[Studies on the performance of the dental air turbine handpieces. (Part 3) Torque measurements of the air turbine handpieces (author's transl)].

Air turbine handpieces, electro-micro motors and electric engines are widely used as the dental cutting instruments for the clinical use. So, this paper examined the measurement of rotational torque of the high speed dental instruments used for cutting works. For the measurement of torque of the dental instrument, we have measured the pushing load of the test but as used for cutting tools. But, in this paper, we attempted the new trials which are the measuring the tangential force of test bur rotated with the high speed velocity. And then, the kinetic energy values of rotational bur are obtained with using the value of the test bur's rotational torque. Besides we examined the interrelations of the rotational torque and pushing as the results, and both measurement value show the good relations for air turbine handpieces.