Fayad Basma R, Zohdy Maged M, Hussein Ghada A, Farag Engy A
Department of Fixed Prosthodontics, British University, Cairo, Egypt -
Department of Fixed Prosthodontics, British University, Cairo, Egypt.
Minerva Dent Oral Sci. 2024 Apr;73(2):88-95. doi: 10.23736/S2724-6329.23.04761-7. Epub 2023 Apr 17.
The purpose of this study was to compare the color stability and marginal adaption of lithium disilicate veneers before and after thermocycling using various resin composite materials employed as cement.
Laminate veneer preparation was done on an acrylic tooth according to standardized procedures. The veneer preparations were duplicated into twenty-one dies. The veneers were fabricated from lithium disilicate using the CEREC in Lab system. According to the cement type, the twenty-one die specimens were randomly divided into three equal groups: group I, with light cured adhesive resin cement (N.=7), group II, with flowable light cured composite, and group III, with preheated nano filled composite. The cemented specimens underwent 5000 thermocycling cycles. Color was assessed using a reflective spectrophotometer. The vertical marginal gap, following cementation and thermocycling, was measured using a digital microscope. One-way ANOVA followed by Tukey's post-hoc test was used to statistically assess the data.
After thermocycling, there was no statistically significant difference in ΔE among cement type groups for color stability (P=0.369). However, the preheated composite showed the lowest ΔE mean values. Within adhesive resin cement and flowable composite groups, marginal gap means values recorded after thermocycling were significantly higher than those after cementation (P=0.013 and P<0.001, respectively).
Although preheated composite cement showed the highest marginal discrepancy, it would be the best choice regarding color stability.
本研究的目的是比较使用各种树脂复合材料作为粘结剂时，热循环前后二硅酸锂贴面的颜色稳定性和边缘适应性。
按照标准化程序在丙烯酸树脂牙上制作层压贴面。将贴面制作复制到21个代型上。使用CEREC in Lab系统由二硅酸锂制作贴面。根据粘结剂类型，将21个代型标本随机分为三组，每组7个：第一组，使用光固化粘结树脂粘结剂；第二组，使用可流动光固化复合材料；第三组，使用预热纳米填充复合材料。对粘结后的标本进行5000次热循环。使用反射分光光度计评估颜色。使用数字显微镜测量粘结和热循环后的垂直边缘间隙。采用单因素方差分析和Tukey事后检验对数据进行统计学评估。
热循环后，各粘结剂类型组间颜色稳定性的ΔE无统计学显著差异（P = 0.369）。然而，预热复合材料的ΔE平均值最低。在粘结树脂粘结剂组和可流动复合材料组中，热循环后记录的边缘间隙平均值显著高于粘结后（分别为P = 0.013和P < 0.001）。
尽管预热复合材料粘结剂显示出最高的边缘差异，但就颜色稳定性而言，它是最佳选择。
