The transition from 3D to 4D printing has revolutionized various domains of healthcare, pharmaceuticals, design and architecture, and coating processes. The evolution from 3D printing to 4D printing has added a fourth dimension as a time-dependent response. This review discusses the significance, demands, various types of smart materials/biomaterials, as well as bioinks and printers used in 4D printing technology. This review also provides insights into the limitations of the bioprinting process and bioinks used in various bioprinting technologies and the challenges that come with these limitations. A brief discussion on the future potential of the fundamentals and capabilities of 4D printing is also discussed.
Keywords: 3D printing; 4D printing; bioprinting; shape memory materials; stimuli-responsive materials.