The objective was to evaluate the color stability of ceramic veneers luted with resincements and pre-heated composite resins (60 oC) for 12 months, and determine the degreeof conversion (DC) of the luting agents. Two resin cements (AllCem Veneer, light-cured(LRC) and AllCem, dual-cured (DRC)] and three composite resins [Z100 (MNCR–minifilled),Herculite Classic (MHCR–micro-hybrid) and Durafill (MCCR–microfilled)] were used forcementing 0.8-mm-thick lithium-silicate glass-ceramic laminates (Suprinity, shade B2-HT, Vita) on bovine enamel (n=10). The specimens were stored at 37 oC in distilled water.CIELab parameters were determined at 24h after luting (baseline), 7, 30, 90, 180 days and12 months. Three specimens were prepared for DC evaluation, performed by micro-Ramanspectroscopy. Data were analyzed by ANOVA and Tukey’s test (α=5%). For ΔEab and ΔE00,there were significant differences for luting material (p0.001), time (p0.001), and doubleinteraction (p0.001). The groups cemented with MHCR (1 year), MCCR (90 days and 1year) and MCCR-PH (1 year) were the ones with ΔE values greater than the acceptabilitythreshold. All other groups maintained their ΔE lower than the acceptability threshold after1 year in distilled water. Regarding DC, there were no significant differences (p=0.127)among the materials. Non-significant negative correlations were observed between themean ΔEab and DC (R=-0.65) and ΔE00 and DC (R=-0.64). A significant positive correlationwas observed mean ΔEab and ΔE00 (R=0.99). It was concluded that the different lutingagents influenced the final color of the restorations. The heating of the composite resinsdid not affect their DC.
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