Operative dentistry and the abuse of dental hard tissues: confocal microscopical imaging of cutting.

We reviewed studies wherein the cutting of dental tissues, simulating interactions that would occur under clinical circumstances in the mouth, have been observed directly-first by real time, video rate, stereoscopic, three-dimensional scanning electron microscopy; and second and more conveniently, by video rate confocal optical microscopy. We have observed, directly, both the interactions of slow-moving cutting instruments emulating "chisels" and high-speed events, including the effects of rotary burs and air-propelled abrasive particles and soft powder slurries. The observational data contribute to our basic understanding of the functional behavior of dental tissues and formed a useful background for the practitioner of operative dentistry.