Direct Measurement of Heat Produced during Drilling for Implant Site Preparation

The aim of this study was to directly measure the temperature of the drill during implant site preparation. The measured temperature was compared to that previously reported inside the bone. The temperature change of the drill was measured using a thermocouple inserted inside the stainless steel drill using an 18-gauge needle and mercury-containing slip ring. Three thermocouples were inserted into the bone with different depths of 10 mm, 5 mm and 1 mm. The thermocouple was 0.5 mm away from the periphery of the drilled hole with a diameter of 3.4 mm. The drill rotating speed varied from 500 rpm to 2000 rpm. Each drilling procedure was performed 10 times, and the average was calculated. The temperature of the drill increased rapidly, and the thermocouples in the bone reached a maximum temperature after the drill temperature started to decrease. The maximum inner temperature of the bone was the highest at a depth of 10 mm. The patterns of the temperature change were similar at different rotating speeds. The actual maximum temperature at the drill and bone interface was significantly higher than the temperature measured inside the bone in previous reports