title: Balanced force and rotary shaping.
abstract: Studies on instrument performance in clear acrylic canals have Professor Emeritus of Endodontics indicated that the helical angle of the cutting edge is a contributing factor Oklahoma City Oklahoma in instrument overload and failure. In clinical trials, changing the design of modern shaping instruments to eliminate the inclined angulations of the Private Practice in Endodontics cutting edges has proven to be beneficial by reducing the risk of fracture. Norman, Oklahoma Yet another benefit of a nonhelical cutting edge is that the flute space is accessible past the segment so that the fragment can be bypassed rather easily and the apex can be shaped with hand instruments. It appears that this feature may reduce the impact of a separated instrument.
authors.affiliation: University of Oklahoma, City Oklahoma, USA.
authors.forename: James B
authors.initials: JB
authors.lastname: Roane
mesh_terms: D003754:Dental High-Speed Equipment; D003764:Dental Materials / Q000737:chemistry; D004867:Equipment Design; D004868:Equipment Failure; D006801:Humans; D009532:Nickel / Q000737:chemistry; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods; D012399:Rotation; D014025:Titanium / Q000737:chemistry; D019415:Torque; D016474:Weight-Bearing
chemical_list: D003764:Dental Materials; C040654:titanium nickelide; D009532:Nickel; D014025:Titanium