Abstract: The angle piece head drives an instrument for operating on dental roots and includes a body having a generally cylindrical cavity and an instrument-holding core in the cavity. The core is shaped to receive and hold the instrument and moves axially and pivotally. The instrument-holding core includes a groove having an offset engaging therewith. The offset engages with one or the other of the two edges of the groove such that the rotation thereof transmits an alternating axial movement to the instrument while enabling same to rotate about the axis of the instrument. The groove includes two portions that extend on either side of a median area. For each portion, the height, namely the distance that separates the two edges, increases from the median area to each end of the groove.

Abstract: The angle piece head drives an instrument for operating on dental roots and includes a body having a generally cylindrical cavity and an instrument-holding core in the cavity. The core is shaped to receive and hold the instrument and moves axially and pivotally. The instrument-holding core includes a groove having an offset engaging therewith. The offset engages with one or the other of the two edges of the groove such that the rotation thereof transmits an alternating axial movement to the instrument while enabling same to rotate about the axis of the instrument. The groove includes two portions that extend on either side of a median area. For each portion, the height, namely the distance that separates the two edges, increases from the median area to each end of the groove.