Page 148 - Demo

Chapter 5146with the coated condyle it was 0.67 ± 0.28 mm. The difference between these two groups was not statistically significant (p = 0.3765, t-test). When converted to human mastication habits, these values are equivalent to 0.04 ± 0.02 mm respectively 0.03 ± 0.01 mm per year (Tables 1-3). An average volume loss of 45.85 ± 22.01mm³ could be observed for the UHMWPE articulated with the non-coated Ti6Al4V condyle surface as compared to 25.29 ± 11.43 mm³ when articulated with the coated condyles. The difference was not statistically significant (p = 0.1448; t-test). Based on these results, the amount of volumetric wear translates to 2.08 ± 1.00 resp. 1.15 ± 0.52 mm³/year of human mastication. Table 1: Quantitative results of the damage analysis on explanted components of the custom TMJ TJR. For the UHMWPE fossa component, linear and volumetric wear were determined by 3D scanning and laser line scanning. For the Ti6Al4V condylar surface, surface roughness was assessed using 3D non-contact profilometry. Prostheses incorporating a non-coated Ti6Al4V condyle or a H-DLC-coated Ti6Al4V condyle are compared. Values represent mean ± standard deviation.Non-coated Ti6Al4V condyleH-DLC-coated Ti6Al4V condyleLinear wear of UHMWPE fossaMax wear (mm) 0.88 ± 0.41 0.67 ± 0.28Maximal wear/year in sheep (mm/year) 1.11 ± 0.53 0.85 ± 0.35Maximal wear/year in humans (mm/year) 0.04 ± 0.02 0.03 ± 0.01Volumetric wear of UHMWPE fossaTotal wear (mm³) 45.85 ± 22.01 25.29 ± 11.43 Wear/year in sheep (mm³/y) 58.17 ± 27.95 32.04 ± 14.49Wear/year in humans (mm³/y) 2.08 ± 1.00 1.15 ± 0.52Roughness of Ti6Al4V condyleSa (µm) 2.40 ± 2.08 * 0.69 ± 0.07 *Sq (µm) 3.47 ± 3.01 * 0.90 ± 0.08 *Ra (µm) 0.28 ± 0.17 * 0.12 ± 0.04 *Rt (µm) 1.91 ± 1.23 * 0.65 ± 0.27 *Sa = average roughness, the arithmetic mean of the absolute values of the surface departures from the mean plane within the sampling areaSq = root mean square height, the root mean square value of the surface departures within the sampling areaRa = average roughness, the arithmetic average of the absolute values of the heights of the assessed profilesRt = maximum height of the profile, the vertical distance between the highest and lowest points of the assessed profiles* Statistically significant difference between coated and non-coated condylesNikolas de Meurechy NW.indd 146 05-06-2024 10:14