Abstract
In tooth preparation, the heat generation by cutting may cause injury to the pulp as well as severe discomfort to the patient. In this study, in vitro measurements of the temperature changes in the pulp chamber during cutting were performed on extracted human incisors. The tooth was cut inward from its labial surface with an air-turbine handpiece under each combination of the conditions of (1) cutting load : 20, 50 and 80 g ; (2) grit size of diamond bur : coarse, regular and fine ; and (3) water spray : 0, 1 and 5 ml/min. When the cutting load was small, the temperature rise of the pulp chamber was small and the temperature rather decreased by water spray. As the cutting load increased, the temperature of the pulp chamber increased ; however, the increment varied according to the interaction of the load and the amount of water. No significant differences were found in the temperature change between the coarse and regular grit sizes of the diamond bur used, while the temperature rise was minimum with the grit size of the bur.
