垂直加载时基底材料及充填体对牙齿抗折力的影响

Effect of various cavity design, lining and restorative materials on the fracture resistance of teeth

目的 研究窝洞形态、基底材料和充填体如何共同影响牙齿的抗折力。方法 采用三因素不同水平的析因实验设计 ,用上颌离体第一前磨牙在万能测试机上垂直加载直至折裂。记录最大折裂力和折裂方式 ,用三因素方差分析分析结果。结果 窝洞的形态和充填体种类对牙齿的抗折裂力影响明显 ,不同材料牙折的方式不同。结论 充填体的种类和窝洞形态是影响抗折力的主要因素 ,洞型和充填体之间存在交互作用。

Objective To evaluate the influence of various cavity designs, lining and restorative materials on fracture resistance of teeth in vitro Methods Factorial design with three factors and various levels was used 36 extracted human maxillary premalors were prepared for occlusal cavity, MO cavity and MOD cavity Various base material and restorations were used All teeth were thermocycled and mounted for testing and then were loaded until fracture The results were analyzed by a three way ANOVA Fracture patterns were observed at the same time Results There was significant difference in fracture resistance among various cavity designs and restorations The fracture patterns were different Conclusions The different classes of cavities and various restorations have significantly influence upon fracture resistance of teeth There are interactions between cavities and restorations