3D and 4D Printing of Biomedical Materials (BMMs)

Abstract

Three-dimensional (3D) printing, or additive manufacturing (AM), is a novel technology that fabricates materials on a print bed layer-by-layer. AM manufactures objects with simple to complex geometries using computer-aided design (CAD) models. AM can process various materials, such as polymers, hydrogels, ceramics, glass, metals, and other composites Four-dimensional (4D) printing is considered the next-generation advancement of AM technology, adding a fourth dimension as the time-dependent shape/functional change after printing. 4D printing processes smart materials capable of changing the shape or function upon exposure to certain stimuli such as humidity, temperature, light, pH of the medium, solvent, and magnetic and electric fields. Shape memory polymers (SMPs) play a key role in this context. AM technologies involved in 4D printed BMMs are mainly direct ink write (DIW), SLA, and multi-MJ, targeting applications in tissue engineering, drug delivery, medical devices, and diagnostics. BMMs are broadly defined as biomaterials manufactured or processed to be utilized as medical devices or related components.