The UV wavelengths used give an efficient drilling process, generating almost no heat. Also UV light can be brought to a sharp focus making it possible to drill shapes of very high precision. Just a few seconds of laser action can cut a perfect pyramid into the tooth, only one fifth of a millimetre across, with no damage to the surrounding tissue. A close up of the laser-drilled surface shows how cleanly the laser cuts through the minute tubes which form the dentine part of the tooth. This level of accuracy could also pave the way to keyhole dentistry.
Current techniques remove a large portion of the tooth to get at inner decay.
This weakens the tooth considerably, especially if the biting surface is removed. Using lasers, a very small hole could be used to tunnel down to the decay in the tooth, leaving the bulk of the tooth undamaged and much stronger. This leaves an entrance to the inner tooth through which decay causing bacteria can pass. Laser drilling coupled with new ceramic materials could lead to longer lasting and stronger fillings. A filling will also adhere to the clean laser-cut surface better than to a rough abraded surface.