Ask an Expert – Flouride

Question: What is fluoride and how can it help protect my teeth from decay?

Dr. Rouble Rana, Pediatric Dentist, gives her answer…

Fluoride is a compound that contains a natural element fluorine. Fluoride containing compounds used on routine basis have been used for preventing cavities. Fluoride is sometimes added to water or in products associated with oral hygiene like toothpaste or mouthwashes. Fluoridation of water has been known to reduce cavity by 50% and is considered by the U.S. Centers for Disease Control and Prevention as “one of the 10 great public health achievement of the 20th century”. In some countries it is added to table salt instead to achieve a similar effect. The World Health Organization has endorsed the use of fluoride because of its effect on tooth decay.

Fluoride is available in two forms for dental use: topical and systemic. Topical fluorides such as fluoride toothpaste, mouthwash, gels and varnish that are applied to teeth already erupted in mouth to make them decay-resistant. Systemic fluorides are those that are ingested (fluoride added to water, milk and salt) into the body and then absorbed by developing teeth to make them decay resistant.

Fluoride prevents cavities in many ways:

  • Strengthens the enamel: Fluoride attaches to the calcium in a developing tooth to strengthen the enamel and make it resistant to decay, while in erupted teeth it hardens the enamel.
  • Demineralization and remineralization of teeth: Fluoride inhibits the loss of minerals from teeth and also encourages deposition of calcium and phosphorus to keep the tooth hard, known as remineralization.
  • Affects on bacteria: Fluoride affects the life cycle of bacteria that causes cavities.

Studies conducted over last 25 years have found fluoride to be safe and effective in dental caries (cavity) control. Too much fluoride can cause fluorosis of developing teeth. If too much fluoride is consumed by a young child (< 5 years) it may lead to fluorosis. Fluorosis is more of a cosmetic problem than an actual dental disease. It usually is mild and causes tiny white specks or streaks on teeth, which are often unnoticeable. In severe cases it leads to pitting and brown stains on teeth.

Fluoride containing products should be kept out of reach of children. Parents should dispense the toothpaste to avoid excess use. Use only a smear of fluoride tooth paste in children less than 4 years and a small pea size in children 4-6 years of age. Encourage children to spit the paste after brushing.

The American Association of Pediatric Dentistry and the European Association of Pediatric Dentistry recommend the use of fluoride toothpaste for basic caries prevention. Brushing twice a day – after breakfast in the morning and before bed at night – with fluoride toothpaste is recommended for everyone.

There are many factors to be considered before recommending fluoride tablets, lozenges, or drops. A child’s age, dental caries history, dietary habits, water fluoridation and dietary fluoride should be considered before a supplement is prescribed. Your dentist can help you recommend the right amount and source of fluoride after a thorough evaluation of these factors. Care is taken to ensure the balance is maintained between maximizing the protective effect against the dental caries and minimizing the effects of dental fluorosis.

Regular dental checks are recommended for all – first check when the first tooth erupts or before first birthday – twice a year. During these visits your dentist may apply topical fluoride on your child’s teeth. These come in different forms including gels or foams applied on teeth in a tray or varnish that is brushed or painted on teeth.


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