Study on the Center of Resistance of Tooth Based on Spatial Kinematics

This paper presents a three-dimensional method to locate the center of resistance (CRE) with a spatial kinematic method and finite element analysis. Firstly, finite element analyses with hypoelastic and also isotropic constitutive model of periodontal ligament were conducted to get the tooth displacements under various boundaries. Then a spatial kinematic method was used to solve the location of CRE with the derived displacements. Finally, the influences of the type of constitutive model, the magnitude and direction of torque on the location of CRE were analyzed. The results make a good agreement with experimental data in literatures; and it shows that there is not a fixed location of CRE, the location of resistance center is in a range rather than on a fixed point.