不同水门汀粘固桩核对牙本质应力的影响

Effects of different post luting cements on dentinal stress

目的:探讨不同水门汀粘固桩核对牙本质应力的影响以及其在防止牙根折裂方面的作用。方法:采用磷酸锌水门汀(ZOP)、树脂水门汀(RC)、玻璃离子水门汀(GIC)及树脂改良型玻璃离子水门汀(RMGIC)4种临床常用水门汀粘固根管桩后,在加载荷1(部位是牙冠舌侧切、中1/3交界处,方向与牙长轴成30°角,加载力的大小为100 N)和载荷2(部位是牙冠切端,方向与牙长轴平行,加载力的大小为100 N)情况下,应用三维有限元法(3D-FEM法)分析牙本质应力峰值及应力分布的变化。结果:加载荷1时,RMGIC、GIC、RC及ZOP均能降低牙本质的应力峰值,降低率依次为45.02%、45.50%、45.98%和46.30%,其中ZOP对牙本质应力峰值降低率最大;加载荷1及载荷2时,4种水门汀对牙本质应力分布的影响均无明显区别。结论:4种临床常用水门汀对牙本质的应力峰值均有所降低,其中ZOP的作用优于其他3种水门汀。

Aim ： To analyze the effects of different luting cements on the peak of the dentinal stress and dentinal stress distribution in order to evaluate their roles in fracture resistance of endodontically treated teeth. Methods ：3D finite element method was used to analyze the effects of four different luting cements,including ZOP, RC,GIC, and RMGIC,whieh have different modulus of elasticity on the stress distribution of the dentin and the peak of dentinal stress. Results： All these ce- ments could reduce the peak of the dentinal stress, and the descendent rate of ZOP, RC, GIC and RMGIC was 46.30% , 45.98% ,45.50% and 45.02%. All the cements bad no significant difference in tbe dentinal stress distribution. Conclusion ： Within the limitations of this study, ZOP shows better condition than the other cements in reducing the peak of dentinal stress.