Long-term degradation of resin-dentin interface in vivo

粘接树脂与牙本质黏结的长期耐久性对粘接修复体的寿命至关重要。目标。本研究旨在评估树脂-牙本质键在口腔内的降解情况，并验证三维黏合界面在体内随时间发生形态变化的假设。材料与方法：在全身麻醉下，对1只日本猕猴（Macaca fuscata） 12颗完整牙齿制备极浅的碟状牙本质空腔。使用Clearfil Liner Bond II和Clearfil Photo Posterior树脂复合材料修复牙槽。在三个不同的时间拔出牙齿；修复体放置后即刻、180天和360天。献祭后1天，三个时间段的标本以1 mm/min的十字头速度进行微拉伸粘结试验。用场发射扫描电镜（FE-SEM）观察了失效键的表面。结果：本研究成功进行了粘结强度测量，在为期一年的测试中，粘结强度稳定在19 MPa左右。对失效表面的扫描电镜观察显示，随着时间的推移，杂化层顶部和粘接树脂内部的孔隙率增加。意义：通过微拉伸键合试验可以在体内评估长期键合，并在键合强度后评估粘附间相的形态变化。

The long-term durability of bonds between adhesive resins and dentin is of significant importance for the longevity of bonded restorations. Objectives. This in vivo long-term study was carried out to evaluate the degradation of resin-dentin bonds in the oral cavity, as well as to test the hypothesis that the three-dimensional ashesive interfac would show morphological changes in vivo over time. Materials and Methods : Very shallow saucer-shaped dentin cavities were prepared in 12 intact teeth of one Japanese monkey (Macaca fuscata) under general anesthesia. The cavities were restored with Clearfil Liner Bond II and Clearfil Photo Posterior resin composite. The teeth were extracted at three different times ; immediate, 180, and 360 days after placement of the restorations. One day after sacrifice of the monkey, specimens of the three time periods were subjected to the micro-tensile bond test at a cross head speed of 1 mm/min. The surfaces of the failed bonds were observed under a field emission scamming electron microscope (FE-SEM). Results : Bond strength measurements in this study were successfully performed and were stable approximately 19 MPa during the one-year testing. Scanning electron microscopic observations of the failed surfaces revealed porosities at the top of the hybrid layr and within the adhesive resin which increased over time. Significance : Long-term bonds can be assessed in vivo using the microtensile bond test, and morphological changes of the adhesive interphase can be evaluated after the bond strength.