Biological additive manufacturing (Bio-AM) has emerged as a promising approach for the fabrication of biological scaffolds with nano- to microscale resolutions and biomimetic architectures beneficial to tissue engineering applications. However, Bio-AM processes tend to introduce flaws in the construct during fabrication. These flaws can be traced to material nonhomogeneity, suboptimal processing parameters, changes in the (bio)printing environment (such as nozzle clogs), and poor construct design, all with significant contributions to the alteration of a scaffold’s mechanical properties. In addition, the biological response of endogenous and exogenous cells interacting with the defective scaffolds could become unpredictable. In this review, we first described extrusion-based Bio-AM. We highlighted the salient architectural and mechanotransduction parameters affecting the response of cells interfaced with the scaffolds. The process phenomena leading to defect formation and some of the tools for defect detection are reviewed. The limitations of the existing developments and the directions that the field should grow in order to overcome said limitations are discussed.

中文翻译：

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基于挤压的 3D（生物）打印组织工程支架：工艺-结构-质量关系

生物增材制造 (Bio-AM) 已成为制造具有纳米到微米级分辨率和有利于组织工程应用的仿生结构的生物支架的有前途的方法。然而，生物增材制造工艺往往会在制造过程中在构造中引入缺陷。这些缺陷可以追溯到材料的不均匀性、次优的加工参数、（生物）打印环境的变化（例如喷嘴堵塞）和糟糕的构造设计，所有这些都对支架机械性能的改变有重大贡献。此外，内源性和外源性细胞与有缺陷的支架相互作用的生物反应可能变得不可预测。在这篇综述中，我们首先描述了基于挤出的 Bio-AM。我们强调了影响与支架连接的细胞反应的显着结构和机械转导参数。回顾了导致缺陷形成的过程现象和一些缺陷检测工具。讨论了现有发展的局限性以及该领域应该发展以克服所述局限性的方向。