Functionally Graded Porous Implants Obtained by Additive Manufacturing

Porous structures have an increasing use in the biomedical industry due to their advantage, such as supporting tissue regeneration for implants and prostheses used in the body, eliminating stress shielding and aseptic loosening problems. Although porous structures with homogeneous density contributed positively to biological processes, these structures were insufficent to exhibit the desired mechanical properties. The implant to be used in this case should offer the optimum design both biologically and mechanically. In order to solve this problem, functionally graded structures which provide the harmony of tissue regeneration and mechanical behaviour on the load bearing orthopedic implant are presented. The design where porosity is very dense in the load-bearing sections of the implant and less dense in the areas in contact with the tissue have become feasible by the additive manufacturing methods. In this study, the recent developments in the literature on porous implants, functionally graded porous structures and additive manufacturing applications of these structures have been compiled. As a result, a procedure is presented on porous implant designs that will be used to improve mechanical properties by accelerating biological healing processes in additive manufacturing applications.