Tailoring of implant surfaces for enhanced cell performance by micron-MIM

Bone implant integration is particularly influenced by the implant surface topography which consequently determines the long-term stability of the implant. In recent years it has been suggested that topological structures have a great impact on implant stability. This study focuses on processing implant materials with defined surface patterns to directly modulate cell behaviour at the tissue-implant interface. Metal parts made of a biocompatible stainless steel (316L) as test material were produced by micro metal injection moulding (micro-MIM), thereby using hybrid nano / micro powder mixtures. The material was moulded to coin shaped specimens with defined hemispheric surface structures. Depending on process parameters, including nano powder share and sintering temperature, analysis of grain structures and surface topography were performed. Results showed that the use of metal nano powders induced additional sub-micrometer topography on top of the hemispheric structures, providing a positive effect on cell adhesion as compared to non-structured surfaces. Initial results for titanium samples will be presented, too.