Prospects in innovative manufacturing technology of UHMWPE for prostheses and comparison with medical grade UHMWPE

Due to its properties like high load-bearing capacity, biocompatibility, excellent abrasion resistance and strength, ultra-high molecular weight polyethylene (UHMWPE) is widely used as a bearing material in the field of joint prostheses. Currently, UHMWPE is produced by compression molding, ram extrusion or sintering, followed by post-processing techniques, such as milling or machining to finalize the prosthesis geometry and to achieve the final tolerances. With post-processing techniques we are wasting a high cost material, energy and time. In this paper, we collected manufacturing technologies that has have the potential to be used for creating prosthesis with one step production, minimalize material loss and with a view to providing customized manufacturing capabilities. We compared three technologies: (i) ram extrusion (currently used technology for joint prosthesis), (ii) FDM printing and (iii) injection molding. In addition to the feasibility, we focus on the investigation of mechanical properties. Three tests were performed on the manufactured specimens: hardness measurement, tensile test and scanning electron microscope (SEM) to compare the finished parts produced by the different processing technologies.