湿度对"单瓶"牙本质粘结系统微拉伸粘结强度的影响

目的用微拉伸强度检测法评价脱矿牙本质表面的不同"湿度"状态对酒精/水基和丙酮基"单瓶"牙本质粘结系统粘结强度的影响.方法选择40颗健康前磨牙,去除牙合面釉质,随机均分为8个实验组,在过湿、用滤纸吸干、用空气干燥1 s或用空气干燥30 s的脱矿牙本质上分别应用Single Bond或Prime&Bond NT单瓶牙本质粘结系统.将牙齿片切为粘结面积约0.9 mm×0.9 mm的长方体状样本,进行微拉伸粘结强度检测,对结果进行统计学分析.结果对于同一种粘结系统,其吸干组和1 s干燥组间的微拉伸粘结强度值无统计学差异,但均显著高于过湿组和30 s干燥组.结论脱矿牙本质表面的湿度对酒精/水基和丙酮基"单瓶"牙本质粘结系统的粘结强度有极大的影响.

Effects of Residual Water on Microtensile Bond Strengths of Single-Bottle Adhesive Systems to Dentin

Objective: To determine the effects of different dentin surface moisture on the microtensile bond strengths of an ethanol/water-based and an acetone-based adhesive systems. Methods: 40 intact human premolars extracted for orthodontic reasons were used. Superficial occlusal flat dentin of these premolars were exposed, finished with wet 600-grit silicon carbide paper. Under four wet and dry conditions (overwet, blot dry, one-second dry and desiccated group), resin composite was bonded using Single Bond(SB)or Prime & Bond NT(PB)according to the manufacturers' instruction. The teeth were longitudinally sectioned in the "x" and "y" directions to obtain bonded sticks with a cross-sectional area of 0.81mm 2 with a slow-speed diamond saw. The specimens were tested in tension at 1mm/min. Results: For both SB and PB, the blot dry groups and one-second dry groups revealed significantly higher bond strengths than the overwet and desiccated groups. Conclusions: It is important for the ethanol/water-based and acetone-based adhesive systems to keep the dentin surface an appropriate moisture condition in clinical situation.