Extrusion‐Based Bioprinting of Living Bioinks for Tissue and Organ Engineering

Recapitulating the structural complexity of native tissues is a central challenge in tissue engineering, as tissue architecture critically influences cellular maturation and physiological function. Among 3D bioprinting technologies, extrusion‐based bioprinting (EBB) has emerged as the predominant platform for fabricating complex, heterogeneous, and large‐scale tissues, despite inherent limitations in printing speed and resolution. In this review, we examine the defining advantage underlying EBB's widespread adoption: its exceptional versatility. We discuss the broad range of living bioinks and biomaterial inks compatible with extrusion, emphasizing the ease with which multiple materials and cell populations can be integrated within a single construct. We then examine how support matrices and advanced printhead geometries have expanded the accessible material and architectural space, enabling the fabrication of soft, freeform, anisotropic, and multicompartment tissues. We critically evaluate the fundamental physical constraints of extrusion, particularly the tradeoff between printing resolution and cell‐damaging shear stress, and highlight strategies that transform these limitations into new biofabrication capabilities. Finally, we identify 4D bioprinting, high‐speed fabrication, and in situ bioprinting as three emerging frontiers that may define the next generation of EBB for tissue engineering and regenerative medicine.