残冠轴壁剩余量对两种桩核冠修复体抗折性能的影响

目的:评价牙体不同剩余量对镍铬金属和石英纤维两种桩核冠修复体抗折性能的影响。方法:选用6个月内因正畸治疗需要拔除的完整的下颌单根前磨牙60颗,随机分为6组,按照牙体不同轴壁剩余量制造实验模型。分别使用镍铬金属桩核+镍铬全冠修复或石英纤维桩核+镍铬全冠修复,测试最大载荷力值及折裂模式,所有数据使用SPSS软件进行分析。结果:石英纤维桩核冠修复体的抗折载荷与镍铬金属桩核冠修复体间存在显著性差异(P<0.05);石英纤维桩核修复的不同牙体剩余量各组间抗折载荷存在显著性差异(P<0.05);石英纤维桩核冠修复体可修复性折裂发生率大于镍铬金属桩核冠修复体(P<0.05)。结论:石英纤维桩核较镍铬金属桩核能更好地保护剩余牙体组织。使用石英纤维桩核时,牙体剩余量越多,修复体抗折性能越强。

Effects of different amount of axis walls of residual tooth on fracture resistance ability in two post-core systems

Objective To study the effects of different amount of residual tooth on fracture resistance ability in Ni-Cr alloy post-core system and quarts fiber post-core system. Methods The experiments were performed with a homogeneous sample of sixty intact single-rooted humar mandibular premolars of similar dimensions, extracted in the recent six months from adolescents who were receiving orthodontic treatment. Teeth were randomly divided into six groups with ten each.A teeth were restored with Ni-Cr cast post-core or quarts fiber post-core plus Ni-Cr crown.Fracture resistance was measured with a universal load-testing machine. The reading data of the testing machine and the fracture pattern were recorded and analyzed by SPSS. Results The difference between quarts fiber post-core prosthesis and Ni-Cr alloy post-core prosthesis was significant Differences among groups were restored with quarts fiber post-core which had different axis walls were significant. The possibility of secondary restoration in quarts fiber post-core prosthesis was significantly higher than that in Ni-Cr alloy post-core prosthesis. Conclusion 1.The quarts fibe post-core can protect the residual tooth better.2.1t indicated that the fracture resistance is bette when there is more dentin using quarts fiber post-core.