Tay F R, Pashley D H
Conservative Dentistry, Faculty of Dentistry, The University of Hong Kong, 34 Hospital Road, Hong Kong SAR, China.
Dent Mater. 2001 Jul;17(4):296-308. doi: 10.1016/s0109-5641(00)00087-7.
This study examined, with the use of transmission electron microscopy (TEM), the aggressiveness of three self-etching adhesive systems in penetrating dentin smear layers of different thickness.
Dentin disks were produced from extracted human third molars. For the control group, the middle dentin surface was cryofractured to create a bonding surface that was devoid of a smear layer. The experimental teeth were polished with wet 600 or 60-grit SiC paper to produce bonding surfaces with thin and thick smear layers. They were bonded using one of the three self-etching systems: Clearfil Mega Bond (Kuraray), Non-Rinse Conditioner and Prime&Bond NT (Dentsply DeTrey) and Prompt L-Pop (ESPE). Bonded specimens were then demineralized and embedded in epoxy resin for TEM examination.
For Mega Bond, thin authentic hybrid layers between 0.4-0.5 microm were found. Smear layer and smear plugs were retained as part of the hybridized complex. For Non-Rinse Conditioner/Prime&Bond NT, the authentic hybrid layers were between 1.2-2.2 microm thick. Smear layer and smear plugs were completely dissolved in dentin with thin smear layers, but were partially retained as part of the hybridized complex in those with thick smear layers. For Prompt L-Pop, authentic hybrid layers were 2.5-5 microm thick and smear layer and smear plugs were completely dissolved even in dentin with thick smear layers.
Contemporary self-etching systems may be classified as mild, moderate and aggressive based on their ability to penetrate dentin smear layers and their depth of demineralization into the subsurface dentin. The more aggressive system completely solubilized the smear layer and smear plugs and formed hybrid layers with a thickness approaching those of phosphoric acid conditioned dentin.
本研究运用透射电子显微镜（TEM），检测三种自酸蚀粘结系统穿透不同厚度牙本质玷污层的侵蚀性。
从拔除的人类第三磨牙制备牙本质片。对照组中，将牙本质中间表面冷冻断裂以形成无玷污层的粘结表面。实验牙用湿600号或60目碳化硅砂纸打磨，以产生薄玷污层和厚玷污层的粘结表面。使用三种自酸蚀系统之一进行粘结：Clearfil Mega Bond（可乐丽）、免冲洗粘结剂和Prime&Bond NT（登士柏德特雷）以及Prompt L-Pop（贺利氏古莎）。然后将粘结标本脱矿并嵌入环氧树脂中进行TEM检查。
对于Mega Bond，发现有厚度在0.4 - 0.5微米之间的薄的真实混合层。玷污层和玷污栓作为杂交复合体的一部分保留下来。对于免冲洗粘结剂/Prime&Bond NT，真实混合层厚度在1.2 - 2.2微米之间。在薄玷污层的牙本质中，玷污层和玷污栓完全溶解，但在厚玷污层的牙本质中，它们部分作为杂交复合体的一部分保留下来。对于Prompt L-Pop，真实混合层厚度为2.5 - 5微米，即使在厚玷污层的牙本质中，玷污层和玷污栓也完全溶解。
当代自酸蚀系统可根据其穿透牙本质玷污层的能力以及向牙本质表层下脱矿的深度分为轻度、中度和侵蚀性。侵蚀性更强的系统能完全溶解玷污层和玷污栓，并形成厚度接近磷酸预处理牙本质的混合层。
