SELECTIVE CARIES REMOVAL WITH AIR ABRASION

The purpose of this study was to evaluate selective caries removal usi ng an air-abrasive technique. Alumina powders, glass beads, crushed gl ass powders, and crushed powders of polycarbonate resin were applied t o intact human enamel, dentin, and artificially demineralized dentin ( caries-model dentin). Furthermore, the effect of the particle size of abrasives and air pressures on the abraded depths was examined. When a lumina powders and glass beads were used, the abraded depths of enamel , dentin, and caries model increased as the particle size and air pres sure increased. Alumina powders and crushed glass powders abraded inta ct enamel and dentin more than the caries-model dentin, whereas glass beads abraded the caries-model dentin more than the intact enamel and dentin. Only crushed powders of polycarbonate resin abraded the caries -model dentin without reducing intact enamel and dentin. With hard par ticles, such as alumina powders, glass beads, or crushed glass powders , selective caries removal by the air-abrasive technique appeared to b e difficult to achieve,even if the particle size and the air pressure were changed. Crushed powders of polycarbonate resin that reduced only the caries-model dentin are harder than caries-model dentin, but soft er than intact enamel and dentin. This study elucidated the possibilit y of selective carious dentin removal with the air-abrasive technique.