计算机辅助设计与制作的一体化氧化锆全瓷桩核抗折力的体外对比实验  

Fracture resistance of teeth restored with one-piece computer aided design and manufacture zirconia posts and cores: an in vitro study

作　　者：周团锋[1,2] 张相皞[3] 王新知[1] 

机构地区：[1]北京大学口腔医学院.口腔医院修复科,北京100081 [2]北京大学口腔医学院.口腔医院第一门诊部,北京100034 [3]北京大学口腔医学院.口腔医院第二门诊部,北京100101

出　　处：《北京大学学报（医学版）》2014年第1期81-85,共5页Journal of Peking University:Health Sciences

摘　　要：目的:比较预成氧化锆全瓷桩、计算机辅助设计与制作的(computer aided design and computer aided manufacture,CAD/CAM)一体化氧化锆全瓷桩核和天然离体牙的抗折力大小,为临床桩核冠修复材料和方式的选择提供一定的参考。方法:采用36颗离体完整的上颌中切牙,随机分为预成氧化锆全瓷桩铸瓷核金属全冠修复、CAD/CAM一体化氧化锆全瓷桩核金属全冠修复和完整离体牙3组,每组12颗。在力学万能实验机上,在冠切缘下2.0mm,沿牙体长轴135°,以1 mm/min的速度加载,测量3组抗折力的大小。结果:完整离体牙组的抗折力最大[(736.33±82.91)N],CAD/CAM一体化氧化锆全瓷桩核组次之[(423.83±54.58)N],预成氧化锆全瓷桩铸瓷核组最小[(311.75±70.12)N],单因素方差分析差异有统计学意义(P<0.001)。结论:CAD/CAM一体化氧化锆全瓷桩核有较高的抗折能力,在前牙美学修复中的应用有一定优势。Objective：To compare the fracture resistance of endodontically-treated teeth restored with prefabricated zirconia posts or one-piece computer aided design and computer aided manufacture （CAD/ CAM） zirconia posts and cores, and unrestored endodontically-treated teeth. Methods： Recently extrac- ted human maxillary central incisors （ n = 36） were endodontically treated and divided into three groups （n = 12 each） ： group 1 was restored with prefabricated zirconia posts （Comospost） and hot pressed ce- ramic cores; group 2 restored with one-piece CAD/CAM zirconia posts and cores; group 3 not restored. The teeth were fixed in a universal load-testing machine; a compressive load was applied at 135 degrees to the long axis of each tooth at a crosshead speed of 1 mm/min until fracture. One-way analysis of variance （Student-Newman-Keuls） was used to determine the significance of the differences in failure load between the groups. Results： The mean fracture loads were （311.75 _＋ 70.12） N, （423.83 ~ 54.58） N and （736.33 ~ 82.91 ） N, respectively. The unrestored teeth exhibited significantly higher fracture resistance than the two groups of restored teeth. The teeth restored with one-piece CAD/CAM zir- conia posts and cores had higher fracture resistance than the teeth restored with prefabricated zirconia posts and hot pressed ceramic cores （P 〈 0. 001 ）. Conclusion： Within the limitations of this study, the root canal-treated teeth restored with one-piece CAD/CAM zirconia posts and cores had a significantly higher failure resistance than the teeth restored with prefabricated zirconia posts. One-piece CAD/CAM zirconia posts and cores can offer some advantages for esthetic prosthodontics.

关 键 词：计算机辅助设计 氧化锆 牙应力分析 桩核技术 体外研究 

分 类 号：R783.3[医药卫生—口腔医学]