Scaffold-based bone tissue engineering has been extensively developed as a potential means to treatment of large bone defects. To enhance the biomechanical performance of porous tissue scaffolds, computational design techniques have gained growing popularity attributable to their compelling efficiency and strong predictive features compared with time-consuming trial-and-error experiments. Nevertheless, the mechanical stimulus necessary for bone regeneration, which characterizes dynamic nature due to continuous variation in the bone-scaffold construct system as a result of bone-ingrowth and scaffold biodegradation, is often neglected. Thus, this study proposes a time-dependent mechanobiology-based topology optimization framework for design of tissue scaffolds, thereby developing an ongoing favorable microenvironment and ensuring a long-term outcome for bone regeneration. For the first time, a level-set based topology optimization algorithm and a time-dependent shape derivative are developed to optimize the scaffold architecture. In this study, a large bone defect in a simulated 2D femur model and a partial defect in a 3D femur model are considered to demonstrate the effectiveness of the proposed design method. The results are compared with those obtained from stiffness-based topology optimization, time-independent design and typical scaffold constructs, showing significant advantages in continuing bone ingrowth outcomes.

基于支架的骨组织工程已被广泛开发为治疗大骨缺损的潜在手段。为了提高多孔组织支架的生物力学性能，与费时的反复试验相比，计算设计技术因其引人注目的效率和强大的预测功能而日益受到欢迎。然而，由于骨向内生长和支架生物降解的结果，由于骨骼-支架结构系统的连续变化而导致的动态特性，骨骼再生所必需的机械刺激通常被忽略。因此，本研究提出了一种基于时间的基于力学生物学的拓扑优化框架，用于组织支架的设计，从而开发出持续良好的微环境，并确保骨再生的长期结果。第一次，开发了基于水平集的拓扑优化算法和随时间变化的形状导数，以优化支架架构。在这项研究中，模拟的2D股骨模型中的大骨缺损和3D股骨模型中的部分缺损被认为证明了所提出的设计方法的有效性。将结果与从基于刚度的拓扑优化，与时间无关的设计和典型的脚手架构造获得的结果进行了比较，显示出在持续的骨长入结果中的显着优势。在这项研究中，模拟的2D股骨模型中的大骨缺损和3D股骨模型中的部分缺损被认为证明了所提出的设计方法的有效性。将结果与从基于刚度的拓扑优化，与时间无关的设计和典型的脚手架构造获得的结果进行了比较，显示出在持续的骨长入结果中的显着优势。在这项研究中，模拟的2D股骨模型中的大骨缺损和3D股骨模型中的部分缺损被认为证明了所提出的设计方法的有效性。将结果与从基于刚度的拓扑优化，与时间无关的设计和典型的脚手架构造获得的结果进行了比较，显示出在持续的骨长入结果中的显着优势。