An Evaluation Of The Bonding Quality Of Orthodontic Bracket Using Three Dimensional Finite Element Method

ObjectiveThe bonding quality of orthodontic bracket is usually measured by the in vitro bonding strength test and clinical control investigation. Neither the in vitro bonding strength test nor the clinical control investigation is perfect. As the development of modern computer technique there comes a new academic stress a-nalysis method - finite element method. The three dimensional finite element method (3D -FEM) is an advanced, effective and conventional mathematical method in orthodontic biomechanics and has a lot of virtues. Using the 3D -FEM the present investigation studied the quality of orthodontic bracket, three debonding methods which were usually used by in vitro bonding strength test were compared by the stress and displacement changing. The aim was to compare the advantage and disadvantage of different debonding methods, and then compared with the in vitro study to get the effect of the error on results for the purpose of throwing light on clinical therapy and the research.Materials and MethodsAccording to the compute tomography ( CT) scanning image, the average incisor information of the Chinese people and the normal size of standard Edgewise incisor bracket, The three dimensional finite element model of the tooth -adhesive - bracket system was built. The total model involves 8280 elements and 10397 nodes. Simulating the load methods of in vitro bonding strength test of shear, tensile and torsion loads of the same Newton were loaded at the corresponding location. The stress distribution and displacement changing of different...