Influence of resin cement shade on the color and translucency of ceramic veneers

Abstract

Objective This in vitro study evaluated the effect of two different shades of resin cement (RC- A1 and A3) layer on color change, translucency parameter (TP), and chroma of low (LT) and high (HT) translucent reinforced lithium disilicate ceramic laminates.Material and Methods One dual-cured RC (Variolink II, A1- and A3-shade, Ivoclar Vivadent) was applied to 1-mm thick ceramic discs to create thin RC films (100 µm thick) under the ceramics. The RC was exposed to light from a LED curing unit. Color change (ΔE) of ceramic discs was measured according to CIEL*a*b* system with a standard illuminant D65 in reflectance mode in a spectrophotometer, operating in the light range of 360-740 nm, equipped with an integrating sphere. The color difference between black (B) and white (W) background readings was used for TP analysis, while chroma was calculated by the formula C* ab=(a*2+b*2)½. ΔE of 3.3 was set as the threshold of clinically unacceptable. The results were evaluated by two-way ANOVA followed by Tukey's post hoc test.Results HT ceramics showed higher ΔE and higher TP than LT ceramics. A3-shade RC promoted higher ΔE than A1-shade cement, regardless of the ceramic translucency. No significant difference in TP was noted between ceramic discs with A1- and those with A3-shade cement. Ceramic with underlying RC showed lower TP than discs without RC. HT ceramics showed lower chroma than LT ceramics, regardless of the resin cement shade. The presence of A3-shade RC resulted in higher chroma than the presence of A1-shade RC.Conclusions Darker underlying RC layer promoted more pronounced changes in ceramic translucency, chroma, and shade of high translucent ceramic veneers. These differences may not be clinically differentiable.

Translucency and color stability of resin composite and dental adhesives as modeling liquids – A one-year evaluation

“…Here, we used the CIE L * a * b * system to evaluate ΔE * . Although some recent studies have demonstrated that another measurement system, i.e., CIEDE2000, may provide a better fit than the former in the evaluation of color difference thresholds, 10,18,19,20 many other studies use the CIE L*a*b* color system to analyze color outcomes in dentistry 3,5,21,22,23 because this system features predictability and clinical importance. ΔE * did not increase after 12 months of storage in specimens prepared with the modeling liquids.…”

Optical properties of contemporary monolithic CAD‐CAM restorative materials at different thicknesses

“…23 The optical properties of restorative materials are significantly influenced by the material structure [24][25][26][27] and thickness. 24,25,[27][28][29][30] In addition, several studies have examined the factors that can affect the optical properties of dental restorative materials, including shade, 25,31 manufacturing technique, 22,26 luting agent, 30,32,33 background shade, 34,35 surface texture, 36,37 and illuminants. 24,38 This study aimed to evaluate the translucency and opalescence of current monolithic CAD-CAM restorative materials with different chemical compositions and thicknesses.…”

Evaluation of the Final Color of Ceramic Veneers with Different Self-Adhesive Resin Cements

“…Previous studies state that high translucent ceramics have approximately the same translucency parameters as enamel [19]. Due to this similarity, prediction of CV translucency parameters should be done according to the use of these cements under the veneer and the interaction between ceramic, cement and teeth occur.…”

“…Therefore, the selection of the substrate that is most related to the clinical conditions is considered. Nonetheless, standardization of the color and surface properties of substrate is difficult, most research studies used composite substrate [5,9,10,13] or no substrate [4,19,21]. Some studies used human molar [3,17] or bovine teeth [2] to stimulate clinical conditions.…”