Review of biomechanical models used in studying the biomechanics of reconstructed mandibles.

This study looked at computer and physical biomodels used to study the biomechanical performance of mandibular reconstruction, reviews the literature and explains the strengths and limitations of the models. Electronic databases (Pubmed, Medline) were searched. 17 articles were selected. Computer biomodels can be divided into virtual biomodels (mainly used for clinical diagnosis and treatment planning) and computational models (e.g. finite element analysis), they can predict areas most likely to fail based on internal stress distribution and areas of maximum stress concentration. Physical biomodels include: rapid prototyping, animal bone, human cadaveric bone, and bone substitute models. Physical models allow testing on a gross level to give fatigue performance and fracture strength. The use of bone substitutes allows a more consistent specimen size and a reduction in sample size. Some commercially available products can replicate the material properties of bone. The use of any biomodel depends on the question being asked: the bending strength of a reconstruction plate would necessitate a three point bending test; the biomechanical performance of a new method of reconstruction (e.g. the mandibular modular endoprosthesis) would necessitate finite element analysis to predict areas of likely failure and also a physical biomodel to look at fatigue failure.