By Nancy Volkers
InteliHealth News Service

According to the American Dental Association, 12 percent of Americans are afraid to visit the dentist. Many of them are afraid of pain from needles. But needles don't have to hurt.

Many dentists use anesthetic gels to numb an area before inserting a needle. But a relatively new tool — a patch similar to a Band-Aid that releases anesthetic as it sits on your gum — works better than the gel.

"We found that [the patch] really worked for injections. Many people didn't even feel the injection at all," said Michele P. Carr, M.A., assistant professor at Ohio State University and lead author of a study that tested the effectiveness of DentiPatch, made by Noven Pharmaceuticals, Miami, Fla.

The researchers tested the patch in three procedures:

• Needle sticks, in which a needle was inserted into the gum but no injection was given
• Needle sticks with an injection of local anesthetic
• Scaling and root planing, a deep cleaning of the teeth that requires going below the gum line

The patch and gel were compared in patients undergoing needle sticks without injection and for scaling and root planning. Also, the patch was compared with placebo (a patch containing no anesthetic) in patients undergoing needle sticks with and without an injection. In each case, the patch was more effective.

Because of the mouth's anatomy, Carr said, the patch works better on top teeth than on bottom teeth.

The researchers also noted that the needle stick with an injection of anesthetic was more painful than a needle stick alone. "It's the injection itself that hurts," Carr said. "The pain is from the pressure of the liquid going into the tissues." Pain scores were significantly higher when an injection was given, but the patch group still rated injection pain as mild, while the placebo group rated it as severe.

"Probably the best use for [the patch] is for front teeth, and if you have to get an injection in your palate," Carr said.

The patch takes more time to work than the gel does. According to the instructions, the dentist should keep the patch on for at least five minutes. The patch is also more expensive: Carr estimated the cost at $2 each.

The U.S. Food and Drug Administration approved the patch in 1996, but Carr said many people — including dentists — don't know it exists.

"I wish more patients knew about it," she said. "I'd ask [my dentist] for it."

The study was published in the December issue of the Journal of the American Dental Association.