A 3-D Fem Study On Biomechanical Characteristics Of Zygomaticomaxillary Suture Assessed With Implanting Retractive Forces To Maxilla Of Rhesus Monkey

[Objective] To construct the 3-D finite element model which contains zygomaticomaxillary and zygomatictemporal suture of craniofacial complex on the base of the established model which contains zygomaticotemporal suture to optimize the original model. Besides to analysis biomechanics characteristics of the reconstructive model with different retractive forces and elastic modulus of suture. In order to provided the experimental data for orthopedic treatment with implant retractive forces to maxilla.[Materials and Methods] CT images of the early growth monkeys’ craniofacial import to Mimics software to reconstruct the model and acquire the coordinates of zygomaticomaxillary suture’s mark points. Then using the coordinates to reconstruct 3-D finite element model of zygomaticomaxillary suture in Ansys software. In 6 groups elastic modulus values of sutures (Six different sets of mechanical properties were used:2.24MPa、38.6MPa、 50MPa、70.3MPa、0.4GPa、1.37GPa),4 groups traction value of retractive forces(Under the implants anchorage retractive forces parallel to the occlusion,four differnt groups of force were used:150g/side、300g/side 、450g/side、600g/side),3 groups traction direction of retractive forces(Under implants anchorage 500g/side retractive forces, three different groups of angle of occlusional plane were use:angle of traction 0、15、30°), to observe craniofacial change of mark’ displacement and stress.To check the stress distribution of zygomatictemporal and zygomaticomaxillary suture.[Result]1.The establishment of 3-D finite element model which contains zygomaticomaxillary and zygomatictemporal suture of craniofacial complex model, which was included zygomatic temporal sutures and zygomaticomaxillary sutures of the both sides, and implants% titanium plate.2. Suture’s modulus of elasticity of 70.3MPa produced significant variations in the constant retractive forces.3. When the modulus of elasticity is 70.3MPa,the stress and displacement of markers is a linear relationship with the different strength force which in the same direction. Changing the angle of traction from 0°、15°and 30°, zygomatictemporal suture stress distribution is almost constant, less affected by changes in the angle of traction; zygomaticomaxillary suture stress distribution area changes significantly, some tensile stress area becomes compressive stress area,the compressive stress areas of zygomaticomaxillary suture are increasing.[Conclusion]1.Reconstruct a 3-D finite element model which contains zygomaticomaxillary and zygomatictemporal suture of craniofacial complex model. The Model do not need to manually set the width and position of the bone joints, it has better simulation and applicability. Besides build an interactive mechanical system, in order to make comparative study about the suture mechanical characteristics 2. The interactive mechanical system with zygomaticomaxillary and zygomatictemporal suture showed the opposite of two kinds of stress:zygomatictemporal suture showed tensile stress,and zygomaticomaxillary suture showed compressive stress in the same time. 3.Stress distribution of zygomaticomaxillary suture is a linear relationship with the different strength force which in the same direction. Changing the angle of traction fromO、15、30°, stress distribution area of zygomatictemporal suture change significantly, part of the tensile stress becomes compressive stress region,and zygomaticomaxillary suture of compressive stress area.