前牙断根再接的实验研究

Experimental study of reattachment of incisal root fracture

目的:建立离体牙断根再接模型,检测黏结剂Super-BondC&B断根再接牙抗折力,以及根管内置铸造合金桩辅助固位设计对抗折力的影响,为断根再接的临床应用提供参考。方法:使用4466型通用测试机检测Super-BondC&B黏结的断根再接牙(实验一组)、Super-BondC&B黏结联合根管内置铸造合金桩的断根再接牙(实验二组)以及完整牙(对照组)的抗折力。结果:抗折力分别为:对照组1050.3±128.8N、实验一组554.5±81.2N、实验二组732.1±62.4N。经统计学处理,三组间抗折力差异显著(P<0.01)。结论:本实验结果显示Super-BondC&B断根再接牙的抗折力可以达到完整牙抗折力的53%;联合根管内铸造合金桩断根再接牙达到完整牙抗折力的70%,合适的辅助固位设计可以增强再接牙抗折力。

AIM:To evaluate the shear bond strength of the fractured root of incisors reattached by Super-Bond C&B bonding agent or plus an assistant preparation. METHODS:A model of reattachment of the fracture root incisors in vitro was established.30 bovine incisors were divided into three groups randomly-a control group and two experimental groups,10 in each.The specimens of two experimental groups were sectioned at middle of the root.The fragments in experimental group one were reattached by Super-Bond C&B bonding agent.In experimental group two the Super-Bond C&B bonding agent was used with root canal castable Ni-Cr metal post.The shear bond strength of the specimens of experimental and control groups were measured by a 4466 Universal Testing Instron Machine.RESULTS:The average shear bond strength of the specimens in the control group was 1050.3±128.8 N,554.5±81.2 N in experimental group one and 732.1±62.4 N in experimental group two.CONCLUSION:The shear bond strength of the specimens.of experimental group one and experimental group two restored the strength of the control teeth about 53% and 70% respectively.The latter displayed significantly more strength than those of the former.