上前牙薄弱根管重塑材料与根管内壁黏结界面的显微分析研究

目的:探索Bis-Core复合树脂、水调玻璃离子重塑根管后与根管内壁的黏结界面的显微结构。方法:选择新鲜拔除的人上前牙,根管治疗后去冠,将牙根从中一剖为二,分别用复合树脂、水调玻璃离子对根管壁进行黏结。硬组织切片机制备样本,光学显微镜和原子力显微镜观察根管重塑后材料与牙体界面的微细结构特征。结果:树脂与牙本质的黏结界面上有5μm厚度的玷污层,牙本质小管内的树脂长度约为20μm,而玻璃离子与牙齿界面结合紧密,但无渗透现象。结论:在与根管内壁的黏结方面,Bis-Core树脂优于水调玻璃离子,树脂渗透是其与牙体牢固黏结成整体的重要因素。

Micromorphology analysis of bonding interface between material and dentin after root canal rehabilitation

Objective:To observe the microstructure of interface between material and dentin after root canal rehabilitation. Methods:Three human maxillary incisors extracted within one week were used. After crowns being removed and received root canal treatment, they were used for the study. The root was split into two parts along the long axis, then the bonding interface was made with high speed diamond bur. Bis-Core and Chemil Superior glass-ionomer were stacked on root canal inner wall respectively and the teeth were split along with the long axis with Isomet saw, in order to expose bonding interface. The microstructure of bonding interface of the samples were analyzed by optical microscope and atomic force microscope(AFM). Results: AFM observation of the adhesive interface specimens showed that Chemil Superior glass-ionomer and teeth knitted together completely and no filling invaded into dentin tube. While the bonding interface between Bis-Core and dentin, dentin primer infiltrated into dentin tube and matrix around through the smear layer and colophony protruded. Conclusion:The observations reveal the extent of resin penetration into the dentinal tubules provides a very strong bonding. This is a fundamental cause of resin better bond to tooth.