Effect of Drilling Speed on Dental Implant Insertion Torque

The specific aim of this study was to examine whether slow drilling speeds (15 rpm) produce pilot holes that result in different implant insertion torques than pilot holes made with higher speed drilling (1500 rpm). To accomplish this, a new method is presented for transferring samples from a drilling machine onto an implant insertion torque measuring apparatus while maintaining the same center of rotation. Simulated bone blocks of polyurethane were used with 2 densities of foam to mimic trabecular and cortical bone. Pilot holes drilled using both drilling methods were morphologically characterized at macro and micro scales. Nobel Biocare Nobel Active implants were then placed. Profilometer and optical imaging were used to determine changes in the pilot hole morphology. Recorded insertion torque measurements were used to quantitatively contrast implants inserted into holes drilled using the 2 speeds. Although there were slight qualitative and quantitative differences between the low- and high-speed drilled pilot holes, the differences were insufficient to cause a statistically significant change in insertion torque.