You need a filling and you're not exactly looking forward to it. But what you dread most isn't the pain. Local anesthesia takes care of that.

What you dread is the drill.

Dentists call it a "handpiece," but we all know it as the drill. Its high-pitched whine, like a million mosquitoes on steroids, strikes fear into the heart of even the most courageous. The thought of it touching your teeth makes your muscles tense and your palms sweat.

One alternative to the drill is air abrasion; a method of cleaning out tooth decay.

One advantage of air abrasion is that you don't hear any noise or feel any vibration. Air abrasion works like a tiny sandblaster. Compressed air and an abrasive powder wear decay off your tooth.

Needle phobes also may have reason to rejoice. For shallower cavities, you may not need an anesthetic, although the air and the abrasive powder can cause some sensitivity.

The procedure is relatively simple and quick. Often, if a small cavity is found during a checkup, the dentist can fill it the same day in about 10 minutes using air abrasion.

The procedure can't be used for everything. For instance, air abrasion can't be used for deep fillings, or for veneers, crowns, inlays or onlays. Also, only composite resin fillings can be used because they will adhere to the smooth surface created by air abrasion. Silver (amalgam) fillings require accurate cuts made by the drill into the tooth. That's what prevents the amalgam filling from falling out.

An air abrasion machine consists of an air compressor and a tank of abrasive aluminum oxide particles. The particles come in two sizes: 27 microns and 50 microns. (There are 1,000 microns in a millimeter, and about 25,000 microns in an inch.) One of the reasons most dentists do not use this technique is that it generates a large amount of dust.

The compressed air and the particles come out through a nozzle and wear away the decay. Your dentist can control the size of the nozzle opening, which size particle is being used and the air pressure.

Some precautions are needed. If you receive air abrasion, your dental team will use a rubber dam or a protective resin to keep the particles from wearing down other teeth. Your dentist also may put protective resin on your gums.

You and your dental team will wear protective eyewear. The dental assistant will suction your mouth constantly to remove the particles. You may notice a funny taste in your mouth afterward from the particles.

Air abrasion is a technique that must be used carefully. The dentist can remove more of the tooth than necessary because it's difficult to "feel" the difference between healthy and decayed parts of the tooth while performing air abrasion.

The problems with inhaling the dust and maintaining infection control have limited the use of this procedure. Dentists and patients who are interested in quiet, pain-free alternatives to a regular dental drill increasingly have turned to the use of lasers.