A method, and handpiece for performing the method, for controlling a drive device for moving a root canal instrument having a drive shaft and at least one cutting edge for preparing a root canal, and at least one drive motor being operated by a control unit. The root canal instrument is moved in at least one reciprocal movement in a first direction of rotation over a predetermined first angle of rotation and subsequently in a second direction of rotation opposite to the first direction of rotation over a predetermined second angle of rotation. After the at least one reciprocal movement, the root canal instrument is rotated over at least one third angle of rotation.
