3D PRINTING OF A CRANIAL IMPLANT WITH ENERGY-ABSORBING POLYMER VIA ARBURG PLASTIC FREEFORMING TECHNOLOGY

Abstract

Additive Manufacturing (AM) brings ground-breaking opportunities to provide customized healthcare solutions with reasonable time and cost. These benefits become more evident if reducing the distance between the printing process and surgery. In this direction, the Arburg Plastic Freeforming (APF) process offers unprecedented opportunities. The absence of hazardous feedstock materials such as powders allows for the utilization of this technology within hospitals. Also, unlike traditional AM processes, APF makes it possible to process medically approved standard granulates without compromising their certification. In this study, APF has been used to manufacture, for the first time, a patient-specific cranial implant (PSCI) using a biocompatible polymer with a high energy absorption capability, namely, PolyCarbonate Urethane (PCU). The main technological issue was represented by the lack of a solvable support material compatible with PCU. This obstacle was overcome by a custom support structure made of the same material, which can be removed at the end of the process with limited damage to the PSCI. The orientation of the part within the building chamber was chosen to optimize the accuracy of critical features and the surface quality of the regions facing the brain. The 3D-printed cranial implant showed high toughness during mechanical impact tests.