Multimaterial and Multidimensional Bioprinting in Regenerative Medicine: Advances, Limitations, and Future Directions.

3D bioprinting has been advanced from creating simple, static structures with single materials to sophisticated multimaterial and multidimensional designs. This evolution has improved printing precision, the range of application and dynamic functionality. Multimaterial and multidimensional bioprinting represent significant advancements in regenerative medicine. By integrating a range of materials and employing diverse printing techniques, these approaches address the limitations of single-material and fixed-dimension methods, thereby overcoming the constraints of traditional, uniform complexity. Multimaterial bioprinting fabricates additive manufacturing structures simultaneously with materials vary in composition and mechanical strength, which increases the complexity in biomedical applications. Meanwhile, multidimensional bioprinting involves incorporating additional dimensions (such as time or space) into printing process, which allows for dynamic configuration transformations and functional responses. Here, the basic concepts and components are summarized of multimaterial and multidimensional bioprinting, the medical adaptation is discussed and the advantages, challenges as well as future perspectives of current approaches are analyzed. Moreover, this review provides perspective on multimaterial and multidimensional bioprinting, and highlights new opportunities in regenerative medicine tissue engineering, particularly in bone tissue engineering bioprinting.