【作者】 曾文；

【导师】 周天瑞；

【作者基本信息】 南昌大学 ， 材料加工工程， 2008， 博士

【摘要】 外耳重建是外科整形手术中最具挑战性的手术之一。其关键在于耳廓支架的构建。目前主要采用自体软骨手工雕刻和进口的高密度多孔聚乙烯材料组装而成。两者都不能满足患者的要求。本论文采用熔融挤压快速成形技术来完成外耳支架的构建,获得外形逼真的个性化外耳支架。并在此基础上结合传统的工艺,设计了聚氨酯—胶原复合外耳支架,改善其生物相容性。论文的研究工作包括两部分:外耳支架的快速成形制造研究和改善外耳支架的生物相容性的基础研究。外耳支架的快速成形制造研究包括外耳支架的三维重构设计、快速成形系统开发、快速成形工艺参数的优化的研究。本文在改善外耳支架生物相容性的基础研究中分别进行了低温等离子表面改性的研究和聚氨酯—胶原复合外耳支架的结构设计和成形工艺的研究。主要研究结果有:(1)在外耳的反求过程中,提出了包含耳廓软骨、耳廓肌肉和耳垂的外耳模型。获得的外耳形状更逼真、强度更高,可减少耳垂转位、耳甲腔及耳屏再造的手术。并首次提出了包含外耳道软骨的外耳三维重构,所获得的外耳形状逼真,并有利于外耳支架的固定,可防止外耳道再次闭锁。(2)外耳支架植入体内培养的动物实验结果表明,开始有炎症出现,随后炎症逐渐消失,轮廓逐渐清晰,与正常耳外形相似。可见,聚氨酯外耳支架的组织相容性好,且可以很好地保持外耳的形状,证明外耳支架的力学性能能满足要求。(3)聚氨酯支架经低温等离子表面改性后,表面变粗糙,在材料表面引入了大量的氧元素和氮元素,形成了大量的羰基和氨基等活性官能团,大大提高聚氨酯材料的表面亲水性,细胞培养实验证明这些表面性能的变化都有助于改善细胞在支架表面的粘附和生长。这种表面改性的方法,对于其它医用高分子材料植入物有一定的参考应用价值。(4)本文首先提出了将快速成形技术与传统的工艺相结合的方法,实现了聚氨酯-胶原复合支架的构建,并将支架设计成由聚氨酯材料形成大孔结构、胶原形成微孔结构的分级结构,不仅能满足外耳支架的力学性能,且由细胞实验证明其生物相容性得到很大提高。更多还原

【Abstract】 In plastic reconstruction surgeries, total auricular reconstruction for microtia is a challenge. The key point is the construction of a perfect framework. Presently autogenous costal sculpted cartilage and assembled MEDPOR are used widely. None of them can satisfy the need of patients. In this study an auricle framework is formed using fused deposition modeling method. A real like individuation human ear was obtained. On this basis, a polyurethane-collagen composite auricle framework was designed to improve its biocompatibility by combined with traditional method.The study includes two parts: research on rapid prototyping of auricle scaffold and fundamental research on improving biocompatibility of auricle scaffold. Research on rapid prototyping of auricle scaffold includes design of three-dimension reconstruction of auricle scaffold, develop of rapid prototyping system and optimize the process parameters of rapid prototyping. In fundamental research on improving biocompatibility of auricle scaffold, low temperature plasma on polyurethane surface, configuration design and forming technology of polyurethane-collagen composite auricle framework were performed. The main results of this study are as follows.In the course of ear reconstruction, a new ear model of auricle cartilage, auricle muscle and earlap was introduced. A more real and stronger ear was obtained. The operation of earlap transform and tragus reforger can be cut down. It is the first time to built ear model with external ear canal. This ear model forms a real like ear. This model is in favor of the scaffold fixation and can avoid the closure again of external ear canal.The result of animal experiment indicated that: in the start of ear scaffold implant, the inflammations appeared, in the following the inflammations disappeared gradually and contour of ear become clearly. It is similar to human ear. It shows that the polyurethane ear scaffold has a good histocompatibility. And the ear shape is not changed. It proved that the mechanics performances of ear scaffold are satisfied.In this study, the surface of polyurethane was modified by low temperature plasma with ammonia. The surface becomes roughness. Much oxygen elements and nitrogen elements are introduced in the scaffold surface, and some functional groups such as carbonyl groups and amidogen groups were exposed on the surface, which enhanced hydrophilic property of polyurethane. The cell culture experiments proved that the structure and the properties of the modified materials enhanced the cell adhesion and growth. This modified method can be spread to other polymeric biomaterials.A new forming process including of rapid prototyping and traditional method was designed to build polyurethane-collagen composite auricle framework. In this auricle framework, polyurethane forms macro-porous structures and collagen forms micro-porous structures. This composite auricle framework not only has a satisfied mechanics performance, but also its biocompatibility is improved greatly through cell culture experiments.更多还原