Dental More Gentle with Painless 'Drillings' and Matching Fillings

by Food and Drug Administration (FDA)

Kids today have it so good — computers in the classroom, Nickelodeon on cable TV, popcorn in the microwave. They also have it good because they rarely get dental cavities. And, for those who do develop tooth decay, newer dental devices the Food and Drug Administration has cleared in the past two to five years are less painful than the traditional dentist's drill.

Public health measures, such as fluoridation of drinking water and consumer education on proper dental hygiene, have helped bring about a decline in cavities in the past 50 years. Today, half of all American children under 12 have never had a cavity. For adults, these preventive measures, along with new filling materials, are enabling many of them to keep their own teeth for the rest of their lives.

"There's really no reason in this country today that [people] can't maintain their own teeth for their entire life," says Kimberly Harms, D.D.S., a dentist in Farmington, Minn.

Digging Out the Decay

The only way to treat tooth decay, technically known as dental caries, is by cutting away the decaying portion of the tooth, a procedure that is done almost 170 million times a year. Until about five years ago, the only way to do that was with the standard handpiece, commonly known as the dental drill, a device that dates to the 1700s. Modern high-speed handpieces revolutionized dentistry when they were introduced in the 1960s.

Today, dentists have two other options — the erbium:YAG laser and the microair abrasion unit. FDA cleared the erbium:YAG laser for marketing for use on adults in May 1997 and for use on children in October 1998. Though the clearances were the first of their kind for treating "hard-tissue" in the mouth, the laser actually was introduced into dentistry in 1995, when FDA cleared a laser device for gum surgery.

As of March 1999, two companies market the laser for dental decay: Premier Laser Systems Inc., of Irvine, Calif., and BioLase, of San Clemente, Calif.

The erbium:YAG laser essentially vaporizes decayed tooth tissue. A stream of laser light that passes through a fiber connected to a pencil-like handpiece is directed to the decay. The laser handpiece looks like the standard handpiece and, like the standard handpiece, must be used in a controlled manner so that it doesn't slip and damage healthy tissue.

"The laser is a cutting instrument," says Susan Runner, D.D.S., branch chief of dental devices in FDA's Center for Devices and Radiological Health. "And like any cutting instrument, dentists have to be careful any time they use it. The laser has many of the same risks as the drill."

Another similarity between the dental drill and the laser is that both use water and air to cool the tooth and clean the surface during removal of decay. While dentists and patients may wear eye protection during conventional treatment to protect against the spray of water and particles, they must wear goggles during the laser procedure to protect their eyes from straying laser light.

The laser has several benefits over the handpiece: Because laser treatment is usually painless, there is no need for anesthesia — or anesthetic injections — in many patients, and dentists do not have to wait until their patients' mouths are numb to begin treatment. Also, the laser eliminates the vibrating sensations of the high-speed handpiece.

Also, compared with the standard handpiece, the laser can work with better precision, saving more of the healthy tooth. And when the laser procedure is done, patients do not have to wait for the numbness and puffiness related to the use of anesthesia to fade.

For many patients, especially those particularly fearful of the dental drill, the laser has drawn rave reviews. "My patients love it," says Edward Romano, a dentist in Morristown, N.J., who has used the laser since 1997. "They say: 'I can't believe it's so comfortable, that dentistry has come this far.'"

However, the laser is not without its own shortcomings. For one, it can't be used on teeth with fillings already in place. According to Runner, there is the risk of damage to the tooth because the filling heats up. Romano says silver fillings also damage the laser tip. Also, studies show that the laser procedure takes longer than the conventional method.

"The laser is really ideal for virgin teeth — for new decay," Runner says. "Dental lasers is a growing field, but they can't do everything. There's still a need for the standard handpiece."

Another potential pitfall is expense. In December, Premier Laser Systems was citing a list price of about $45,000 for its Centauri laser. That includes training for the dentist. The standard high-speed handpiece typically sells for around $600.

Premier Laser estimates, however, that while the typical laser procedure costs about $13 more on average than the same drill procedure, the cost reductions of not using anesthesia and having more time to spend with other patients could actually save dentists about $70,000 over three years.

Still, some dentists say they are putting off buying a laser for treating cavities, at least for the near future. "Our position [in my dental practice] is that the laser looks promising," Harms says. "But we're not using it yet. We're waiting for long-term studies and newer tools."

The other alternative to the traditional high-speed handpiece is the air abrasion handpiece. Air abrasion involves the use of a high-pressured instrument similar to a tiny sandblaster. A stream of tiny aluminum oxide particles cuts away the decay. There is no heat and no vibration, and often, it can be used without anesthesia. It also can be used to remove some fillings, although it is not yet cleared for removing amalgams (silver-colored fillings).

Harms, who uses air abrasion, says the technique is ideal for small cavities and fillings in children, but she notes, "It doesn't replace the drill."

About the Author

www.fda.gov
FDA is A United States government body that oversees medical devices, including contact lenses, intraocular lenses, excimer lasers and eyedrops. In the US, these products must be approved by the FDA before they can be marketed.