【作者】 张强；

【导师】 汲平；

【作者基本信息】 山东大学 ， 口腔临床医学， 2007， 硕士

【摘要】 目的：通过体外力学实验比较金属和玻璃纤维两种不同材料桩核修复系统对喇叭口状残根修复后牙齿抗折性能的影响，并为临床应用提供依据。方法：选择20颗近期拔除的完整人上颌第一前磨牙，自釉牙骨质界上1mm处截冠，然后残根行完善根管治疗，根管口磨除部分牙体组织后形成喇叭口状，其中喇叭口部位轴壁厚度0.5mm，高度2mm，模拟临床上的喇叭口状残根的形状。然后试件被随机分成两组，分别进行镍铬合金桩、玻璃纤维桩两种不同桩核材料的桩核冠修复。所有样本用环氧树脂在牙根颊面釉牙骨质界下2mm处包埋，包埋块置于电子万能测试机上进行牙根抗折性能的测试。加载点为颊尖舌斜面三角嵴中点，方向与牙体长轴成45°角，下降速度为1mm／min。记录破坏载荷并观察牙根折裂形式，牙根破坏载荷输入SPSS12.0软件包进行统计学的处理。结果：牙根抗折力镍铬合金桩核组为0.511±0.087KN；玻璃纤维桩核组为0.787±0.185KN。经统计学单因素方差分析，结果显示：牙根抗折力镍铬合金桩核组小于玻璃纤维桩核组(P＜0.01)。可修复性断裂模式见于玻璃纤维桩组，即：纤维桩从颈部折断而牙根是完整的；不可修复性破坏模式见于对照组，即：牙根折裂而金属桩是完整的。结论：在喇叭口状残根保存修复中，玻璃纤维桩核系统有提高喇叭口状残根修复后牙根抗折性能的作用，玻璃纤维桩核系统应该为一种较好的修复选择方式。更多还原

【Abstract】 Objective: To compare the fracture resistance of endodontically treated tooth with flared root canal restored with two different post systems of metal and glass-fiber trough mechanical test for clinical application.Methods: Twenty recently extracted human maxillary first premolars were endodontically treated after the crowns were cut off from the point 1mm up the cemento-enamel junction. The hard tooth tissue was cut off from the root canal orifice to form the shape of flared root canal with axial wall 0.5mm thick and 2mm high. And then all the samples were randomly divided into two groups. Each group teeth were restored with Ni-Cr alloy and glass-fiber post-core systems differently. All the specimens were embodied in epoxy resin mass vertically from the point 2mm below the cemento-enamel junction. All the specimens were placed in the universal material testing machine for fracture resistance test in speed of 1mm/min to broken up while the load angle was 45 degree to the long axis of the teeth, as the load is pointed to the middle of the lingual surface on the buccal cusp. Recorded the top loads and mode of root fracture while the top loads were analyzed through SPSS12.0 software.Results: The fracture resistance strength of flared root canal teeth restored with Ni-Cr alloy systems group was0.511±0.087KN while glass-fiber post-core systems group was0.787±0.185KN. The fracture resistance strength of flared root canal teeth restored with Ni-Cr alloy systems group was lower than glass-fiber post-core systems group through one-way ANOVA (P<0.01) .Repairable fracture with glass-fiber post fractured and root intact was observed in glass fiber post group while un-repairable fracture with root fractured and metal post intact were observed in control group.Conclusion: Glass-fiber post-core systems could improve the fracture resistance strength of flared root canal teeth and it was an appropriate selection in flared root canal tooth restoration.更多还原