【摘要】 目的:比较不同颈环高度对CAD/CAM氧化锆全瓷冠抗压碎力的影响。方法:设计制作具有不同颈环高度(mm)的氧化锆基底冠,分别为0(A组)、1.0(B组)、1.5(C组)、2.0(D组)、2.5(E组),每组10颗。常规堆筑、烧结饰面瓷后,将样本粘接固定在金属代型上进行抗压碎力测试,记录样本发生破坏时的瞬间力值和折裂形式。结果:各组抗压碎力(kN)测试结果分别为:A组0.95±0.39、B组1.29±0.50、C组1.54±0.28、D组2.04±0.19、E组2.27±0.53,5组整体比较,P<0.05。全瓷冠的破坏形式表现为单纯饰面瓷剥脱、饰面瓷剥脱合并基底冠破损2种类型。结论:当颈环高度≥1.5 mm时,能够显著提高氧化锆全瓷冠的抗压能力。更多还原

【Abstract】 Objective: To evaluate the influence of cervical collar height on the compressive strength of CAD/CAM zirconia-ceramic restoration. Methods: Zirconia cores were manufactured and divided into 5 groups( n = 10) based on the cervical collar height( mm) : 0. 0( A),1. 0( B),1. 5( C),2. 0( D) and 2. 5( E). After veneered with porcelain,all the samples were cemented on the metal tooth analog and then mounted in an universal test machine. The force was applied at a crosshead speed of 1mm / min until catastrophic failure occurred. Fracture loads and failure modes were recorded. Results: Mean of the fracture strength values( kN) in group A,B,C, D and E were 0. 95 ± 0. 39,1. 29 ± 0. 50,1. 54 ± 0. 28,2. 04 ± 0. 19 and 2. 27 ± 0. 53 respectively( among groups,P < 0. 05). Two types of fracture modes were observed: chipping of the veneering porcelain and fracture of the veneering porcelain together with the framework. Conclusion: Zirconia coping design with 1. 5 mm cervical collar height may increase the compressive strength of CAD / CAM zirconia-ceramic restoration.更多还原