Nerve guide conduits (NGCs), as alternatives to nerve autografts and allografts, have been widely explored as an advanced tool for the treatment of peripheral nerve injury. However, the repairing efficiency of NGCs still needs significant improvements. Functional NGCs that provide a more favorable microenvironment for promoting axonal elongation and myelination are of great importance. In recent years, 3D printing technologies have been widely applied in the fabrication of customized and complex constructs, exhibiting great potential for tissue engineering applications, especially for the construction of functional NGCs. In this review, we introduce the 3D printing technologies for manufacturing functional NGCs, including inkjet printing, extrusion printing, stereolithography-based printing and indirect printing. Further, we summarize the current methods and strategies for constructing functional NGCs, such as designing special conduit architectures, using appropriate materials and co-printing with different biological cues. Finally, the challenges and prospects for construction of functional NGCs are also presented.

中文翻译：

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功能性神经导管的 3D 打印

神经导管 (NGC) 作为神经自体移植物和同种异体移植物的替代品，已被广泛探索为治疗周围神经损伤的先进工具。然而，NGCs的修复效率仍需显着提高。为促进轴突伸长和髓鞘形成提供更有利的微环境的功能性 NGC 非常重要。近年来，3D打印技术已广泛应用于定制和复杂结构的制造，在组织工程应用中展现出巨大潜力，特别是在功能性NGCs的构建方面。在这篇综述中，我们介绍了用于制造功能性 NGC 的 3D 打印技术，包括喷墨打印、挤压打印、基于立体光刻的打印和间接打印。进一步，我们总结了当前构建功能性 NGC 的方法和策略，例如设计特殊的管道架构、使用适当的材料以及与不同的生物线索共同打印。最后，还提出了构建功能性NGC的挑战和前景。