Abstract

With the popularity of dental bleaching, the need of immediate restoration following bleaching is increasing urgently. This study aimed to seek methods to improve the bonding strength to enamel of composite resin after bleaching. The best concentration and reaction time of Epigallocatechin gallate (EGCG) regarding bonding strength after bleaching were determined using micro tensile bond strength test (µTBS) to enamel. Bovine Incisors were randomly divided into six groups. Composite resin was built-up after different pretreatments (deionized water, 10% sodium ascorbate, the remineralization fluid, EGCG of the optimal concentration and 75% ethanol) for 1 h after bleaching. µTBS and scanning electron microscopy (SEM) were used to evaluate the effect to immediate bonding strength after bleaching. The mode of failure was determined by a stereo-microscope at 50-fold magnifications. Treatment with 10% EGCG for 30 mins was selected as the best concentration and reaction time. Bleaching led to significantly reduced shear bond strength (p < 0.05). 10% EGCG produced higher µTBS than other groups (p < 0.05). The resin tags after treatments with the four pretreatments were significantly longer and thicker than the control groups under SEM. The application of 10% EGCG could rescue the resin-enamel bond strength after bleaching.

摘要

随着牙齿漂白的普及，漂白后立即修复的需求日益增加。本研究旨在寻求提高漂白后复合树脂与搪瓷结合强度的方法。表没食子儿茶素没食子酸酯 (EGCG) 在漂白后结合强度的最佳浓度和反应时间是使用微拉伸结合强度测试 (μTBS) 确定的。牛门牙随机分为六组。复合树脂经过不同的预处理（去离子水、10%抗坏血酸钠、再矿化液、最佳浓度EGCG和75%乙醇）漂白后1小时后合成。µTBS 和扫描电子显微镜 (SEM) 用于评估漂白后对即时粘合强度的影响。失效模式由放大 50 倍的立体显微镜确定。选择10%EGCG处理30分钟作为最佳浓度和反应时间。漂白导致剪切粘合强度显着降低（p  < 0.05)。10% EGCG 比其他组产生更高的 µTBS ( p  < 0.05)。在扫描电镜下，经过四种预处理后的树脂标签明显比对照组更长更厚。10% EGCG 的应用可以挽救漂白后的树脂-搪瓷结合强度。