Comparative evaluation of two osteosynthesis methods on stability following sagittal split ramus osteotomy.
BACKGROUND
The aim of this study was to employ the finite element method (FEM) to compare the stability of 2.0 mm titanium screws in a triangular configuration with that of a 2.0 mm titanium miniplate as osteosynthesis material following bilateral sagittal split osteotomy.


METHODS
A model of the mandible was produced, consisting of 19,854 elements and 4285 nodes. The mechanical parameters of the materials investigated were taken from the literature and notified by the manufacturer.


RESULTS
On condition that the materials were subjected only to their respective ultimate tensile stress, it was possible to neutralise a masticatory force of 1246 N (Newtons) with the miniplate and of 1675 N with the bicortical triangular screw configuration. The strain limit was determined by the peri-implant bone and not the osteosynthesis material.


CONCLUSIONS
The finite element method (FEM) appears to be suitable for simulating complex mechanical stresses in the maxillofacial area, as also confirmed by the agreement between our data and those in the literature, and with clinical experience. It should enable considerable savings to be made in terms of time, material and animal experiments in the future development of osteosynthesis materials and techniques.
Maurer
Peter
P
Department for Oral and Plastic Maxillofacial Surgery, Klinik und Poliklinik für Mund, Kiefer- und plastische Gesichtschirurgie, Martin Luther-University, Halle-Wittenberg, Halle, Germany. peter.maurer@medizin.uni-halle.de
Knoll
Wolf-Dietrich
WD
Schubert
Johannes
J
D001696:Biomechanical Phenomena; D001732:Bite Force; D001860:Bone Plates; D001863:Bone Screws; D003198:Computer Simulation; D004867:Equipment Design; D020342:Finite Element Analysis; D006801:Humans; D008334:Mandible / Q000503:physiopathology / Q000601:surgery*; D008954:Models, Biological; D010027:Osteotomy / Q000295:instrumentation / Q000379:methods*; D013314:Stress, Mechanical; D014025:Titanium / Q000737:chemistry
D014025:Titanium