中文摘要：

目的：探讨循环加载对牙本质黏结界面纳米渗漏的影响。方法：选用3种黏结系统：Prime ＆ Bond NT（NT），Adper Prompt（AP）和Contax。用扫描电镜（SEM）观察这3种黏结系统在有无循环加载的作用下，牙本质黏结断面银渗漏情况，并用NIH图像分析软件量化处理，以界面银沉积面积占断裂界面的百分比来评价纳米渗漏程度。结果：各对照组银沉积面积的百分比分别为NT（11．48％±2．84％）、AP（21．18％±3．66％）、Contax（14．30％±2．52％），实验组分别为NT（25．20％±4．69％）、AP（38．96％±8．78％）、Contax（29．94％±4．51％）。结论：无论加载与否，所用3种黏结系统都不能避免纳米渗漏的产生；循环加载使黏结系统黏结界面纳米渗漏增加，尤其以AP最为显著。

英文摘要：

AIM：To evaluate the effects of cyclic mechanical loading on the nanoleakage within resin - dentin interfaces. METHODS：Prime Bond NT（ NT）, Adper Prompt （AP） and Contax were chosen for the test. The specimens of the three bonding systems with or without cyclic mechanical loading were studied with scanning transmission e- lectron microscopy（ SEM ） to identify the amount and distribution of silver uptake. They were then subjected to image analysis by NIH Image PC. Leakage scores of each restoration were calculated as the percentage of the total area of the broken interface that was penetrated by silver nitrate. RESULTS：The ratios of the leakage of the control group were NT（ 11.48% ± 2.84% ）, AP（21.18% ± 3.66% ） and Contax （ 14.30% ± 2.52% ） respectively. Those of the experimental group were NT（25.20% ±4.69% ）, AP（38.96% ± 8.78% ） and Contax（29.94% ±4.51% ） respectively. CONCLUSION：All the bonding systems in this study can not resist nanoleakage; cyclic mechanical loading can increase the nanoleakage within resin - dentin interfaces of the three bonding agents, especially for the AP group.