Root surface temperatures produced during post space preparation

In vitro root surface temperatures produced during post space preparation were measured. The preparations were made using a GPX bur with rotational speeds of 6,500, 8,000, 9,500, 11,000, and 15,000 rpm. The overall mean temperature increase ranged from 0.66 degree to 4.81 degrees C and was greatest at 8,000 rpm. When speeds > 8,000 rpm were used, temperature increases also resulted, but they were significantly less than that which occurred at 8,000 rpm. Damage to the supporting structures of teeth should not occur when this bur is used, at any of the speeds evaluated, to create a post space.