New-age dentistry has abandoned the dreaded drill in favor of a laser that is making pain obsolete.

The dental laser beam is delivered in pulses that don't last long enough to trigger a pain nerve, according to an article in the current issue of Popular Mechanics, a Hearst magazine, and it is only one of the high-tech tools working toward painless den-tis-try.In the past, dentistry has been nearly synonymous with pain, and as a result 30 million to 40 million Americans ignore dental checkups - sometimes until they start losing teeth.

After years of research neglect, new systems are finally reaching dentistry. Cavities can be treated with lasers that silently vaporize tooth decay, patients have their teeth checked by an X-ray probe that instantly creates crystal-clear pictures without film, and crowns can be made by computer-controlled milling machines, eliminating the need for goo-filled biteplates.

If all this fails, unsalvageable teeth can be replaced with titanium implants that are stronger than natural teeth.

What may make dental X-ray film obsolete is a new technology called radiovisiography, developed by Dr. Francis Moyen and manufactured in France. Its high-resolution images improve the dentists' ability to make accurate diagnoses while reducing the radiation to which patients and technicians are exposed.

Once a cavity is found, there's the American Dental Laser, the first approved by the Food and Drug Administration for dental use.

Patients report experiencing less pain when being operated on with the dental laser than with drills. Part of the reason is that the laser does not cause many of the psychological components of pain. The whining noise and vibrations associated with conventional dentists' drills are ab-sent.

In addition, the laser beam is delivered in pulses that last only 30-trillionths of a second, less than the time needed to trigger a pain nerve.

If a tooth is beyond repair, an expensive but increasingly popular alternative to dentures is the titanium dental implant, a remarkably strong, naturally functioning permanent pros-thesis.

The dentist drills a hole in your jaw at the site of the missing tooth and fills it with a tight-fitting titanium cylinder. Within three to six months, the bone and gum tissue grow around the cylinder, anchoring it firmly in place.

At this point, the top of the implant is surgically exposed and an artificial tooth made of porcelain or plastic resin is bolted to the implant. This results in a false tooth that is as strong as the real thing.

Because of the high cost of implants - $1,500 to $2,000 per tooth - most people still opt for crowns and bridges, and there are 30 million crowns cast in the United States each year.

Future dental technologies now are being tested on a "motor mouth" - the dental researcher's equivalent of a crash dummy. It's a hydraulically powered artificial mouth that simulates the complex forces of human chewing. Test teeth in the artificial mouth are mounted in an environmental chamber, which is fully enclosed, and then exposed to a continuous flow of fluid as the hy-draul-ically powered artificial jaws grind away.