PhD student, Faculty of Dentistry, The University of British Columbia, Vancouver, Canada; Associate Professor, Department of Prosthodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Former student, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
J Prosthet Dent. 2022 May;127(5):767.e1-767.e7. doi: 10.1016/j.prosdent.2022.01.032. Epub 2022 Mar 11.
Restorations should show low color stainability after clinical and laboratory procedures; however, the impacts of surface treatment and surface region on the color stainability of zirconia restorations are unclear.
The purpose of this in vitro study was to evaluate the effect of surface treatment and surface region on the color stainability of a cemented high-translucency monolithic zirconia ceramic after coffee thermocycling.
Thirty high-translucency Ø10×0.5-mm monolithic zirconia disk specimens were divided into 3 groups based on the surface treatment applied: adjusting (A), polishing (P), and glazing (G). Specimens were cemented to composite resin backings and given 10 000 thermocycles in a coffee solution. CIELab values were measured with a spectrophotometer before and after thermocycling in central and marginal surface regions. ΔE values were calculated and compared with perceptibility (ΔE=0.8) and acceptability (ΔE=1.8) thresholds to interpret the color changes due to coffee thermocycling. Repeated measures ANOVA and Bonferroni tests were used for data analysis (α=.05).
Mean ΔE values ranged between 0.72 and 1.26. The surface treatment significantly affected the ΔE (P=.005); however, the surface region (P=.499) and the interaction of surface treatment and surface region (P=.998) did not affect the ΔE. The mean ΔE values were less than 0.8 for group G, but greater than 0.8 and less than 1.8 for groups A and P.
Glazing provides the lowest color stainability for cemented high-translucency monolithic zirconia, inducing imperceptible color changes after coffee thermocycling.
修复体在临床和实验室操作后应显示低颜色可染性；然而，表面处理和表面区域对氧化锆修复体颜色可染性的影响尚不清楚。
本体外研究的目的是评估表面处理和表面区域对咖啡热循环后黏结高透明度整体氧化锆陶瓷的颜色可染性的影响。
根据所应用的表面处理方法，将 30 个高透明度 Ø10×0.5-mm 整体氧化锆盘试件分为 3 组：调整组（A）、抛光组（P）和上釉组（G）。将试件黏结到复合树脂背衬上，并在咖啡溶液中进行 10000 次热循环。在中央和边缘表面区域进行热循环前后，使用分光光度计测量 CIELab 值。计算 ΔE 值，并与可感知性（ΔE=0.8）和可接受性（ΔE=1.8）阈值进行比较，以解释由于咖啡热循环引起的颜色变化。使用重复测量方差分析和 Bonferroni 检验进行数据分析（α=.05）。
平均 ΔE 值在 0.72 至 1.26 之间。表面处理显著影响 ΔE（P=.005）；然而，表面区域（P=.499）和表面处理与表面区域的相互作用（P=.998）对 ΔE 没有影响。对于组 G，平均 ΔE 值小于 0.8，但对于组 A 和 P，平均 ΔE 值大于 0.8 且小于 1.8。
上釉为黏结高透明度整体氧化锆提供了最低的颜色可染性，在咖啡热循环后引起不可感知的颜色变化。
