride help prevent tooth decay?

Fluoride is a compound that contains fluorine, a natural element. Using small amounts of fluoride on a regular basis can help prevent tooth decay. Fluoride inhibits loss of minerals from tooth enamel and encourages remineralization (strengthening areas that are weakened and beginning to develop cavities). Fluoride also affects bacteria that cause cavities, discouraging acid attacks that break down the tooth. Risk for decay is reduced even more when fluoride is combined with a healthy diet and good oral hygiene. Using fluoride for the prevention and control of decay has been proven over the past 70 years to be both safe and effective.
Fluoride can be found in any toothpaste with the ADA Seal of Approval. To ensure you’re getting the appropriate amount of fluoride, having a professionally applied fluoride treatment during your next checkup is possible if you are concerned you are not getting adequate amounts at home.

American Dental AssociationAmerican Academy Of Cosmetic Dentistry