Advanced 3D Bioprinting Technology for Cartilage Engineering and Regeneration

Articular cartilage defects, caused by trauma or degenerative changes, pose significant challenges due to the restricted self-repair capability of the cartilage tissues. Current clinical treatments, such as autologous transplantation and microfracture surgery, often fail to achieve complete restoration of functionality. Advanced 3D bioprinting technology offers a promising strategy by facilitating the precise construction of biomimetic scaffolds. This review examines the application of 3D bioprinting in cartilage regeneration, emphasizing the key technologies such as inkjet, extrusion, stereolithography, and digital-light-processing printing, alongside advancements in material innovations involving synthetic, natural, and composite polymers. It discusses strategies for optimizing scaffold design, including pore structure, mechanical properties, and bioactive factor integration. The review also examines monophasic, biphasic, and gradient scaffolds, emphasizing their potential to mimic native tissue hierarchies and improve repair outcomes. Despite advancements, challenges, including long-term efficacy, mechanical stability, and clinical translation, remain. Future research should emphasize interdisciplinary collaboration to advance bioink formulation, printing precision, and scalable manufacturing, ultimately enhancing cartilage regeneration therapies.