Surface Modification of Porous Orthopedic Medical Implants Produced by Additive Manufacturing

Abstract The emergence of additive manufacturing has promoted the preparation of complex porous implants, endowed medical porous implants with better mechanical properties, reduced stress shielding effect, and facilitated the integration of implants with bone tissues. However, the functionalization of medical porous implants still needs to be strengthened. Surface modification can alter surface morphology or load form composition of the material, endow the material with good biological functions such as osteogenesis and antibacterial, and mechanical properties, which is of great significance to improving the safety and effectiveness of the material. Unlike bulk materials, porous implants have complex internal structures, and their modification is mostly performed in fluid (liquid, gas) media to achieve good internal structure encapsulation. This article briefly introduces additive manufacturing technologies of different types of materials, analyzes the characteristics of different molding processes and the existing surface problems, classifies the modification methods according to surface modification principle and the nature of the components, and summarizes the advantages and disadvantages of different modification methods and influencing factors, with aim to provide new ideas for the surface modification of additively manufactured medical porous implants.