Fluoride and Water

from kidshealth

Keeping kids' teeth healthy requires more than just daily brushing. During a routine well-child exam, you may be surprised to find the doctor examining your child's teeth and asking you about your water supply. That's because fluoride, a substance that's found naturally in water, plays an important role in healthy tooth development and cavity prevention.

What Is Fluoride?

Fluoride exists naturally in water sources and is derived from fluorine, the thirteenth most common element in the Earth's crust. It is well known that fluoride helps prevent and even reverse the early stages of tooth decay.

Tooth decay occurs when plaque — that sticky film of bacteria that accumulates on your teeth — breaks down sugars in food. The bacteria produce damaging acids that dissolve the hard enamel surfaces of teeth. If the damage is not stopped or treated, the bacteria can penetrate through the enamel causing tooth decay (also called cavities or caries). Cavities weaken teeth and can lead to pain, tooth loss, or even widespread infection in the most severe cases.

Fluoride combats tooth decay in two ways. It is incorporated into the structure of developing teeth when it is ingested and also works when it comes in contact with the surface of the teeth. Fluoride prevents the acid produced by the bacteria in plaque from dissolving, or demineralizing, tooth enamel, the hard and shiny substance that protects the teeth. Fluoride also allows teeth damaged by acid to repair, or remineralize, themselves. Fluoride cannot repair cavities, but it can reverse low levels of tooth decay and thus prevent new cavities from forming.

Despite the good news about dental health, tooth decay remains one of the most common diseases of childhood. According to the Centers for Disease Control and Prevention (CDC), more than one quarter of 2- to 5-year-olds and half of kids 12 to 15 years old have one or more cavities, and tooth decay has affected two thirds of 16- to 19-year-olds.

Fluoride and the Water Supply

For over 60 years, water fluoridation has proved to be a safe and cost-effective way to reduce dental caries. Today, water fluoridation is estimated to reduce tooth decay by 20-40%. As of 2002, the CDC statistics show that almost 60% of the U.S. population receives fluoridated water through the taps in their homes. Some communities have naturally occurring fluoride in their water; others add it at water-processing plants.

Your child's doctor or dentist may know whether local water supplies contain optimal levels of fluoride, between 0.7 and 1.2 ppm (parts fluoride per million parts of water). If your water comes from a public system, you could also call your local water authority or public health department, or check online at the Environmental Protection Agency's (EPA) database of local water safety reports. If you use well water or water from a private source, fluoride levels should be checked by a laboratory or public health department.

Some parents purchase bottled water for their children to drink instead of tap water. Most bottled waters lack fluoride, but fluoridated bottled water is now available. If fluoride is added, the manufacturer is required to list the amount. If fluoride concentration is greater than 0.6 ppm up to 1.0 ppm, you might see the health claim "Drinking fluoridated water may reduce the risk of tooth decay" on the label.

The Controversy Over Fluoride

Opponents of water fluoridation have questioned its safety and effectiveness; however, there has been little evidence to support these claims.

Scientific research continues to support the benefits of fluoride when it comes to prevention of tooth decay and its safety at current recommended levels of 0.7 to 1.2 ppm. Dramatic reductions in tooth decay in the past 30 years is attributed to fluoridation of the water supply, and parents and health professionals should continue to ensure that kids receive enough fluoride to prevent cavities.

The American Dental Association (ADA), the United States Public Health Service (USPHS), the American Academy of Pediatric (AAP), and the World Health Organization (WHO), among many other national and international organizations, endorse community water fluoridation. The CDC recognized fluoridation of water as one of the 10 greatest public health achievements of the 20th century.

Kids' Fluoride Needs

So how much fluoride do kids need? In general, kids under the age of 6 months do not need fluoride supplements. Your child's 6-month checkup offers a great chance to discuss fluoride supplementation with a health professional. If you live in a nonfluoridated area, your doctor or dentist may prescribe fluoride drops, tablets, or vitamins after your baby is 6 months old.

