Collard E W, Caputo A A, Standlee J P, Duncanson M G
J Prosthet Dent. 1981 Feb;45(2):156-9. doi: 10.1016/0022-3913(81)90333-4.
Combining stress, analysis, microscopic examination, mechanical testing of the shear mechanism, and retention of the Reten Pin leads to the following conclusions: 1. The suggested 0.006 inch pin-channel mismatch induces high lateral and apical stresses. Microscopically, this was seen to correlate with injury to the dentin. 2. The degree of retention was increased by using a smaller pin-channel mismatch. This correlates with smaller stresses and reduced dentinal damage. 3. The shear mechanism acts in a uniform manner, with a relatively small variation from the mean. It is suggested that for the best results the manufacturer should supply larger twist drills and pins with a somewhat deeper self-shearing groove to minimize apical involvement during shearing of the handle from the pin.
结合应力分析、微观检查、剪切机制的力学测试以及固位钉的固位情况，得出以下结论：1. 建议的0.006英寸钉道不匹配会产生较高的侧向和根尖应力。在显微镜下，这与牙本质损伤相关。2. 使用较小的钉道不匹配可增加固位程度。这与较小的应力和减少的牙本质损伤相关。3. 剪切机制以均匀的方式起作用，与平均值的差异相对较小。建议为获得最佳效果，制造商应提供更大的麻花钻和带有稍深自剪切槽的固位钉，以尽量减少在将手柄从固位钉上剪切下来时根尖的累及。
