3DP成形人工骨多孔支架研究

发布时间：2018-03-07 22:17

本文选题：三维打印　切入点：分子动力学　出处：《西北工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：各种疾病、意外造成的骨缺损在临床中十分常见。不同于人的皮肤等软组织器官,人骨的自我修复能力较弱,很难实现自我修复。尤其在严重车祸情况,下肢体的缺损会使病患失去运动技能。目前临床应用最多的人工骨是以金属、碳纤维等材料制成,在其植入人体后,自始至终都是以异物的形式存在,不断刺激机体引发排斥反应,给病患带来痛苦。骨缺损最理想的修复方法是在人体内植入可降解的人工骨支架,这些支架携带人骨细胞在植入人体后,最终会被人体降解,它的位置会由人骨取代,成长为真正的人骨,而不会引发排斥反应。传统方法制备的可降解骨支架外形不匹配,内部孔隙也难以有效控制,这不利于骨支架的成活,而借助于3D打印技术可以实现孔隙可控,外形精确的快速个性化骨支架的制备。本研究从骨缺损修补的前景与方向出发,探讨了NBCA/HA复合材料对骨支架的性能影响,对比了几种方法设计的骨支架的性能,优化了骨支架制备的参数。首先,阐述了人工骨支架在骨组织工程中的应用,介绍了人工骨支架的材料与制备方式,对比了不同材料、不同制备方式的优缺点,突出了本文所研究的采用3DP方式制备的可降解生物陶瓷骨支架的优势。其次,研究了骨支架的设计方法,主要包括骨支架的密质骨设计与松质骨的设计。骨支架的密质骨轮廓通过病患的CT图片经过三维重构获得,松质骨的结构则通过降维设计的方法,在二维图片上设计微孔再经过三维重构获得三维的疏松多孔结构。然后,对骨支架材料性能设计进行了探究,提出了一种利用分子动力学原理预测材料性能的方法,利用该方法研究了NBCA材料与HA材料之间的相互作用机理,探究了NBCA对HA材料机械性能的影响,计算出NBCA/HA复合体系的弹性模量,并经纳米压痕仪实验验证了复合材料的分子动力学计算结果。最后,对采用随机法、网格法、CAD法设计的松质骨支架进行了机械性能与生物性能的测试,包括:支架的抗压强度测试、孔隙率、孔径分布、微观形貌、相对渗透率等,并对这几种方法设计的骨支架性能进行了对比。
[Abstract]:Bone defects caused by various diseases and accidents are very common in clinic. Unlike soft tissue organs such as human skin, human bone is weak in self-repair and difficult to self-repair, especially in serious car accidents. A defect in the lower limb can cause the patient to lose his motor skills. At present, the most commonly used artificial bone is made of metal, carbon fiber and other materials. After it is implanted into the human body, it always exists in the form of a foreign body. The ideal way to repair a bone defect is to put degradable artificial bone scaffolds in the human body, which carry human bone cells and are eventually degraded by the human body. It is replaced by a human bone and becomes a real human bone without causing rejection. The biodegradable bone scaffolds made by traditional methods do not match the shape and the internal pores are difficult to control effectively, which is not conducive to the survival of the bone scaffolds. With the help of 3D printing technology, the rapid and individualized bone scaffolds with controllable pores and precise shape can be prepared. The effect of NBCA/HA composite materials on the properties of bone scaffolds was discussed from the perspective and direction of bone defect repair. The properties of bone scaffold designed by several methods were compared and the parameters of bone scaffold preparation were optimized. Firstly, the application of artificial bone scaffold in bone tissue engineering was described, the materials and preparation methods of artificial bone scaffold were introduced, and different materials were compared. The advantages and disadvantages of different preparation methods highlight the advantages of biodegradable bioceramic bone scaffolds prepared by 3DP in this paper. Secondly, the design method of bone scaffolds is studied. The outline of dense bone of bone scaffold is obtained by three-dimensional reconstruction of CT images of patients, and the structure of cancellous bone is designed by reducing dimension. The porous porous structure of the bone scaffold was obtained by 3D reconstruction. Then, a method of predicting the properties of the bone scaffold by molecular dynamics was proposed. The interaction mechanism between NBCA material and HA material was studied by this method. The influence of NBCA on mechanical properties of HA material was investigated. The elastic modulus of NBCA/HA composite system was calculated. Finally, the mechanical and biological properties of the cancellous bone scaffold designed by random method and grid CAD method were tested. Including: compressive strength test, porosity, pore size distribution, micromorphology, relative permeability and so on. The performance of bone scaffold designed by these methods was compared.
【学位授予单位】：西北工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R68;R318.08

【相似文献】