Accuracy of a Manual Torque Application Device for Morse-Taper Implants: A Technical Note

Purpose: The objective of this study was to compare torques applied by new and used manual torque devices for Morse-taper implants. Material and Methods: Fifteen ITI manual torque devices were tested. Those in group 1 (n = 5) were new (ie, never used), those in group 2 (n = 5) had been used 50 to 200 times, and those in group 3 (n = 5) had been used 500 to 1,000 times. The torques applied by each device were measured for 35 Ncm and 15 Ncm targets in an experimental setup by a custom-made wrench with strain gauges connected to a data acquisition system. The strain-gauge signals were simultaneously delivered to a computer at a sample rate of 10,000 Hz and converted to torque units. Results: New devices applied higher torques than used devices for the 35-Ncm torque target (P .05). The torques applied by group 3 devices were approximately 1.5 Ncm lower than those of other groups for the 35-Ncm target and approximately 1 Ncm lower for the 15-Ncm target. Discussion and Conclusion: ITI manual torque devices deliver consistent torque output, although a slight decrease occurs as a consequence of clinical use.