Surface Modification of Metallic Biomaterials for Orthopaedic Applications

Abstract

Metallic biomaterials such as stainless steel and Co-based alloys are corrosion resistant and possess excellent mechanical properties and hence can be used in load-bearing implants for human tissue repair. However, these materials are bioinert and some of them can cause concerns over their long-term implantation as they release cytotoxic metal ions to surrounding body tissues. Forming a bioactive coating on implantable metals combats these problems and makes these materials very attractive for medical applications. This paper gives an overview of our research work over the past decade on using a number of surface modification techniques (plasma spraying, spraying-and-sintering, ion beam assisted deposition, biomimetic deposition, etc.) to improve the osteoconductivity of metallic biomaterials (Ti, Ti-6Al-4V and NiTi SMA).

Novel Difunctional Reversible Addition Fragmentation Chain Transfer (RAFT) Agent for the Synthesis of Telechelic and ABA Triblock Methacrylate and Acrylate Copolymers

“…Multiple thermal transitions can be seen for both samples, however a well-defined endothermic transition with a corresponding change in the heat capacity of the material at −48 °C is seen for the high molecular weight material. This is in the range of reported glass transition temperatures for poly(butyl acrylate) . The identification in both samples of a glass transition temperature for PMMA at 105 °C, which is consistent with reported values for atactic PMMA, indicates the immiscibility of the two blocks.…”

“…This is in the range of reported glass transition temperatures for poly(butyl acrylate) . The identification in both samples of a glass transition temperature for PMMA at 105 °C, which is consistent with reported values for atactic PMMA, indicates the immiscibility of the two blocks. Some samples also showed small thermal events between −48 and +105 °C, indicating phases of mixed composition coexisting with the phase separated material.…”

Effect of surface grain boundary density on preosteoblast proliferation on titanium

“…Thus, the design of microstructures and surfaces of Ti medical implants has been the focus of research to enhance the integration of Ti with bone tissue [3]. Surface treatments can create desirable nanoscale structures on surface on Ti, as reviewed by Wang, et al [4] and Kunčická, et al [3], but enhancing titanium's strength for load-bearing applications also requires fine-scale volumetric features rather than surface-only modifications. The strength [5], corrosion resistance [6], and cytocompatibility [7,8] of commercial purity (CP) Ti can be enhanced by introducing sub-micron and nanometer-scale microstructural features via Severe Plastic Deformation (SPD) methods to produce ultrafine grain (UG) titanium.…”