3D Visualization and Fatigue Simulation in Restored Human Teeth by using micro-CT Data

In a restored tooth, stresses at the tooth???restoration interface during masticatory processes may fracture the tooth or the restoration and cracks may grow and propagate. Therefore, numerical procedures and methodologies are welcome to simulate the behavior of a restored tooth and to evaluate its life before crack failure. In this paper, by using a CAD-FEM procedure and fatigue mechanic laws, the fatigue damage of a restored molar is numerically estimated. Tessellated surfaces of enamel and dentin were extracted by using segmentation and classification algorithms, by processing 2D image data. A friendly GUI, which drives user to select and visualize 3D tessellated surfaces, was developed in MatLab® environment. Then, the tooth boundary surfaces of enamel and dentin were created by lofting operations through crossing sections. A class II MOD cavity preparation was also added to the 3D model and tetrahedral mesh elements were generated. The fatigue simulation was performed by combining a preliminary non-linear FEA simulation with the classical mechanic laws. The regions with the shortest fatigue-life are located around the fillet of the class II MOD cavity, where the static stress is highest.