不同颈缘弯曲度和肩台形态的泽康全瓷冠的精度

Marginal fit of Cercon all-ceramic CAD/CAM crowns with different finish line curvature and margin

目的调查不同颈缘弯曲度和肩台形态的泽康CAD/CAM全瓷冠的边缘精度。方法准备6种不同形态的基牙(弯曲度:1mm,3mm,5mm;肩台外形:圆弧肩台,直角肩台)。制作30个泽康CAD/CAM全瓷冠(每种肩台各5个),测定陶瓷基底冠和全瓷冠的边缘缝隙。采用双因子ANOVA分析后用T检验测定有无统计学差异。结果弯曲度1mm,3mm,5mm圆弧肩台的泽康全瓷冠的边缘缝隙分别为51(21)μm,53(22)μm,54(20)μm。弯曲度1mm,3mm,5mm直角肩台的泽康全瓷冠的边缘缝隙分别为49(18)μm,51(19)μm,50(22)μm。统计结果显示6种基牙之间没有显著性差异。结论泽康全瓷冠有良好的边缘精度,颈缘弯曲度和肩台形态对泽康全瓷冠的边缘精度没有显著影响。

Objective To evaluate the marginal fit of Cercon all - ceramic CAD/CAM crowns with different finish line curvature and margin in vitro. Methods Six groups of abutments （finish line curvature： linm, 3mm and 5mm, margin shape： chamfer and shoulder） were prepared. Thirty all -ceramic crowns were fabricated （five for each group）. The marginal gaps of copings and veneered crowns were measured respectively. The data were calculated and analyzed with two - way ANOVA and Tukey HSD test （α = 0.05 ）. Results The mean marginal gaps and their standard difference （SD） of veneered crowns for lmm, 3mm and 5mm - curvature- chamfer were 51 and 21μm, 53 and 22μm, 54 and 20μm respectively. The mean marginal gaps and their SD of veneered crowns for lmm, 3mm and 5mm - curvature - shoulder were 49 and 18μm, 51 and 19μm, and 50 and 22μm respectively. There was no significant difference on the marginal gaps among six groups of abutments. Conclusion The marginal gaps of Cercon all - ceramic crowns were within the range of clinically acceptable values. The abutment finish line curvature and shape had no significant influence on the marginal fit of Cereon all - ceramic crowns.