Improvement of Tribological and Biocompatibility Properties of Orthopedic Materials Using Piezoelectric Direct Discharge Plasma Surface Modification.

Various types of alloys and polymers are utilized in orthopedic implants. However, there are still several issues accompanied by the use of prosthetic materials, such as low wear performance and catastrophic failure. Surface enhancement of biomaterials is a promising method that can improve the success rate of prosthetic operations without negatively affecting their bulk properties while improving the biocompatibility of implants and reducing infections. Nonthermal plasma treatment has become a ubiquitous surface modification method in sterilization and healthcare applications. However, the clinical applications of such an approach have been limited due to the lack of detailed studies delineating the wear behavior and biocompatibility of implants after plasma treatment. In this study, we have employed a handheld piezoelectric direct discharge (PDD) plasma generator to modify the surface of two common metallic (Ti6Al4V) and nonmetallic (GUR1020 polymer) biomaterials used typically in joint and disc replacements. We have observed an approximately 60-fold reduction in tribological wear rate along with a 2- to 3-fold increase in the biocompatibility properties of plasma coated samples compared to noncoated (untreated) surfaces, respectively. Our study introduces a novel application of nonthermal PDD plasma technology that is capable of increasing the quality and success rate of joint and disc replacements.