Color Stability of Ceramic Veneers Luted With Resin Cements and Pre-Heated Composites: 12 Months Follow-Up

Abstract The objective was to evaluate the color stability of ceramic veneers luted with resin cements and pre-heated composite resins (60oC) for 12 months, and determine the degree of 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 for cementing 0.8-mm-thick lithium-silicate glass-ceramic laminates (Suprinity, shade B2-HT, Vita) on bovine enamel (n=10). The specimens were stored at 37oC in distilled water. CIELab parameters were determined at 24h after luting (baseline), 7, 30, 90, 180 days and 12 months. Three specimens were prepared for DC evaluation, performed by micro-Raman spectroscopy. Data were analyzed by ANOVA and Tukey’s test (a=5%). For ΔEab and ΔE00, there were significant differences for luting material (p<0.001), time (p<0.001), and double interaction (p<0.001). The groups cemented with MHCR (1 year), MCCR (90 days and 1 year) and MCCR-PH (1 year) were the ones with ΔE values greater than the acceptability threshold. All other groups maintained their ΔE lower than the acceptability threshold after 1 year in distilled water. Regarding DC, there were no significant differences (p=0.127) among the materials. Non-significant negative correlations were observed between the mean ΔEab and DC (R=-0.65) and ΔE00 and DC (R=-0.64). A significant positive correlation was observed mean ΔEab and ΔE00 (R=0.99). It was concluded that the different luting agents influenced the final color of the restorations. The heating of the composite resins did not affect their DC.

摘要 本研究旨在评估经树脂水门汀（resin cements）及60℃预加热复合树脂（pre-heated composite resins）粘接的陶瓷贴面（ceramic veneers）在12个月内的颜色稳定性，并测定粘接剂（luting agents）的双键转化率（degree of conversion, DC）。本研究采用两种树脂水门汀[光固化型AllCem Veneer（LRC）与双固化型AllCem（DRC）]以及三种复合树脂[Z100（MNCR-微填料型）、Herculite Classic（MHCR-微混合填料型）与Durafill（MCCR-微填料型）]，将厚度为0.8mm的硅酸锂玻璃陶瓷贴面（Suprinity，色号B2-HT，Vita出品）粘接于牛牙釉质（bovine enamel）样本上（每组n=10）。所有样本均置于37℃蒸馏水中储存。分别于粘接后24小时（基线）、7天、30天、90天、180天及12个月测定CIELab色空间参数（CIELab parameters）。另制备3个样本用于显微拉曼光谱法（micro-Raman spectroscopy）测定DC。数据采用方差分析（ANOVA）与Tukey检验（Tukey’s test）进行统计学分析（α=5%）。对于ΔEab与ΔE00两种色差值，粘接材料（p<0.001）、时间因素（p<0.001）以及二者的交互作用（p<0.001）均存在显著差异。其中采用MHCR粘接的组别（1年时）、MCCR粘接的组别（90天及1年时）以及MCCR-PH粘接的组别（1年时），其ΔE值高于可接受阈值（acceptability threshold）；其余所有组别在蒸馏水中储存1年后，ΔE值均低于可接受阈值。关于DC，不同材料间未发现显著差异（p=0.127）。平均ΔEab与DC之间（R=-0.65）以及ΔE00与DC之间（R=-0.64）均未呈现显著负相关；而平均ΔEab与ΔE00之间则存在显著正相关（R=0.99）。本研究结论为：不同粘接剂会影响修复体的最终颜色；复合树脂的预加热处理不会影响其双键转化率。