CAD/CAM氧化锆底层冠适合性的实验研究

Evalution of the adaptation of Cercon CAD/CAM copings

目的:用Photoshop cs对Cercon CAD/CAM制作的底层冠内部和边缘适合性进行评估,对其加工精度进行评价。方法:选择3名正畸患者拔除的第一前磨牙共计12颗。按全瓷冠要求进行牙体制备,要求向聚合度20°,肩台宽度1mm、120°凹面型,固定制备牙于扫描舱内,扫描其数字化代型图像。以隙料厚度30μm制作氧化锆底层冠,共12个。采用硅橡胶印模复制技术和图像分析系统测量底层冠内部和边缘适合性。结果:底层冠的边缘浮升量小于120μm、内部间隙小于200μm,内部和边缘适合性均达到临床要求。底层冠内部适合性的差异与测量位置有关。统计结果显示样本内部适合性不均匀,远中与近中相对位置间、颊侧与舌侧相对位置间有显著差异(P<0.05)。近远中和颊舌侧间的边缘适合性差异有统计学意(P<0.05),近中与远中间边缘适合性有显著差异(P<0.05),颊侧与舌侧组间边缘适合性差异无统计学意义(P>0.05)。结论:CerconCAD/CAM系统制作的氧化锆底层冠有良好的内部和边缘适合性;Photoshop cs软件是一种评估Cercon CAD/CAM底层冠适合性的简捷有效的方法。

Objective：To evaluate the adaptation of Cercon CAD/CAM copings by Photoshop cs method.Methods：Three patients were selected.Total of 12 teeth which should be extracted due to orthodontic reasons were prepareed.The shoulders were located at 1 mm over the subgingival.The occlusal convergence angles was 20°.The width of the shoulder was 1mm.The shoulder was chamfer margin.The digital were made.12 zirconium dioxide copings were made with 30μm spacer thickness.The internal and marginal fit of copings were measured by Photoshop cs software.Results：The marginal discrepancy of copings is lower than 120μm.The interal gap is lower than 200μm.The internal adaptation of copings is associated with the measurement location.There is statistically significant differences between both mesial,distal marginal gaps and both buccal and lingual internal and marginal gaps（P0.05）.There is statistically signifficant differencs between mesial and distal marginal adaptation （P0.05）.There is no differencs between buccal and lingnal marginal adaptation （P 0.05）.Conclusion：The accuracy by Cercon CAD/CAM system for the marginal and interal fit of zirconium dioxide copings is well.Photoshop cs software is a quick and effective method on evaluating Cercon CAD/CAM coping adaptation.