Fluoride is a mineral that occurs naturally in some foods, and that is added to most public water sources. It is beneficial for dental health because, when it gets absorbed into the teeth enamel, it can strengthen teeth, increasing their resistance to decay-causing acids. Fluoride can be ingested or applied topically. For those who do not get enough fluoride in their diet, as well as those who want an extra level of protection for their teeth, fluoride varnish is a very effective treatment.
Tooth decay occurs when plaque, the sticky film that forms on the teeth surfaces, builds up over time. Bacteria live in the plaque and, when it’s not cleaned away with daily oral hygiene habits, can create acids that soften tooth enamel in a process called demineralization. Over time, this can cause cavities to form. The minerals contained in saliva are eventually redeposited into the tooth enamel in a process called remineralization, helping to re-harden it. Fluoride helps with this process.
When fluoride is absorbed by the teeth after being applied topically, it helps to harden the enamel. It also makes it harder for decay-causing bacteria to adhere to teeth while making it easier for it to be washed away by saliva or brushed away. Fluoridated toothpaste can provide these effects, but professional applications provide a much stronger degree of protection. Applications of fluoride are especially helpful for those who are more prone to developing cavities, such as children.
To have fluoride applied, teeth will first be cleaned, then dried. The varnish is painted onto the teeth and quickly dries. It leaves a yellow film over the teeth and should be left for several hours or even overnight so that it can penetrate the tooth enamel, slowly releasing fluoride. The teeth can still be used as normal (for eating and drinking) and brushed to remove the varnish.
Fluoride varnishes can be applied with each dental appointment or once a year, depending on your personal risk for tooth decay, which your dentist will determine during regular examinations.