title: Perpendicular pull-out force of locking versus non-locking plates in thin cortical bone using a canine mandibular ramus model.
abstract: OBJECTIVE
  To compare the holding strength of a conventional plate-screw construct with a locking plate-screw construct in the thin cortical bone of the canine mandibular ramus.
  
  
  METHODS
  Mechanical study.
  
  
  METHODS
  Paired cadaveric canine mandibles (n = 10 pairs).
  
  
  METHODS
  Perpendicular pull-out testing was performed on 2.0-mm limited-contact dynamic compression plate (LC-DCP)-screw constructs and 2.0-mm string-of-pearls (SOP) plate-screw constructs applied to the ramus of the canine mandible. Pull-out force was applied perpendicular to the long axis of the plates. Construct stiffness and load at failure were determined from load-displacement curves and method of failure was determined from high speed digital video recordings. A paired t-test was used to compare mean construct stiffness and load at failure between groups.
  
  
  RESULTS
  SOP plate-screw constructs had a significantly higher mean construct stiffness and load at failure than did LC-DCP-screw constructs. LC-DCP constructs failed by screw pull-out while bone slicing and fracture were prominent mechanisms of failure for SOP constructs.
  
  
  CONCLUSIONS
  SOP plate-screw constructs sustained a significantly higher perpendicular load at failure than did LC-DCP-screw constructs.
authors.affiliation: Department of Veterinary Clinical Sciences, Dr. W. Eugene and Linda Lloyd Veterinary Medical Center, College of Veterinary Medicine, Iowa State University, 1600 South 16th Street, Ames, IA 50011, USA. emiller@iastate.edu
authors.forename: Emily I
authors.initials: EI
authors.lastname: Miller
authors.forename: Anthony E
authors.initials: AE
authors.lastname: Acquaviva
authors.forename: David J
authors.initials: DJ
authors.lastname: Eisenmann
authors.forename: Richard T
authors.initials: RT
authors.lastname: Stone
authors.forename: Karl H
authors.initials: KH
authors.lastname: Kraus
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D001860:Bone Plates; D001842:Bone and Bones / Q000502:physiology*; D002102:Cadaver; D004285:Dogs; D019544:Equipment Failure Analysis / Q000379:methods; D008297:Male; D008334:Mandible; D008422:Materials Testing / Q000379:methods / Q000662:veterinary