Pre-processing and Preparation of Medical 3D Printed Parts

The workflow for medical 3D printing is complex, and it involves multiple steps. After segmentation and computer aided design (CAD), the final anatomic representation for the 3D printed parts (e.g., anatomic models and/or guides) must be prepared for 3D printing. The surface mesh such as a STL file must be watertight and have no self-intersecting elements or shells; these terms are introduced and explained in this chapter. Additionally, print preparation software is introduced to the workflow. In this step, the STL file is oriented and optimally supported to achieve the best 3D printing outcome. The orientation step greatly impacts the delicate features of the part, since support removal can damage part features. As a general rule, the more delicate surfaces/features should face away from the build plate. The location on the build plate also impacts the outcome metrics including the print accuracy and precision. The print parameters must be defined based on the material, desired accuracy, and expected turnaround time. This chapter reviews print preparation across the material extrusion (MEX), vat photopolymerization (VP), and material jetting (MJT) technologies because they are the commonly used 3D printers in healthcare facilities.