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Biomaterials in TMJ replacement873the biocompatibility and toxicity of these newer elements is needed.(48,59,68) To overcome the problem of wear, several approaches have been studied, such as reinforcing the matrix with hard precipitates, heat treatment, surface modifications, and laser 3D-printing. Yet increasing the wear resistance of Ti alloys remains a challenge. While Samuel et al.(71) found that the addition of hard ceramic phases, such as boride (B), might enhance wear resistance, research by Majumdar et al.(72) indicated that adding TiB to the matrix of a β-Ti alloy led to deterioration of the wear properties and less attachment of human osteoblast-like MG-63 cells to the material, compared with non-reinforced alloys.(73) As of now, no perfect technique has been found to increase the wear resistance of β-Ti alloys. Studies conducted by Kopova et al.(69), reinforcing the β-Ti alloy matrix with Fe and Si, have shown positive results. These authors reported improvement in both mechanical and biological properties and concluded that Ti-35Nb-7Zr-6Ta-2Fe-0.5Si might be suitable for orthopedic implantation. However, they did not mention the wear resistance of this material. Recent research by Chan et al.(68) using laser surface treatment with a continuous wave fiber laser has also shown promising results, producing better wear resistance and corrosion resistance than untreated TNZT.Surface modificationsWhile altering the alloy composition of Ti to prevent the release of potentially toxic metal ions, such as Al and V, is a valuable approach to improving its biocompatibility, an alternative method is to modify the implant’s surface. As discussed earlier, a biomaterial’s surface can be a decisive factor determining its long-term success. Extensive research efforts have been focused on surface modifications of Ti, either by triggering an appropriate cell response to improve osseointegration or by hindering bacterial attachment to limit infection rates. There are a wide variety of surface modification strategies described in the literature, including techniques to alter the surface topography, as well as the chemical composition, of the surface. For a comprehensive overview of the various surface modifications available and under investigation to date, the reader is referred to several outstanding review papers.(74–76)Nikolas de Meurechy NW.indd 87 05-06-2024 10:14