US Patent 7771198 Dental power instruments, such as endodontic instruments, and contra-angle handpiece

A dental power instrument, in particular, an endodontic instrument, has an operative part (2) at one end and a handle (3) at the opposite end. The handle (3) of the dental instrument is provided with a rotary drive (4) which, when mounted in the head (5) of a handpiece, can directly engage with a rotary drive (4′) upstream of the head. The rotary drive (4) can be inserted and withdrawn independently of the rotary drive (4′) associated with the head of the handpiece, and rotates in the same direction as the rotary drive (4′) associated with the handpiece. Also provided is a handpiece head (5) and a dispenser (30) for such dental power instruments.