The AAP recommends that these fluoride supplements be given daily to kids between the ages of 6 months and 16 years. The dosage depends on how much fluoride naturally occurs in the water and the child's age. Only kids living in nonfluoridated areas or those who drink only nonfluoridated bottled water should receive supplements.

What about toothpastes, mouth rinses, and other products that contain fluoride? Here are a few tips:

• Kids under 2 years old should not use fluoride toothpaste unless instructed by a dentist or health professional.
• Kids younger than 6 may swallow too much toothpaste while brushing, so should be supervised when brushing and taught to spit, not swallow, toothpaste.
• Kids over age 2 should use a fluoride-containing toothpaste that carries the ADA's seal of acceptance.
• Kids should use only a pea-sized amount of toothpaste.
• Kids under age 6 should never use fluoride-containing mouth rinses. However, older kids at high risk for tooth decay may benefit from using them. Your dentist can talk with you about risk factors such as a family history of dental disease, recent periodontal surgery or disease, or a physical impediment to brushing regularly and thoroughly.

Your family dentist or pediatric dentist (one who specializes in the care of children's teeth) is a great resource for information about dental care and fluoride needs. A dentist can help you understand more about how fluoride affects the teeth, and once all of your child's primary teeth have come in, may recommend regular topical fluoride during routine dental visits.

Overexposure to Fluoride

If some fluoride is good, why isn't more fluoride better? As with most medications, including vitamins and mineral supplements, too much can be harmful. Most kids get the right amount of fluoride through a combination of fluoridated toothpaste and fluoridated water or supplements.

Too much fluoride before 8 years of age, a time when teeth are developing, can cause enamel fluorosis, a discoloration or mottling of the permanent teeth For most, the changes are subtle. In one study, 94% of identified fluorosis cases were very mild to mild. Most cases are due to inappropriate use of fluoride-containing dental products, including toothpaste and mouth rinses. Sometimes kids take daily fluoride supplements but may be getting adequate fluoride from other sources, which also puts them at risk.

Recently, the National Research Council found naturally occurring fluoride levels exceeded the optimal levels used in community fluoridation programs (0.7 t0 1.2 ppm), putting kids under 8 years old at risk for severe enamel fluorosis. The CDC recommends that in communities where fluoride levels are greater than 2 ppm, parents should provide kids with water from other sources.

The ADA also recognizes that infants need less fluoride than older kids and adults. Some infants may be getting too much fluoride in the water used to reconstitute infant formula. If you're concerned that your infant may be getting too much fluoride, talk with your doctor or dentist, who may recommend ready-to-feed formula or formula reconstituted with fluoride-free or low-fluoride water.

Very rarely, fluoride toxicity can occur when large amounts of fluoride are ingested during a short period of time. Kids under age 6 account for more than 80% of reports of suspected overingestion. Although outcomes are generally not serious, fluoride toxicity sends several hundred children to emergency rooms each year.

Symptoms of fluoride toxicity may include nausea, diarrhea, vomiting, abdominal pain, increased salivation, or increased thirst. Symptoms begin 30 minutes after ingestion and can last up to 24 hours. If you suspect your child may have eaten a substantial amount of a fluoridated product or supplement, call the poison control center or 911.

Be sure to keep toothpaste, supplements, mouth rinses, and other fluoride-containing products out of children's reach or in a locked cabinet. You should also supervise your young child's toothbrushing sessions to prevent swallowing of toothpaste or other fluoridated products.

If you have any questions about your water's fluoride content, the fluoridated products your child uses, or whether your child is receiving too much or too little fluoride, talk to your doctor or dentist.

21st-Century Dentistry

By Matthew Shulman, U.S. News & World Report

U.S. News

Kevin Ireland had his gums fixed twice a few years ago. His first treatment involved peeling back his lower gums with a scalpel to excise bacteria and stitching him up, an uncomfortable and painful experience for the 50-year-old manager of a Utah dinosaur park. While his gums were healing, his periodontist received training in a new laser technology that targets diseased gum tissues without harming healthy ones. So the treatment of his upper gums a few weeks later was virtually pain free.

