Melt electrowriting in tissue engineering: from scaffold design and regenerative microenvironments to clinical translation

Melt electrowriting (MEW) is a high-resolution additive manufacturing technique that enables the programmable deposition of microfibers with defined architecture, pore geometry, and mechanical properties. In tissue engineering, its major value lies not only in fabricating ordered fibrous scaffolds, but also in translating tissue-specific regenerative requirements into controllable scaffold designs. This review summarizes MEW-based scaffold strategies from the perspective of key regenerative demands: mechanical matching, cell guidance, vascular support, immune regulation, interface/layered structure reconstruction, bioactive regulation, and degradation coordination. Rather than treating MEW applications as a uniform field, we distinguish areas with relatively strong preclinical support from those that remain exploratory. Current evidence suggests that MEW has shown encouraging preclinical outcomes in bone repair and periodontal or soft–hard tissue interface regeneration, whereas applications in vascular grafts, skin equivalents, cardiac patches, nerve conduits, and soft-tissue augmentation are still largely limited to structural biomimicry, in vitro validation, short-term animal studies, or early functional assessment. We further discuss major barriers to translation, including limited material diversity, insufficient long-term in vivo evidence, lack of large-animal and clinical studies, and unresolved standardization and regulatory issues. By integrating regenerative requirements, scaffold-design strategies, the strength of in vivo evidence, and translational maturity, this review provides a requirement-oriented framework for critically evaluating MEW-based tissue-engineering applications.