Long-term degradation of resin-dentin interface in vivo

粘接树脂与牙本质之间粘结的长期耐久性对粘结修复体的寿命具有重要意义。目标。这项体内长期研究是为了评估口腔中树脂-牙本质键的降解，以及验证三维粘结界面将随着时间的推移在体内显示形态变化的假设。材料和方法：1只日本猕猴(Macaca Fuscata)的12颗完整牙齿在全身麻醉下制作非常浅的碟状牙本质洞。用Clearfi Liner Bond II和Clearfi Photo后牙树脂复合体修复洞洞。在三个不同的时间拔牙：即刻、180天和360天。处死猴1天后，以1 mm/min的十字头速度对3个时间段的标本进行微拉伸粘结试验。用场发射扫描电子显微镜(FE-SEM)观察了失效键的表面。结果：本研究成功地进行了粘结强度测试，在一年的测试过程中，粘结强度稳定在约19兆帕。扫描电子显微镜对失效表面的观察显示，杂化层顶部和粘结剂树脂内部的孔洞随着时间的推移而增加。意义：可以使用微拉伸粘结试验在体内评估长期粘结，在粘结强度之后可以评估粘接界面的形态变化。

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.