TO CUT TOOTH DECAY: A LASER vs A DRILL
THE WALL STREET JOURNAL
The Ache: The dental drill is among the most hated of medical devices.
The Claim: Lasers cut away tooth decay with so little pain that anesthetic is rarely needed. And since they are precise, more of the tooth can be preserved.Biolase's Waterlase iPlus works by heating water molecules in the tooth, which expand and dislodge decay.
The Verdict: Several published studies have found lasers can often allow patients to skip numbing anesthetic when getting cavities treated. But there's scant evidence showing the lasers provide long-term benefit to teeth, as some dentists claim.
Lasers use a light beam to cut away tooth decay before filling cavities, resulting in less vibration and pain than traditional drills, says Barry Jacobson, a pediatric dentist at Mount Sinai Medical Center in New York. Dr. Jacobson has published reports saying the less-painful laser cavity prep can be used to allow even children to skip anesthetic.
Lasers vary in type, but one major brand, Waterlase, works by heating water molecules in the tooth, which then expand and dislodge decayed tooth structure, according to manufacturer Biolase Inc. BIOL +0.38% of Irvine, Calif.
Chris Walinski, clinical director of Biolase, says that the company's lasers also don't make tiny cracks in teeth called "microfractures," which can be an unwanted side effect of drilling. But the company hasn't published any long-term data showing laser procedures are better for teeth.
Alan Swett, adjunct instructor of operative dentistry at the University of Iowa, says it isn't known if avoiding microfractures "makes a difference long term."
A number of studies on lasers have shown both children and adults can have cavities filled without a numbing injection. A 2002 Japanese study of 50 cavities filled in adults found in 68% of the cases the patient felt no pain even without anesthetic; slight pain was felt in 22% of cases and tolerable pain in 4%. In 6% of the cavity preparations, patients said they felt "intolerable pain" and anesthetic was given.
Whether anesthetic is needed with a drill depends on the patient's pain tolerance and the depth of the cavity, says Robert M. Pick, Chicago dentist and spokesman for the American Dental Association.
Dr. Jacobson says the device is "good for patients" because it provides a more comfortable experience. But he adds dentists have been slow to adopt lasers in part because of the cost and in part because older models were much slower than drilling.
The newest laser models cut away tooth at about the same speed as drills, says Biolase's Dr. Walinski. The newest models are even less painful than the earlier model from the company used in the Japanese study, a company spokesman adds. Biolase says its Waterlase line of lasers is in about 5% of U.S. dentist offices.
Dentist Steven Spitz demonstrated the company's new $60,000 Waterlase iPlus, which hit the market in 2011, at his Brookline, Mass., office. The laser, which made a rapid-fire popping sound, cut cleanly and quickly through the outer shell of a hard-boiled egg. The incision was thinner and cleaner than one made with a drill. He says the laser allows him to remove less tooth material than when he uses the drill. "The less tooth structure you remove, the longer the tooth will last," says Dr. Spitz, who is occasionally paid to speak for Biolase.