de Azevedo Cubas Gloria Beatriz, Camacho Guilherme Brião, Demarco Flávio Fernando, Pereira-Cenci Tatiana
Graduate student, Department of Restorative Dentistry, School of Dentistry, Federal University of Pelotas, Brazil.
Eur J Dent. 2011 Jul;5(3):245-52.
The aim of this study was to assess the influence of various ceramic thicknesses and luting agents on color variation in five ceramic systems.
Fifteen disc-shaped ceramic specimens (11 mm diameter; shade A3) were fabricated with each of the six veneering ceramics tested, with 1, 1.5, or 2 mm thickness (n=5). Resin composite discs (Z-250, shade C4) were used as bases to simulate a chromatic background. The cementation of the veneers was carried out with an opaque resin-based cement (Enforce, shade C4), a resin-based cement (Enforce, shade A3), or without cement (C4, control group). Color differences (ΔE*) were determined using a colorimeter. Three-way ANOVA was used to analyze the data, followed by a Tukey post-hoc test (α=.05).
The Lab* values of the ceramic systems were affected by both the luting agent and the ceramic thickness (P<.05). In general, there was no difference between the control group and the group using the resin-based cement. The use of an opaque luting agent resulted in an increase of the color coordinates a*, b*, L*, producing differences in ΔE* values for all ceramics tested, regardless of the thickness (P<.05). For the 2-mm thick veneers, higher values in the color parameters were obtained for all ceramics and were independent of the luting agent used.
The association of 2-mm thickness with opaque cement presented the strongest masking ability of a dark colored background when compared to a non- opaque luting agent and the other thicknesses tested.
本研究旨在评估不同陶瓷厚度和粘结剂对五种陶瓷系统颜色变化的影响。
使用六种测试的饰面陶瓷制作15个圆盘状陶瓷标本（直径11毫米；A3色），厚度分别为1毫米、1.5毫米或2毫米（n = 5）。使用树脂复合圆盘（Z - 250，C4色）作为基底来模拟彩色背景。使用不透明树脂基粘结剂（Enforce，C4色）、树脂基粘结剂（Enforce，A3色）或不使用粘结剂（C4，对照组）对饰面进行粘结。使用色差仪测定颜色差异（ΔE*）。采用三因素方差分析对数据进行分析，随后进行Tukey事后检验（α = 0.05）。
陶瓷系统的Lab值受粘结剂和陶瓷厚度的影响（P < 0.05）。一般来说，对照组和使用树脂基粘结剂的组之间没有差异。使用不透明粘结剂会导致颜色坐标a、b*、L增加，无论厚度如何，所有测试陶瓷的ΔE值都会产生差异（P < 0.05）。对于2毫米厚的饰面，所有陶瓷的颜色参数值都较高，且与所使用粘结剂无关。
与不透明粘结剂和其他测试厚度相比，2毫米厚度与不透明粘结剂的组合对深色背景具有最强的遮盖能力。
