Enhancing the biocompatibility of additively manufactured Ti-6al-4 V ELI with diamond-like carbon coating

Orthopedic implants provide patients with an opportunity to regain functionality lost from illness, disease, or injury. Recent advancements in additive manufacturing (AM) techniques have allowed for the increased customization of Ti-6Al-4V ELI (extra low interstitials) implants to complement natural variations in the human anatomy. Yet, the low bioactivity of Ti-6Al-4 V ELI and possible adverse effects from the leeching of aluminum and vanadium complicate the post-operation recovery process. In this work, Ti-6Al-4 V ELI samples are printed using the electron beam melt technique in two directions and coated with diamond-like carbon (DLC) to examine whether their biological properties can be improved. By conducting in vitro studies with Saos-2 osteosarcoma cells, the effects of morphology and surface chemistry are correlated to the bioactivities of the coated and uncoated samples. The outcome of the study suggested that DLC coating is a viable method for controlling the surface bioactivity of a material. It indicates that a carbon coating, along with an appropriate topography, has the potential to promote the proliferation and maturity of bone cells and hence enhance the performance of additively manufactured products in next-generation biomedical applications.