Effect of various beverages on color stability of resin cements

The purpose of this in vitro study was to investigate the effects of various staining solutions on the color of resin cements. 4 commercially available resin cements (Rely-X Ultimate Clicker Dual-Cured, Rely-X Veneer Light-Cured, NX-3 Dual-Cured, NX-3 Light-Cured) were tested. The specimens were immersed in 5 different solutions: cola, tea, coffee, red wine as test groups and distilled water as the control group. Before immersion, the initial color value of each specimen was recorded by using a spectrophotometer. Color changes (ΔE) were determined after 24 hours, 72 hours, 144 hours, 216 hours, and 288 hours of immersion. The CIE L*a*b*color space was used to identify color differences. At the end of 288 hours of immersion, the greatest color change (ΔE) was observed for the NX-3 dual-cured resin cement group immersed in red wine (ΔE=21.66±2.73); and the lowest ΔE value was seen when the NX-3 light-cured resin cement group was immersed in cola (ΔE=1.86±0.33). In all resin cement groups, red wine and coffee caused the highest the amount of staining and caused clinically marked color change starting from 24 hours immersion, whereas tea caused marked color change following 72 hours of immersion (NBS>3). All the specimens immersed in distilled water and cola did not show clinically marked discoloration. The effect of time, material, and solution factors on color stability levels of resin cements were significant. As the immersion time increased, the degree of discoloration of all resin cements also increased. The light-cured resin cements were generally more color stable than the dual-cured resin cements. Keywords: Resin cements, color stability, staining, spectrophotometer.