根管治疗后面单面缺损双尖牙修复方式的生物力学研究

A biomechanical study on the restorations of occlusal cavities in endodontically treated bicuspid

目的:从生物力学角度比较不同方法修复根管治疗后双尖牙的效果,并探询最佳方案。方法:实验通过收集对称的双尖牙,对照组为完整离体牙,试验组制备根管治疗及牙合面单面缺损模型,试验一采用银汞充填;试验二采用高强度粘结性材料FX-II充填;试验三为银汞充填后再加冠修复;1mm/min加载于与牙体长轴成45°颊尖舌斜面中点测试破坏载荷,用SPSS10.0软件包进行配对分析。结果:试验一、试验二P<0.05,充填组破坏载荷低于对照组;试验三P<0.05全冠组破坏载荷高于对照组。结论:可认为从生物力学角度来讲,牙合面单面缺损的最佳修复方法是全冠修复。

Objective： To comparc the effects of different restorations for endodonticaUy treated bicuspid from the biomechanical point of view and explore the best method of treatment. Methods： 15 pairs of symmetry maxillary first bicuspids from 15 patients were collected and randomly divided into 3 experimental groups with intact teeth as control group. The model of occlusal defects was established. The defects were restored with amalgam filling, FX- II filling and amalgam filling combined with crowns respectively after endodontic treatment in the 3 experimental groups. The central points of buccal and palatal cuspid were loaded on Instron 4320 universal tests machine at a speed of lmm/min at a 45 degrees angle to the axis until the teeth were broken. The fracture strength was recorded and the data were analyzed statistically by SPSS10.0 software. Results： The fracture strength was lower in group 1 and group 2 than in the control group （P〈0.05）. But the fracture strength was higher in group 3 than in the control group. Conclusion： The most appropriate method of restoring endodontically treated teeth with occlusal defects is full crown from the biomechanical point of view.