Patent ID: 9585731
Date: 2017-03-07
CPC Classifications: A61C

Claim:
1. An endodontic file comprising: a handle adapted for attaching to a motorized handpiece configured for rotation in a predetermined direction of rotation; a spiral cord comprising an inner helical winding formed of a metallic material wound in said predetermined direction of rotation around a central cord formed of a metallic material between opposite ends of the central cord so as to form an integrated structure that retains contact between the spiral cord and the central cord during rotation of the endodontic file within a root canal; said integrated structure having a generally conical cross-section including a narrow tip end and an opposite wider end and being supported at the wider end by the handle; and an outer surface of the spiral cord having an abrasive surface operable for removing material from a wall of the root canal upon rotation of the endodontic file within the root canal in said predetermined direction; wherein the spiral cord comprises the inner helical winding of narrow diameter wire that constitutes a helically wound wire and is wound in said predetermined direction of rotation between the wider end of the spiral cord and the tip end of the endodontic file; and wherein the spiral cord further comprises a reinforced portion comprising an outer helical winding of larger diameter wire wound around the inner helical winding being supported by the handle and covering at least an upper section of the integrated structure and having an active portion that extends towards the tip and has an abrasive outer surface.