Alfrisany Najm Mohsen, Shokati Babak, Tam Laura Eva, De Souza Grace Mendonca
Department of Dental Health, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia.
Faculty of Dentistry, University of Toronto, Toronto, Canada.
J Adv Prosthodont. 2019 Jun;11(3):162-168. doi: 10.4047/jap.2019.11.3.162. Epub 2019 Jun 26.
The aim of this study was to evaluate the effect of occlusal adjustments on the surface roughness of yttria-tetragonal zirconia polycrystal (Y-TZP) and wear of opposing artificial enamel.
Twenty-five Y-TZP slabs from each brand (Lava, 3M and Bruxzir, Glidewell Laboratories) with different surface conditions (Control polished - CPZ; Polished/ground - GRZ; Polished/ground/repolished - RPZ; Glazed - GZ; Porcelain-veneered - PVZ; n=5) were abraded (500,000 cycles, 80 N) against artificial enamel (6 mm diameter steatite). Y-TZP roughness (in µm) before and after chewing simulation (CS) and antagonist steatite volume loss (in mm) were evaluated using a contact surface profilometer. Y-TZP roughness was analyzed by three-way analysis of variance (ANOVA) and teatite wear by two-way ANOVA and Tukey Honest Difference (HSD) (=.05).
There was no effect of Y-TZP brand on surface roughness (=.216) and steatite loss (=.064). A significant interaction effect (<.001) between surface condition and CS on Y-TZP roughness was observed. GZ specimens showed higher roughness after CS (before CS - 3.7 ± 1.8 µm; after CS - 13.54 ± 3.11 µm), with partial removal of the glaze layer. Indenters abraded against CPZ (0.09 ± 0.03 mm) were worn more than those abraded against PVZ (0.02 ± 0.01 mm) and GZ (0.02 ± 0.01 mm). Higher wear caused by direct abrasion against zirconia was confirmed by SEM.
Polishing with an intraoral polishing system did not reduce the roughness of zirconia. Wear of the opposing artificial enamel was affected by the material on the surface rather than the finishing technique applied, indicating that polished zirconia is more deleterious to artificial enamel than are glazed and porcelain-veneered restorations.
本研究旨在评估咬合调整对钇稳定四方多晶氧化锆（Y-TZP）表面粗糙度及对颌人造牙釉质磨损的影响。
从每个品牌（Lava、3M和Bruzir，Glidewell Laboratories）选取25个具有不同表面状况的Y-TZP板（对照抛光 - CPZ；抛光/研磨 - GRZ；抛光/研磨/再抛光 - RPZ；上釉 - GZ；烤瓷贴面 - PVZ；n = 5），与直径6 mm的滑石质人造牙釉质进行摩擦（500,000次循环，80 N）。使用接触式表面轮廓仪评估咀嚼模拟（CS）前后Y-TZP的粗糙度（单位：µm）以及对颌滑石质材料的体积损失（单位：mm）。通过三因素方差分析（ANOVA）分析Y-TZP的粗糙度，通过双向ANOVA和Tukey真实差异（HSD）（α =.05）分析滑石质材料的磨损情况。
Y-TZP品牌对表面粗糙度（P =.216）和滑石质材料损失（P =.064）无影响。观察到表面状况与CS之间对Y-TZP粗糙度存在显著的交互作用（P <.001）。GZ试件在CS后显示出更高的粗糙度（CS前 - 3.7 ± 1.8 µm；CS后 - 13.54 ± 3.11 µm），釉层部分去除。与CPZ摩擦的压头磨损（0.09 ± 0.03 mm）大于与PVZ（0.02 ± 0.01 mm）和GZ（0.02 ± 0.01 mm）摩擦的压头。扫描电子显微镜证实了与氧化锆直接摩擦导致的更高磨损。
使用口腔内抛光系统进行抛光并未降低氧化锆的粗糙度。对颌人造牙釉质的磨损受表面材料而非所应用的修整技术影响，表明抛光后的氧化锆对人造牙釉质的损害大于上釉和烤瓷贴面修复体。
