不同牙体预备方法对模拟重度楔状缺损牙体桩核冠修复后抗折特性的影响  

Effects of different tooth preparations on the fracture behavior of teeth with severe wedge-shaped defect restored with post and core crowns

作　　者：冯丹丹[1] 祁冬[1] 林雪芬[1] 丁婷婷[1] 汲平[1,2] 

机构地区：[1]山东大学口腔医院修复科 [2]山东省口腔生物医学重点实验室,济南250012

出　　处：《华西口腔医学杂志》2014年第2期157-161,共5页West China Journal of Stomatology

摘　　要：目的探讨不同牙体预备方法对重度楔状缺损牙体桩核冠修复后抗折特性的影响,为临床修复治疗提供理论依据。方法将64颗离体下颌第一前磨牙按不同的牙体预备和修复方法分组,按照颊侧楔状缺损方悬突牙体去除与否(不去为A,去除为B)和颊侧楔状缺损下方是否制备牙本质肩领(未制备为C,制备为D),以及铸造桩核修复(设为E)或纤维桩核修复(设为F)随机分为A1-1(A+C+E)、A1-2(A+C+F)、A2-1(A+D+E)、A2-2(A+D+F)、B1-1(B+C+E)、B1-2(B+C+F)、B2-1(B+D+E)、B2-2(B+D+F)共8组,每组8颗,建立重度楔状缺损牙模型,各组按分组内容进行桩核冠修复,用电子万能试验机进行加载,测试各组的抗折载荷,观察折裂模式。结果 1)抗折载荷的比较:A1-1组>B1-1组,A1-2组>B1-2组,B2-1组>B1-1组,B2-1组>B2-2组,其差异均有统计学意义(P<0.05)。2)A1-2、B1-2组可修复性折裂比例均为37.5%,其余各组均为0,A1-2组和B1-2组明显高于其他组。结论重度楔状缺损患牙桩核冠修复时保留颊侧悬突牙体对承受抗折载荷有利,修复时不建议颊侧设计牙本质肩领;纤维桩较铸造桩更有利于牙体折裂后的再修复。Objective This study aimed to investigate the effects of different tooth preparations on the fracture strength and pattern of failure of teeth with severe wedge-shaped defect restored with post and core crowns. Methods According to whether the teeth above the wedge-shaped defect was removed （represented by B） or not （represented by A）, the ferrule next to the wedge-shaped defect was prepared （represented by D） or not （represented by C）, the cast post-and-core was chosen （represented by E） or glass-fiber post and resin core was chosen （represented by F）. A total of 64 human mandibular premolar teeth were randomly divided into 8 groups： A1-1 （A＋C＋E）, A1-2 （A＋C＋F）, A2-1 （A＋D＋E）, A2-2 （A＋D＋F）, B1-1 （B＋C＋E）, B 1-2 （B＋C＋F）, B2-1 （B＋D＋E）, B2-2 （B＋D＋F）, each group 8 teeth. All the teeth were prepared and restored accordingly and then mounted on an electronic pressure universal testing machine. The maximum fracture strength and the patterns of failure were recorded. Results 1） The fracture strength of GroupA1-1 〉that of Group B 1-1, Group A1-2〉Group B 1-2, Group B2- 1 〉Group B 1-1, and Group B2-1 〉Group B2-2 with significant differences （P〈0.05）. 2） The patterns of repairable fracture in Group A1-2 and B1-2 were both 37.5%, and that of the other groups were 0. Furthermore, the difference was significant, and Group A1-2 and B 1-2 were higher than other groups. Conclusion The maintenance of the overhang above the severe wedge-shaped defect aid in the improvement of the fracture strength of the tooth restored with post and core crown. The ferrule of the wedge-shaped defect is not recommended to be prepared. Furthermore, the glass-fiber post and resin core is favorable for the re-repair of the teeth than the cast post and core.

关 键 词：楔状缺损 悬突牙体 牙本质肩领 桩核 抗折性 

分 类 号：R783.3[医药卫生—口腔医学]