复合树脂修复是目前口腔临床最常用的直接修复方式。因结合界面脱粘接而引起的继发龋是引起其失败的第一危险因素，而脱粘接是树脂聚合动态过程中收缩应力的最终值或形成速率战胜粘接力的竞争结果。为预测及预防修复体界面脱粘接的发生，需对二者间的竞争机制有全面深刻的了解。收缩应变及应力的形成是一个快速的动态发展过程，而目前对固化过程中粘接力形成的动力学特性尚未见研究。本课题旨在通过实验获得收缩应变、弹性模量等参数随固化时间的变化关系，并基于此数据，在具有临床代表性的三维有限元模型中预测收缩应力的动力学表现；同时通过拉伸试验，获得不同因素下粘接力的动力学表现，建立预测模型，最终综合比较收缩应力与粘接力的发生与发展过程，判断界面竞争结果，进而对脱粘接进行有效预测。研究结果将揭示光固化树脂脱粘接的动力学机制，有助于指导临床优化操作，预防及减少脱粘接的发生，延长修复体寿命，同时引导新一代树脂及光固化装置的开发。

Resin composite restorations are currently the most common treatment options in clinical direct restoration. However, secondary caries caused by interfacial debonding is the main reason for their failure. During polymerization, there exists a competition at the tooth-restoration interface between shrinkage stress and bond strength. Debonding is the result of shrinkage stress having a higher final value or higher rate of formation over bond strength. Therefore, to predict or prevent the occurrence of interfacial debonding, a comprehensive and in-depth understanding of the competition between shrinkage stress and bond strength is necessary. To date, research has found that the development of shrinkage strain and shrinkage stress is a rapid dynamic process. But the dynamic characteristics of bond formation during curing has seen very little research. This project aims to obtain through experiments the correlations between the temporal changes of properties such as shrinkage strain and Young's modulus of resin composites during curing. Based on these data, prediction is then made using clinically representative 3D finite element models for the dynamic behavior of shrinkage stress. At the same time, tensile tests will be carried out under different conditions to obtain the dynamic formation of bond strength, from which predictive models will be constructed. Finally, by comparing the occurrences and developments of shrinkage stress and bond strength, we can conduct effective prediction for debonding based on the results of the competition at the interface. The results will help optimize the selection of materials, treatment options and restorative techniques so as to maximize the lifetimes of resin composite restorations. It will also provide a more fundamental understanding on the kinetics of light curing, which will guide the design of the next-generation composites and curing lights.