Blasting Decay Away : New dental instrument that uses particles and compressed air to prepare tooth for filling is said to be easier to take than a drill.

What’s more unnerving than chalk screeching across a blackboard? For millions of people, it’s the dreaded grinding sound of the dental drill.

Now there’s a new instrument, the KCP 2000, developed by American Dental Technologies in Troy, Mich. The KCP, which stands for kinetic cavity preparation, essentially sandblasts decay, eliminating the need for anesthesia or a drill and cutting in-the-chair time from 30 minutes to a tolerable 10 minutes.

While a drill actually grinds away tooth structure, the KCP 2000 uses compressed air to send 4.3 million particles per second of an alpha alumina compound against the decay. The KCP tends to remove less good tooth structure than a standard drill, thus possibly preventing the need for a crown later on, according to Alan Howard, an Encino-based dentist who has used the technology in his practice for almost a year.

“While the conventional drill creates vibration and heat, which tend to be felt as pain, the KCP cuts the tooth by abrasion, which doesn’t hurt,” said Howard. “All the patient feels is a sandy mouth for a minute or so.” Because the KCP doesn’t cause pain, no anesthetic is used.

The KCP--which costs about $20,000--20 times the cost of a conventional drill--works best on virgin teeth, and cannot be used when replacing an old silver filling, Howard said. So it’s terrific for most children and for adults with uncomplicated dental problems. It is also used to prepare pits and fissures in the tooth enamel before applying sealants. And because anesthesia is not needed, a dentist can treat multiple sites of decay in one visit.

“It won’t replace the drill, but can be used in 20% of the cases and with 80% of children,” Howard said.

The KCP also is effective in allowing dentists to remove early-stage cavities right away, rather than waiting six months or so until the decay becomes more receptive to drilling. “We’re more likely to sandblast at the first sign of decay--we don’t have to wait and watch--and the smaller preparations last longer,” Howard said.

The charge for KCP fillings is the same as for the conventional method, but dentists say their investment in the new technology pays off because it helps them build their practices.

Because the KCP was introduced just over a year ago, is considered expensive and has somewhat limited applications, finding a dentist with the air-abrasive technology can be challenging. Gary D’Spain, regional product consultant for the manufacturer, said only a handful of dentists in Southern California are using the KCP.

Christine Dumas, consumer adviser for the American Dental Assn. and clinical professor of dentistry at USC, warns that the KCP demands a high level of technical skill to be used effectively. “Air-abrasive technology moves quickly, so dentists have to be able to envision the shape they want ahead of time, and their hands have to be exceptionally steady,” she said.

Consumers should not choose their dentists by the high-tech resources they use in their practices, Dumas said. “It’s the relationship a patient has established with the dentist that counts,” she said.

Even if a dentist has the KCP, it cannot be used for deeper cavities or crowns, so it is important to talk with the dentist and learn how pain can be prevented in today’s dentistry, Dumas said. But for those who are confirmed dental phobics--and the American Dental Assn. estimates there are more than 35 million Americans in this category--such no-shot, no-drill devices as the KCP may induce them to give dental care another chance.

Corinna Kowalsky, 22, of Sherman Oaks, recently got a KCP treatment and filling after procrastinating for more than a year because of her fear of the injection and the conventional drill.

“I had been so scared, but you cannot feel anything. You have a really, really dry mouth, but that’s it. And you go home and you don’t even feel you have been to the dentist,” Kowalsky said.