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Chapter 13346human or animal trials, this issue should be corrected. This correction would also enable improvements to the best-fit algorithm by preselecting a series of reference points for each fossa component, thereby enhancing the accuracy of the analysis data. Additionally, although no significant difference in wear was observed between the coated and uncoated systems, a post hoc power analysis revealed that this was due to an insufficient sample size. While financial and ethical considerations limited our total sample size, this must be taken into account in future research.Important to remark is that a displacement of the fossa component was seen in 3 of the sheep. This displacement was most likely due to the use of 2mm diameter fixation screws for the fossa component, as determined for human subjects, despite the fossa being subjected to more laterotrusive movement in the sheep. This might have led to excessive stress in the bone surrounding the screws, with gradual bone resorption and thus micromovement of the fossa component, resulting in this displacement.(96–98) However, after removal of these three results, both the average linear and volumetric wear remained well within the acceptable range.(95) A high surface roughness (Ra 0.2-0.63 µm) can increase the amount of wear of the opposing articular surface and lead to larger wear particles. For this reason, an industry standard for the surface smoothness of metallic and ceramic articulating surfaces in both knee (ISO 7207-2) and hip prostheses (ISO 7206-2) at the point of implantation (Ra ≤0.1 µm, Ra 0.05-0.02 µm) has been established. This is not the case for TMJR.(4,99–102) In order for this custom-made total TMJR to meet orthopedic standards, a polishing protocol was established within the HadSat®-protocol, to obtain a Ra ≤0.1 µm, as is the standard for a total knee prosthesis. A pristine DLC-coated sample was analyzed using confocal laser microscopy analysis, revealing a surface roughness (Ra) of 0.09 µm. A confocal laser microscopy analysis of the uncoated condyles after explantation revealed a mean Ra of 0.28 µm ± 0.17 µm (Sa of 2.40 µm ± 2.08 µm), thus risking an increase in amount of wear of the opposing articulating surface. In comparison, the coated condyles revealed a mean Ra of 0.12 µm ± 0.04 µm (Sa of 0.69 µm ± 0.07 µm) which was not only Nikolas de Meurechy NW.indd 346 10-06-2024 11:12