Shinohara M S, Rodrigues J A, Pimenta L A
School of Dentistry of Piracicaba, University of Campinas, Piracicaba, São Paulo, Brazil.
Quintessence Int. 2001 May;32(5):413-7.
After bleaching treatment, esthetic restorations often need to be replaced due to color changes. Some papers have shown alterations in the bond of adhesive restorations to bleached teeth. The purpose of this study was to evaluate tooth and resin composite adhesion when submitted to nonvital dental bleaching.
One hundred and twenty bovine teeth were assigned to 3 groups (n = 40); paste of sodium perborate and water; 37% carbamide peroxide gel; and no bleaching (control). After 3 weeks of continuous bleaching treatment, standardized Class V cavities were prepared at the cementoenamel junction and restored with Single Bond adhesive system and Z100 resin composite. The samples were thermocycled 1,500 times (5 +/- 1/55 +/- 1 degrees C) with a 1-minute dwell time. Then, they were immersed in a 2% methylene blue solution (pH 7) for 4 hours, sectioned, and analyzed by stereomicroscopy. Microleakage analyses were done, using scores from 0 to 4, considering leakage on the incisal wall (enamel) and the cervical wall (dentin). Data were analyzed by Kruskal-Wallis and Mann-Whitney tests (alpha = 0.05).
The results showed that sodium perborate and carbamide peroxide gel significantly increase the microleakage in Class V resin composite restorations to dentin but not to enamel margins.
The risk of microleakage in dentin margins is increased soon after bleaching treatment.
漂白治疗后，由于颜色变化，美学修复体常常需要更换。一些论文显示，粘结修复体与漂白牙齿之间的粘结力发生了改变。本研究的目的是评估非活髓牙漂白后牙齿与树脂复合材料的粘结情况。
120颗牛牙被分为3组（每组n = 40）；过硼酸钠与水糊剂组；37%过氧化脲凝胶组；未漂白组（对照组）。连续漂白治疗3周后，在牙骨质釉质界制备标准化Ⅴ类洞，并用单键粘结系统和Z100树脂复合材料进行修复。将样本在5±1/55±1℃下进行1500次热循环，每次保持1分钟。然后，将它们浸入2%亚甲蓝溶液（pH 7）中4小时，切片，并用体视显微镜进行分析。进行微渗漏分析，根据切端壁（釉质）和颈壁（牙本质）的渗漏情况，使用0至4分的评分标准。数据采用Kruskal-Wallis和Mann-Whitney检验进行分析（α = 0.05）。
结果表明，过硼酸钠和过氧化脲凝胶显著增加了Ⅴ类树脂复合材料修复体与牙本质之间的微渗漏，但对釉质边缘无影响。
漂白治疗后不久，牙本质边缘微渗漏的风险增加。
