Flouride plays an important role in minimizing the risk of dental decay. The main way it does this is by hardening the structure of the tooth, thereby making the enamel more resistant to the acid attack from bacteria.
Flouride exposure has dramatically reduced the incidence of dental decay, so much so that we routinely see children enter adulthood having never had a cavity.
Topical fluoride treatments are often given to children at each hygiene appointment to help strengthen the teeth.
These treatments are not limited to children. Adults who have had many restorations, or oftentimes older adults with decreased salivary flow, certainly benefit from fluoride treatments as well.