Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing 100871, China.
Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing 100871, China.
Med Eng Phys. 2017 Sep;47:176-183. doi: 10.1016/j.medengphy.2017.06.015. Epub 2017 Jun 24.
Reconstruction of segmental defects in the mandible remains a challenge for maxillofacial surgery. The use of porous scaffolds is a potential method for repairing these defects. Now, additive manufacturing techniques provide a solution for the fabrication of porous scaffolds with specific geometrical shapes and complex structures. The goal of this study was to design and optimize a three-dimensional tetrahedral titanium scaffold for the reconstruction of mandibular defects. With a fixed strut diameter of 0.45mm and a mean cell size of 2.2mm, a tetrahedral structural porous scaffold was designed for a simulated anatomical defect derived from computed tomography (CT) data of a human mandible. An optimization method based on the concept of uniform stress was performed on the initial scaffold to realize a minimal-weight design. Geometric and mechanical comparisons between the initial and optimized scaffold show that the optimized scaffold exhibits a larger porosity, 81.90%, as well as a more homogeneous stress distribution. These results demonstrate that tetrahedral structural titanium scaffolds are feasible structures for repairing mandibular defects, and that the proposed optimization scheme has the ability to produce superior scaffolds for mandibular reconstruction with better stability, higher porosity, and less weight.
下颌骨节段性缺损的重建仍然是颌面外科的一个挑战。使用多孔支架是修复这些缺损的一种潜在方法。现在，增材制造技术为制造具有特定几何形状和复杂结构的多孔支架提供了一种解决方案。本研究的目的是设计和优化用于下颌骨缺损重建的三维四面体钛支架。采用固定支柱直径 0.45mm 和平均孔径 2.2mm，根据人下颌骨 CT 数据设计模拟解剖缺损的四面体结构多孔支架。采用基于均匀应力概念的优化方法对初始支架进行优化，实现最小重量设计。初始支架和优化支架的几何形状和力学性能比较表明，优化支架的孔隙率更大，为 81.90%，且具有更均匀的应力分布。这些结果表明，四面体结构钛支架是修复下颌骨缺损的可行结构，所提出的优化方案具有产生更好稳定性、更高孔隙率和更轻重量的下颌骨重建用优质支架的能力。
