Abstract

This paper discussed the size of 3 D-printed personalized titanium plates that can gain maximum stability of mandibular fracture and minimize stress shielding through finite element analysis. A 3 D virtual model of mandible with mandibular angle fracture was created from the CT data of patient. 3 D-printed personalized titanium plates varying in length and thickness were designed, and finite element analysis was performed under different loading conditions and fracture healing periods. After that, the stress distribution and deformation of the mandible with gonial fracture could be observed, and the stress shielding rate could be obtained. Finally, SPSS21.0 was used for statistical analysis. The results of finite element analysis indicated that as the thickness of titanium plates and the healing time decreased, the maximum displacement increased, under a certain condition in which the pore size, the width, the hole distance and the bridge spacing were 2.0 mm, 4.0 mm, 6.0 mm, 12.0 mm, respectively. What’s more, in this condition, the thicker the titanium plate and the shorter the healing time were, the higher the stress shielding was at central occlusion. When the thickness of the personalized 3 D-printed titanium plate was 1.0 mm, the maximum displacement tended to be stable and the stress shielding was minimized. It can not only improve the bone stability after tension band fixation, but also minimize the stress shielding, which is expected to expand the indications of tension band fixation.

摘要

本文讨论了 3 D 打印个性化钛板的尺寸，通过有限元分析可以获得下颌骨骨折的最大稳定性和最小化应力屏蔽。根据患者的 CT 数据创建下颌角骨折的 3D 虚拟模型。设计了3块不同长度和厚度的D打印个性化钛板，并在不同的加载条件和骨折愈合周期下进行了有限元分析。之后观察下颌角骨折的应力分布和变形情况，得到应力遮挡率。最后使用SPSS21.0进行统计分析。有限元分析结果表明，随着钛板厚度和愈合时间的减小，最大位移增大，在孔径、宽度、孔距和桥距分别为2.0 mm、4.0 mm、6.0 mm、12.0 mm的一定条件下。而且，在这种情况下，钛板越厚、愈合时间越短，中心咬合处的应力遮挡就越高。当个性化3D打印钛板厚度为1.0 mm时，最大位移趋于稳定，应力遮挡最小。既能提高张力带固定后的骨稳定性，又能最大限度地减少应力遮挡，有望扩大张力带固定的适应证。钛板越厚、愈合时间越短，中心咬合处的应力遮挡程度越高。当个性化3D打印钛板厚度为1.0 mm时，最大位移趋于稳定，应力遮挡最小。既能提高张力带固定后的骨稳定性，又能最大限度地减少应力遮挡，有望扩大张力带固定的适应证。钛板越厚、愈合时间越短，中心咬合处的应力遮挡程度越高。当个性化3D打印钛板厚度为1.0 mm时，最大位移趋于稳定，应力遮挡最小。既能提高张力带固定后的骨稳定性，又能最大限度地减少应力遮挡，有望扩大张力带固定的适应证。