Should I use topical fluoride if it is already in the water?

Chances are good that you'd benefit from getting both systemic fluoride (the kind in drinking water) and topical fluoride (the kind in toothpastes, mouthwashes and professional fluoride treatments) because topical and systemic fluoride tackle the problem of tooth decay in different ways.

Let's start with systemic fluoride in its most common form -- fluoridated water. If a child whose permanent teeth are still forming drinks fluoridated water, the fluoride will make it into her bloodstream and eventually be incorporated into the teeth. It becomes part of the enamel and provides life-long protection from the inside out. That can only happen while the teeth are developing, though -- once they've popped through the gums, they're fully "cooked." But even after that, fluoride from drinking water can help because it becomes part of your saliva, which gives your teeth a constant protective bath.

What about topical fluoride? If you brush with fluoride toothpaste, use a fluoride rinse or get a fluoride treatment at the dentist's office, a little bit of the fluoride will be absorbed by the enamel, reducing the risk for cavities.

Follow your dentist's directions for using topical fluoride to maximize your defense against tooth decay. Fluoride has been responsible for a precipitous drop in the number of cavities, so you should take advantage of it!

Topical fluoride is safe to use, unless there is more than 0.7 parts per million of fluoride in your drinking water. The water department in your community will know the concentration of fluoride in your water. If you are using a prescription strength fluoride toothpaste, tell your dentist there is fluoride in your water. Also, mention any other products you use that contain fluoride.

You can feel comfortable using a topical fluoride if the mineral is already added to your water supply, since topical fluoride isn’t meant to be swallowed. (It’s worth remembering, too, that if you use a water filter, it may remove fluoride from your water.) The American Dental Association recommends that children age 2 and older, as well as adults, use a toothpaste containing fluoride. You may also want to use a fluoridated mouth rinse once a day for additional protection.

With adult guidance, kids can usually be trusted to spit toothpaste, not swallow it, after the age of 6 years. Use only a pea-sized amount of fluoridated toothpaste for children ages 2 to 5; for children under age 2, use only a smear of toothpaste or none at all. Supervise your children while they brush their teeth to make sure they don’t swallow. Fluoride mouth rinses are not suggested until age 6 or older; they require adult supervision too. Getting too much fluoride before the age of 8, while permanent teeth are developing, can leave teeth with white spots, pits and brown stains.