Such high-tech advances are transforming how patients experience oral care, in some cases shortening their time in the chair and in recovery. Less-invasive implants, digital imaging, and new uses of lasers are also removing some of the anxiety and discomfort often associated with dentistry.

It can be easy to get caught up in the "gee whiz" factor of dazzling new technology, though, and dentists sometimes offer procedures that are neither essential nor cost effective. So each patient should develop a solid, trusting relationship with a dentist, says Gene Antenucci, a spokesman for the Academy of General Dentistry, especially before shelling out for unfamiliar treatments. "It's also important for the patient to ask questions and to do some outside research," he adds, when a dentist recommends a costly service.

Ireland's periodontist was one of a number who have begun laying aside scalpels in favor of the laser-assisted new attachment procedure, or LANAP, a novel treatment for infected gums that the Food and Drug Administration approved in 2004. The pulsing laser can distinguish by color between healthy and diseased gums and zaps away only bacteria and infected tissue, which has a darker pigment than the surrounding healthy gums.

LANAP helps connective tissue and bone form between the gums and teeth, according to a study in the December issue of the International Journal of Periodontics and Restora-tive Dentistry. "There were also signs of a regeneration of diseased root surfaces in all LANAP-treated teeth," says Raymond Yukna, the study's lead author and director of advanced periodontal therapies at the University of Colorado School of Dental Medicine. In theory, that means there is less chance of the infection returning.

The laser's heat also seals the gums with a "thermal blood clot, creating a physical barrier to any bacteria or tissue that could re-create gum pockets," says Sam Low, an associate dean of the University of Florida College of Dentistry and vice president of the American Academy of Periodontology.

Still, LANAP is unlikely to fully replace traditional gum surgery anytime soon. The laser therapy isn't demonstrably superior to surgery, reseachers recently reported in the Journal of Periodontology. Insurance will typically cover either procedure, so patients won't necessarily pay more for LANAP.

Lasers are also taking part in cosmetic treatments. Laser gum revision, for example, can reshape the gum lines in much the same way periodontists have traditionally done with a scalpel. So, patients with a gummy smile or long- or short-looking teeth can achieve a more proportioned look, says Joseph Zelig, a New York City-based cosmetic periodontist. "Think of the gums as a frame around a painting," he says. "If the frame is broken, the painting won't look good no matter how expensive it is." The laser cauterizes the gum tissue, minimizing pain and bleeding and shortening recovery.

Mini-implants

Lasers aren't the only game in town. Advances in miniature dental implants are making the replacement of decayed or missing teeth with dentures more palatable. "Mini-implants are designed for patients with limited bone in their jaws who have trouble holding in their dentures," says Antenucci. In contrast to conventional implants, which must be anchored in the jaw and take several months to fuse with bone, titanium mini-implants can be inserted in a single visit and don't require cutting the gums. And while conventional implants cost $1,250 to $3,000 per tooth, mini-implants can be just half that. Neither is typically covered by insurance.

Digital impressions

Digital impression technology, another recent advance, is taking the goo out of dentistry. Crowns, bridges, and other restorative prosthetics require an impression of a patient's teeth in order to fit correctly. This usually involves a paste or putty that takes several minutes to set. But a "virtual" impression removes the discomfort from that wait. In the new process, a digital camera scans a portion of the mouth and creates a 3-D image that precisely reflects the size and position of each tooth. Dentists with certain equipment can then produce a custom-tailored prosthetic on the spot. Others send the image to an off-site manufacturing facility, an approach that may take a couple of weeks but offers patients a wider selection of materials, like gold and porcelain. Some dentists may build the cost of the equipment and processing into the price of the restoration, making the work more expensive than conventional restoration work, which remains most dentists' only offering.

When Martha Zeeman, 40, of Lake Forest, Ill., got fitted for a crown four years ago, she could barely tolerate the impression paste because of her strong gag reflex. So when she needed three crowns last fall, she became one of the first patients to receive a virtual impression using the recently approved iTero system. "There was no more unpleasant taste and definitely no more gagging," she says.