FIELD: medicine.
SUBSTANCE: endodontic file includes a handle adapted for attachment to a mechanical tip, configured to rotate in a predetermined rotational direction, and a spiral core. The spiral core comprises an internal spiral winding formed by metallic material wound in the said predetermined direction of rotation around the central core, formed by metal material between the opposite ends of the central core so as to form a unitary structure (18), wherein contact is maintained between the spiral core and the central core during endodontic file rotation in the root canal. The unitary structure has a generally conical longitudinal section, including a tip and an opposite wider end, and is held at the wider end by the handle. The outer surface of the spiral wire has an abrasive surface suitable for material removal from the root canal wall during endodontic file rotation in the root canal in the said predetermined direction. The spiral core comprises an inner spiral winding made of wire with a diameter of 0.12 to 0.20 mm, formed by a spirally wound wire and is wound in the said predetermined direction of rotation between the wider end of the spiral core and the endodontic file tip. The spiral winding further comprises a flexible reinforced part comprising an outer spiral winding of wire with larger diameter wound around the inner sprial winding retained by the handle and enclosing the upper portion of the unitary structure. The outer the spiral winding has a conical shape and dimensions to keep its lower end narrow enough to fit within the root canal.
EFFECT: invention improves flexibility and strength of file with the ability to adapt to the oval channel shape.
12 cl, 7 dwg
