Precision and customization in regenerative medicine: The role of coaxial 3D printing

Coaxial three-dimensional (3D) printing enables precise, multi-material deposition, demonstrating strong potential across diverse fields, including industrial monitoring, health sensing, artificial intelligence (AI) hardware, and food packaging. Its core value is prominently realized in the biomedical domain, where it has revolutionized tissue engineering. The present review consolidates advancements in 3D coaxial bioprinting across diverse biomedical applications, focusing on its transformative potential in vascularized tissue engineering, spatiotemporal drug delivery, and patient-specific disease modeling. This review also explored unresolved challenges, such as bioink optimization and functional vascularization, while proposing integrative solutions that combine coaxial printing with AI and hybrid fabrication strategies. The versatility of coaxial 3D printing is evident in its numerous biomedical applications, such as cardiovascular tissue engineering, skin regeneration, bone repair, and functional muscle constructs. In bone tissue engineering, coaxial printing facilitates vascularization and osteochondral regeneration through spatially controlled bioink and scaffold design. Applications extend to cartilage repair, neuromuscular junction modeling, and tumor microenvironment replication. Despite progress, challenges persist in optimizing bioink rheology, achieving functional vascularization, and scaling production for clinical application. Notably, the integration of advanced materials, such as hydrogels and inorganic salts, with hybrid strategies, including electrospinning and sacrificial printing, highlights the synergistic potential of coaxial bioprinting to transform regenerative medicine, drug screening, and personalized therapies. Ongoing innovations in multi-scale, multi-cellular printing can bridge the gap between engineered constructs and biological functional tissues.