Ahed M Al-Wahadni, BDS, MDSC, PhD (Clin), FFDRCSI, FDSRCPSG, professor of prosthodontics, Faculty of Dentistry, Jordan University of Science and Technology, Irbid, Jordan.
Ahmad M Abu Al-Addous, BDS, MClinDent, specialist prosthodontist, Private Dental Practice, Amman, Jordan.
Oper Dent. 2022 May 1;47(3):330-336. doi: 10.2341/20-213-L.
To evaluate color changes in milled feldspathic porcelain laminate veneers following hydrofluoric acid etching (HFA), sandblasting (SB), or Er:YAG laser irradiation (LI).
Disc-shaped specimens (thickness=1 mm, diameter=8 mm) were milled from feldspathic porcelain blocks (n=40). Glazed specimens were randomly assigned to four subgroups (n=10 each) according to surface treatment: negative control, HFA, SB, and LI. A layer of translucent, light-cured resin cement (thickness=0.1 mm) was then applied following silanization. The color was characterized by the L*, a*, and b* uniform color space (CIE) using a reflection spectrophotometer. CIEDE2000 (ΔE00) was calculated to determine the color difference between each surface treatment and negative control groups. Data were statistically analyzed using analysis of variance (ANOVA), Kruskal-Wallis, and Dunn-Bonferroni post hoc tests.
There were no significant differences in CIEL* and CIEb* coordinates between negative control and all surface treatment groups (p≥0.108). The SB group demonstrated significantly lower mean CIEa* (higher greenish hue) compared to other groups (p≤0.003). HFA exhibited significantly higher CIEa* (closer to red) when compared to LI (p=0.039). LI induced the smallest overall color change compared to negative control (ΔE00=1.43 [1.07]). However, the differences in ΔE00 values were not statistically significant (p=0.648).
The tested surface treatments did not affect the lightness or the yellowness of the 1-mm-thick milled feldspathic porcelain veneers. However, sandblasting resulted in a significant increase in the greenish hue. The Er:YAG laser resulted in the closest ΔE00 (1.43) to the 50:50% perceptibility threshold (ΔE00=1.2).
评估氢氟酸蚀刻（HFA）、喷砂（SB）和铒：钇铝石榴石激光照射（LI）对铣削长石质瓷贴面的颜色变化。
从长石质瓷块中铣制出厚度为 1 毫米、直径为 8 毫米的圆盘形试件（n=40）。根据表面处理方法，将上釉的试件随机分为四组（每组 n=10）：阴性对照组、HFA 组、SB 组和 LI 组。然后，在硅烷化后用一层半透明、光固化树脂水泥（厚度为 0.1 毫米）。使用反射分光光度计，用 L*、a和 b均匀颜色空间（CIE）对颜色进行特征描述。计算 CIEDE2000（ΔE00）以确定每个表面处理组与阴性对照组之间的颜色差异。采用方差分析（ANOVA）、Kruskal-Wallis 和 Dunn-Bonferroni 事后检验对数据进行统计学分析。
阴性对照组与所有表面处理组的 CIEL和 CIEb坐标无显著差异（p≥0.108）。与其他组相比，SB 组的平均 CIEa*（更绿的色调）显著较低（p≤0.003）。与 LI 相比，HFA 表现出显著更高的 CIEa*（更接近红色）（p=0.039）。LI 与阴性对照组相比，引起的总体颜色变化最小（ΔE00=1.43[1.07]）。然而，ΔE00 值的差异无统计学意义（p=0.648）。
所测试的表面处理方法对 1 毫米厚的铣削长石质瓷贴面的亮度或黄度没有影响。然而，喷砂处理导致绿色调显著增加。铒：钇铝石榴石激光处理导致最接近 50:50%可察觉阈值（ΔE00=1.2）的ΔE00（1.43）。
