Department of Restorative and Cosmetic Dentistry, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran.
Student Research Committee, Mashhad University of Medical Sciences, Mashhad, Iran.
BMC Oral Health. 2024 Aug 14;24(1):942. doi: 10.1186/s12903-024-04656-1.
This study compared the effectiveness of several techniques in restoring compromised bonding to recently bleached enamel.
Seventy-five healthy bovine incisors were divided into five groups (n = 15). Fifteen teeth (Group 1) remained intact, whereas 60 (Groups 2 to 5) underwent at-home bleaching with 16% carbamide peroxide. The bonding procedures were as follows: Group 1: Bonding of resin composite to unbleached enamel; Group 2: Bonding immediately after bleaching; Group 3: Application of a 10% sodium ascorbate solution for 10 min before bonding; Group 4: Enamel removal to the depth of 0.5 mm; and Group 5: Increased curing time of the bonding agent to 80 instead of 20 s. After 24 h, the specimens were subjected to micro-shear testing, and the failure mode was determined.
ANOVA revealed a significant difference in bond strength among the groups (P < 0.001). The mean bond strength was significantly lower in group 2 than in other groups (P < 0.05), which showed comparable bond strength to each other (P > 0.05). Adhesive failure was the most predominant failure type in all groups. The mixed failure occurred with a frequency of 26.7% in groups 3 and 5. The Fisher's exact test revealed a significant difference in failure modes among the groups (P = 0.047).
The three experimental procedures used in this study, including the application of 10% sodium ascorbate before bonding, enamel removal to the depth of 0.5 mm, and increasing the curing time of the bonding agent to 80 s, were effective in restoring the compromised bonding to recently bleached enamel.
本研究比较了几种技术在恢复近期漂白牙釉质受损粘结的效果。
将 75 颗健康的牛切牙分为五组（n=15）。15 颗牙（第 1 组）保持完整，而 60 颗牙（第 2 至 5 组）在家中用 16%过氧脲进行漂白。粘结程序如下：第 1 组：粘结树脂复合材料到未漂白的牙釉质；第 2 组：漂白后立即粘结；第 3 组：粘结前用 10%抗坏血酸钠溶液处理 10 分钟；第 4 组：去除牙釉质至 0.5mm 深度；第 5 组：将粘结剂的固化时间从 20 秒增加到 80 秒。24 小时后，对标本进行微剪切试验，确定失效模式。
方差分析显示各组间粘结强度有显著差异（P<0.001）。第 2 组的平均粘结强度明显低于其他组（P<0.05），但彼此间粘结强度相当（P>0.05）。所有组中最主要的失效类型均为粘结失败。第 3 组和第 5 组混合失效的频率为 26.7%。Fisher 确切检验显示各组失效模式有显著差异（P=0.047）。
本研究使用的三种实验程序，包括粘结前应用 10%抗坏血酸钠、去除牙釉质至 0.5mm 深度以及将粘结剂的固化时间增加到 80 秒，均可有效恢复近期漂白牙釉质的受损粘结。
