Patent ID: 7556498

Claim:
Contra-angle handpiece for driving a dental instrument connected to the contra-angle handpiece, the contra-angle handpiece comprising: an outer sleeve, said outer sleeve comprising a handle section, a neck section and a contra-angle handpiece head, wherein the handle section and the neck section are arranged at a nonzero first angle relative to each other and wherein the neck section and the contra-angle handpiece head are arranged at a nonzero second angle relative to each other, a head shaft having a transverse axis disposed in the contra-angle handpiece head for connection to the dental instrument, a substantially straight shaft for the transmission of drive movement through the handle section and the neck section to the head shaft, wherein the substantially straight shaft defines a single straight first longitudinal axis and has a proximal end, a distal end, and an intermediate section between the proximal end and the distal end, wherein the distal end is connected to the head shaft and wherein the distal end and the proximal end are substantially centrally spaced in the outer sleeve, and wherein the intermediate section is arranged eccentrically in the outer sleeve, and a coupling device positioned at an end of the contra-angle handpiece. opposite the contra-angle handpiece head, for connecting the contra-angle handpiece to an external drive unit, the coupling device having a second longitudinal axis that is a continuation of the first longitudinal axis of the substantially straight shaft so that drive movement from the coupling device to the head shaft is along a single straight longitudinal axis.