3D printing in biomedical engineering: Processes, materials, and applications

Three-dimensional (3D) printing as a powerful manufacturing platform has been increasingly used in biomedical engineering over the past two decades. Such technologies greatly improve our ability to fabricate a variety of complex and customized biomedical products accurately, efficiently, economically, and with high reproducibility through layer-by-layer positioning of materials, biomolecules, or even living cells in the products. Despite the impressive progress of 3D printing in biomedical engineering, more and greater efforts are needed to develop new and much improved biomedical products via 3D printing. In particular, many challenges in 3D printing processes, materials, and applications must be addressed in order to make available high-quality products and novel products to millions of patients. Addressing these challenges requires the integration of advances in physics, materials science, engineering, biological sciences, and medicine. In this article, we provide a comprehensive and up-to-date review of 3D printing and its applications in the biomedical field. We systematically present and discuss 3D printing technologies, materials, cells, and applications that are associated with biomedical engineering. Additionally, 4D printing and bioprinting are reviewed. We give our analysis and put forward our views on the challenges for 3D printing in biomedical engineering and also possible future developments. It is apparent that 3D printing plays a more and more important role in biomedical engineering and can create a diverse range of high-value biomedical products. This comprehensive review can help to understand the current status and identify future directions of 3D printing in biomedical engineering, as well as moving 3D printing toward manufacturing newer and better biomedical products.