后牙氧化锆单端固定桥抗折强度的研究  

Fracture resistance of zirconia cantilever fixed bridge in the posterior dentition

作　　者：夏菁[1,2] 马小青[1,2] 张昕[1,2] 陈莹莹[1,2] 张怀勤[1,2] 

机构地区：[1]南京医科大学口腔疾病研究江苏省重点实验室,江苏南京210029 [2]南京医科大学附属口腔医院修复科,江苏南京210029

出　　处：《口腔生物医学》2016年第2期83-86,共4页Oral Biomedicine

基　　金：江苏高校优势学科建设工程资助项目(2014-37)

摘　　要：目的：探讨冷热循环对氧化锆晶相结构的影响,并测试两种不同厚度后牙氧化锆单端固定桥基底支架的抗折强度。方法：制作10 mm×15 mm×1 mm氧化锆试件2个,分为冷热循环组（10 000次,5~55℃）和对照组,用X射线衍射仪（XRD）测定试件单斜相含量。运用CAD/CAM系统制作后牙氧化锆单端固定桥基底支架12个,按照基底冠厚度分为0.7 mm和0.8mm两组,每组6个。将所有支架粘固于钴铬合金模型上,在万能力学试验机上进行抗折强度测试,记录试件断裂时的临界载荷并进行单因素方差分析。结果：冷热循环前后的氧化锆试件均未出现单斜相;后牙氧化锆单端固定桥基底支架断裂的临界载荷分别为（1 262.08±100.57）N（0.7 mm组）和（1 345.87±191.17）N（0.8 mm组）,经统计学分析无显著性差异（P〉0.05）。结论：冷热循环对氧化锆晶相结构无影响,两组后牙氧化锆单端固定桥基底支架的抗折强度均大于口腔最大咬合力888 N。Objective：To investigate the effect of thermocycling on the crystal structure of zirconia and measure the fracture resist-ance of zirconia cantilever fixed bridge with 0.7 mm and 0.8 mm in the posterior dentition. Methods： Two 10 mm ＆#215; 15 mm ×1 mm zirconia specimens （ one served as control and the other subjected to thermocycling, 10 000 times, at 5~55℃） were prepared. X-ray diffraction （ XRD） was used to estimate the relative amount of monoclinic phase in each specimen. 12 zirconia cantilever fixed bridge frameworks were prepared by using CAD/CAM systems and divided into two groups （0.7 mm and 0.8 mm, 6 in each group）. All frameworks were cemented on the model using glass ionomer luting cement and then subjected to compression test by using a Universal Testing Machine. The loads at fracture were recorded and one-way ANOVA was used to analyze the data. Results：No specimen exhibi-ted monoclinic phase before and after thermocycling.There was no significant difference in the fracture resistance between group 0.7 mm （1 262.08±100.57） N and group 0.8 mm （1 345.87±191.17） N （P〈0.05）. Conclusions：Thermocycling has no effect on the crystal structure of zirconia. The loads at fracture in both groups were more than the maximum human bite force （ 888 N） .

关 键 词：氧化锆 单端固定桥 冷热循环 抗折强度 

分 类 号：R783.1[医药卫生—口腔医学]