3种酸蚀方法处理硬化牙本质表面的超微形态研究

Ultrastructural study of sclerotic dentin in non-carious cervical lesion treated by three different etching modes

目的采用3种不同的酸蚀方法处理牙颈部非龋性缺损中的硬化牙本质,比较其表面超微形态的变化。方法选择15颗因牙周病拔除具有典型牙颈部非龋性缺损的天然前磨牙作为实验组,同时选用15颗拔除的冠根完好的前磨牙,人工机械预备牙颈部楔状缺损作为对照组。实验组和对照组各随机分成3组,分别采用15%磷酸处理30s、35%磷酸处理15s、自酸蚀处理剂AdperPromptL-Pop处理15s。扫描电镜观察表面形态的变化。结果硬化牙本质的大部分牙本质小管内可见柱状的矿化结晶体。3种酸蚀处理均不能去除牙本质小管内的硬化结晶体。结论硬化牙本质的表面结构与正常牙本质存在差异,其牙本质小管内堵塞的矿化结晶体可能对黏接产生影响。自酸蚀处理剂AdperPromptL-Pop的酸蚀脱矿能力低于15%和35%的磷酸。

Objective To examine the ultrastructure of the surface of sclerotic dentin in non-carious cervical lesions treated by three different etching modes. Methods Naturally-occurring, non-carious cervical lesions on extracted premolars were treated separately using 15% phosphoric acid for 15 seconds,35% phosphoric acid for 15 seconds or a self-etching primer Adper Prompt L-Pop for 15 seconds. Artificially prepared wedge-shaped lesions were also made in sound premolars and treated by the same three etchants as control. The morphological change of the dentin surface conditioned with the etchants were studied by SEM. Results Most of the dentin tubules of sclerotic dentin were occluded by rod-like crystal casts, and all of the three etching modes in this study were unable to effectively dissolve the sclerotic casts. Conclusion The surface structure of sclerotic is quite different from that of normal dentin. Bonding to sclerotic dentin may be compromised by the occluded dentin tubules. The etching ability of the self-etching primer Adper Prompt L-Pop is weaker than those of 15% and 35% phosphoric acid.