title: Biomechanical evaluation of different angle-stable locking plate systems for mandibular surgery.
abstract: OBJECTIVE
  To compare the initial stability and stability after fatigue of three different locking systems (Synthes(®), Stryker(®) and Medartis(®)) for mandibular fixation and reconstruction.
  
  
  METHODS
  Standard mandible locking plates with identical profile height (1,5 mm), comparable length and screws with identical diameter (2,0 mm) were used. Plates were fixed with six screws according a preparation protocol. Four point bending tests were then performed using artificial bone material to compare their initial stability and failure limit under realistic loading conditions. Loading of the plates was performed using of a servo hydraulic driven testing machine. The stiffness of the implant/bone construct was calculated using a linear regression on the experimental data included in a range of applied moment between 2 Nm and 6 Nm.
  
  
  RESULTS
  No statistical difference in the elastic stiffness was visible between the three types of plate. However, differences were observed between the systems concerning the maximal load supported. The Stryker and Synthes systems were able to support a significantly higher moment.
  
  
  CONCLUSIONS
  For clinical application all systems show good and reliable results. Practical aspects such as handling, possible angulation of screw fixation, possibility of screw/plate removal, etc. may favour one or the other plating system.
authors: Department of Cranio-Maxillofacial Surgery, Inselspital, Bern University Hospital, and University of Bern, Switzerland. Electronic address: contact@olivierlieger.ch.
authors: Olivier
authors: O
authors: Lieger
authors: Department of Cranio-Maxillofacial Surgery, Inselspital, Bern University Hospital, and University of Bern, Switzerland.
authors: Benoit
authors: B
authors: Schaller
authors: Institute for Surgical Technology and Biomechanics, University of Bern, Switzerland.
authors: Alexander
authors: A
authors: Bürki
authors: Institute for Surgical Technology and Biomechanics, University of Bern, Switzerland.
authors: Philippe
authors: P
authors: Büchler
mesh_terms: D001696:Biomechanical Phenomena; D001860:Bone Plates; D001863:Bone Screws; D000069343:Bone-Implant Interface / Q000503:physiopathology; D055119:Elastic Modulus; D004867:Equipment Design; D004868:Equipment Failure; D006801:Humans; D008334:Mandible / Q000601:surgery*; D063175:Mandibular Reconstruction / Q000295:instrumentation*; D008422:Materials Testing; D018583:Pliability; D013314:Stress, Mechanical; D013499:Surface Properties
keywords: Fracture osteosynthesis; Internal fixation device; Internal fracture fixation; Jaw fixation techniques; Locking screw/plates; Mandible