螺纹牙本质钉的固位力测试

Bio-mechanical test of tension resistibility of thread pins and discussion of retention principles

目的:测试螺纹牙本质钉的抗拉能力,并探讨其固位原理。方法:在新鲜无龋的12颗离体牙上制备钉道50个,旋入固位钉,用拉伸试验机测试其抗拉能力,并记录固位钉脱位过程中拉力的变化。结果:在新鲜、无龋的12颗第三磨牙的牙本质上制备共50个钉道,成功旋入固位钉48枚。通过试验,48枚固位钉抗拉力最大值为426.37牛顿,最小值为142.22牛顿,均值为208.56±2.27牛顿。固位钉被拉出后,在其螺纹内及钉道口周围可见白色粉末状物。结论:牙本质钉的抗拉能力为208.56±2.27牛顿,95%可信区间最大不超过210.83牛顿,最小不低于206.29牛顿。

Objective:To measure the tension resistibility of dental pin, and to discuss the retention principle of the dental pin. Methods:50 pin holes were drilled in fresh and non-carious third molars, and each pin hole was screwed in with a thread pin. The retention resistibility was measured and the changes of tension in the course of pin dislocation were recorded by a tensile testing machine. Results:Among the 50 pins used, 48 were successfully screwed into the hole. By the test, the maximum value was 426.37N, the minimum 142.22N, with an average of 208.56±2.27N. White dentin powder could be seen around the pin hole and on the pin with the pin pulled out of the hole. Conclusion: The tension resistibility of dental pin is 208.56±2.27N, the maximum value is not exceed 210.83N, the minimum is not lower than 206.29N.