A finite element analysis and experimental study of human edentulous mandible

By the means of finite element analysis (FEa), biomechanical behaviors of human mandible have been widely studied over decades. Many different types of simulation of muscle forces have been employed in studies to increase the reality of mastication environment. Among these studies, Cruz et al (2003)'s calculation of muscle forces was well accepted. However, these simulations have not been verified experimentally as seen in literatures. In this study, a three dimensional (3D) finite element model of human mandible was created from CT images of a cadaver mandible bone. 4 pairs of muscle forces was applied to this 3D model based on a calculation by using Cruz et al (2003)'s method. The exact cadaver bone was used in an experimental testing rig to evaluate strain distribution and, hence, to verify the results of FEa. A set of different sizes of loads which matches with the one used in FE study was applied to the cadaver bone. Strain gauges were employed to gain data of strain distribution on the bone. The experimental result shows that the trend of stress/strain during increase or decrease of muscle forces coincides with FE result. This verifies the masticator muscle force calculation of Cruz et al (2003) to be correct.