The invention is an endodontic handpiece, its control system and method of use for rotating an endodontic file to clean a root canal. The invention control system provides for rotating a file clockwise or counterclockwise through a desired first arc of rotation and, next, sequentially rotating said instrument in the opposite direction of the first arc of rotation through a second arc of rotation, wherein the first arc of rotation exceeds the second arc of rotation such that sequentially occurring rotations cause debris material removed in cleaning said canal to be ejected upwardly from said clean surfaces as such file is advanced in cleaning said canal.