Analysis Of The3-D Finite Element Of Titanium Plate Implant Anchorage Maxillary Protraction

Objective:The author of this thesis selected and used the original statistics of spiral CT to build a3-D model of craniofacial complex, then applied proe software to build a model of titanium plate on the maxilla. A discussion of the variation law in terms of protraction force titanium plate implant anchorage, with different magnitudes and directions, on the bone suture and implant bone interface was carried out in the thesis, aiming to provide scientific support for the choices in the clinical force system.Method:1. To use spiral CT scan to gain the original statistics of2-D image. Based on software Mimics10.1、MSC. geomagic studio10.0Marc.mentat2005R3, build a3-D model of craniofacial complex.2. To use proe to build models of titanium plate and implant, and combine the two on the bone interface seamlessly.3. Simulating the real maxillary protraction condition of3-D finite element, impose protraction force on the titanium screw, supported by occipital bone macroporous edge and anterior frontal bone.4. To set the traction force ranging from1N to6N with an increase of1N, and the angle between the direction of the force and the frankfort horizontal plane ranging from0°to60°with an increase of10°. A pair of symmetric traction screws forms3kinds of angles with the central sagittal line, namely,30°,45°and60°, totaling108kinds of conditions. To analyze the impact of different traction force on craniofacial complex and calculate the statistics of the first main stress, equivalent stress and equivalent Von Mises stress on each joint under every condition. To compare, analyze and draw line graphs, stress distribution cloud chart, etc.Result:1. A complete3-D model of craniofacial complex has been acquired.2. A finite element3-D model of titanium plate has been acquired and attached to the maxilla seamlessly.3. The titanium plate implant traction force increases with the increase of the angle of traction.4. The force distribution is the most stable when force direction ranges from anterior inferior40°to60°, serving as the best traction angle. And it decreases with the increase of the angle.Conclusion:1. A complete3-D finite element model of titanium plate implant has been acquired, providing foundation for the experiment.2. The implantation of titanium plate implant on the maxilla3-D finite element model has been finished. The new maxilla-titanium plate implant complex meets the requirement of in the protraction experiment in terms of force.3. The enduring ability of the titanium plate implant and bone interface has been tested, with a conclusion that a small increase of force is affordable on the basis of4N, and the traction force is proportional to the suture stress. A stress of6N should not detach the implant or lead to bone rupture.4. The experiment showed, with the increase of the traction angle, the different stresses between the bone sutures would react accordingly. And the change would become smaller after40°, and becomes stabilized to60°. Therefore, it is believed that the best traction angle of titanium plant is40°to60°with the Frankfort horizontal plane.5. The force determines the change of bone stress. The change of traction screws has little impact on the change of bone suture stress without specific concentration area. Angle ranges from30°to60°is available for traction. Implantation can be carried out based on this to avoid from tooth root and fragile tissues.