Geometric Evaluation of Biomimetic 3D Printed Rat Femur

Total knee replacements (TKR) of Titanium (Ti), Ti6Al4V (Ti64) and CoCrMo (CoCr) alloys have exhibited post implantation life spans extending over 15 years; however, their use is limited by loosening, metal wear particle or stress-related bone resorption and mechanical failures. Recently, with the advent of personalized, and patient-specific manufacturing technologies; implant components can be additive manufactured, and the integration of biological and mechanical methods are able to improve clinical long-term compatibilities. The primary aim of this present study is to evaluate the geometrical accuracy of an AM-native and mesh structured rat-femur used by various biocompatible metal. The femurs were scanned using micro scaled computed tomography (micro-CT) and a designed mesh structure. In this study, 3D printing data optimization was performed within the transplant tolerance through finite element analysis between image data, 3D scan data, and 3D printed output from rat femur for biomimetic 3D printing optimization. Through 3D printing using CoCr, pure titanium, and Ti64 alloy, we tried to explore the optimal implanted metal material and design with less morphological error. The materials and implant designs with conditions more similar to those of actual bones were selected for implantation of patient-specific implants, and 3D printing process was applied to post-traumatic fracture repair.