Chemically Sharpening Patents (Class 76/24.5)
  • Longitudinally ground file having increased resistance to torsional and cyclic fatigue failure
    Patent number: 8789444
    Abstract: A method of producing an endodontic file that involves grinding in a plane substantially parallel to the longitudinal axis of a rotating dental instrument blank. By grinding the dental instrument blank in this manner, the torsional strength of the resulting endodontic file is not eroded during its production, thereby providing a file that is less susceptible to breakage during its use.
    Type: Grant
    Filed: April 8, 2013
    Date of Patent: July 29, 2014
    Inventor: William B. Johnson
  • Longitudinally ground file having increased resistance to torsional and cyclic fatigue failure
    Patent number: 8413330
    Abstract: A method of producing an endodontic file that involves grinding in a plane substantially parallel to the longitudinal axis of a rotating dental instrument blank. By grinding the dental instrument blank in this manner, the torsional strength of the resulting endodontic file is not eroded during its production, thereby providing a file that is less susceptible to breakage during its use.
    Type: Grant
    Filed: March 13, 2008
    Date of Patent: April 9, 2013
    Inventor: William B. Johnson