<scp>3D</scp>/<scp>4D</scp>Printing in Additive Manufacturing: Process Engineering and Novel Excipients

Abstract

In recent years, additive manufacturing, which is more colloquially referred to as three-dimensional (3D) printing, has seen high-impact implementation in manufacturing applications in areas such as aeronautics, robotics, electronics, industrial goods, and even the food industry. This chapter introduces the basic concepts of 3D and four-dimensional (4D) printing technologies as they pertain to biomedical applications. 3D printing typically begins with a computer-aided design file that describes the geometry and size of the objects to be printed. 4D printing is defined as printing of 3D objects with the ability to change the former function under the influence of external stimuli over time. The essential difference between 4D printing and 3D printing is the addition of smart design, or responsive materials, that results in a time-dependent deformation of the object. There are only few major technologies used for biomedical printing. These include extrusion-based, droplet-based, and laser-based systems to print the material.