A new saliva test could help kids beat cavities before tooth trouble even starts.

The Caries Assessment and Risk Evaluation (CARE) test predicts which kids are most at risk for tooth decay and reveals which teeth are vulnerable to cavities, say the test’s developers.

The CARE test was created by University of Southern California (USC) School of Dentistry professor Paul Denny and colleagues.

“When we apply this to young children, it allows us to predict what might be their future [cavity] history — the number of cavities that they’ll get by, say, their late 20s or early 30s,” says Denny, in a news release.

Cavities are the result of tooth decay. The problem starts when foods containing sugars or starches are left on the teeth. Bacteria living in the mouth digest those foods, turning them into acids. Plaque — a sticky film of bacteria — helps keep these acids in contact with teeth. The acids dissolve tooth enamel, forming cavities.

Fillings close up cavities, but they don’t last forever. Later, many patients need route canal or crowns, which are more costly and extensive fixes. In the worst-case scenario, cavities can lead to tooth loss.

How the Test Works

The CARE test searches saliva for sugar complexes. Those sugar complexes aren’t all bad. Some help prevent cavities by repelling cavity-causing bacteria. Others make tooth decay more likely by letting bacteria latch on to teeth to do their destructive work.

A person’s proportion of “good” or “bad” sugar complexes indicates his cavity risk and is determined by genetics, say the researchers.

The CARE test has a four-level ranking system to predict future cavities.

The test has been tried on 29 children aged 7-10 years. Results were presented in Washington, D.C. at the annual meeting of the American Association for the Advancement of Science.

The researchers also want to try the test on infant saliva, gauging babies’ cavity risk long before they cut their first teeth. They also plan long-term studies of the CARE test’s accuracy.

If successful, the saliva cavity test could help tailor dental care to each child.

“It’s possible that in the future — even though a kid might be at very high risk for getting a large number of [cavities] — with the proper preventive measures he [or she] can arrive at adulthood without any,” says Denny, in a news release.

Cavity-Fighting Tips

Good (or bad) oral hygiene and nutrition can change dental health. It’s important to take care of teeth and eat healthfully, but that may not solve all tooth problems. Overzealous brushing can wear down tooth enamel, and completely eliminating sugar from kids’ diets has not been shown to totally prevent cavities, says the news release.

The CARE test could also help families that can’t afford regular dental checkups, say the researchers, suggesting that school nurses may one day administer the test.

But that would just be the first step in avoiding cavities. The CARE test only predicts cavities. Prevention would still require proper dental care.

To help prevent cavities, try these tactics:

—Brush your teeth at least twice daily. Preferably, brush after each meal and before bedtime with a toothpaste containing fluoride. The American Dental Association suggests brushing with an ADA-accepted fluoride toothpaste.

—Clean between your teeth daily. Use dental floss or interdental cleaners. Since cavity-causing bacteria and food particles remain in between teeth, flossing can help remove this.

—Eat a healthy, balanced diet. If you indulge in starchy, sugary, or sticky foods, brush afterwards.

—Consult your dentist. Get regular cleanings and checkups, and ask for other cavity-prevention tips.

By Miranda Hitti, reviewed by Brunilda Nazario, MD

SOURCES: American Association for the Advancement of Science Annual Meeting, Washington, D.C. Feb. 17-21, 2005. WebMD Medical Reference in collaboration with The Cleveland Clinic: “Cavities.” News release, University of Southern California School of Dentistry. WebMD Medical News in collaboration with The Cleveland Clinic: “Preventing Tooth Decay and Cavities.” American Dental Association.