光学成像粉对全冠数字化模型精度的影响

Effect of optical imaging powder on accuracy of digital model of full crowns

目的研究Cerec inlab MC XL系统光学成像粉对数字化模型精度的影响。方法制备一标准右上第一磨牙全冠预备体模型,并复制8个石膏扫描代型。每个代型采用inEos扫描单元获取喷粉前后的数字化模型,采用inlab3.65软件测量每个数字化模型边缘、肩台、轴面、窝沟、牙尖区域喷粉前后的变化情况。最后采用SAS软件对实验数据进行统计分析。结果数字化模型各区域1周前后的测量值无统计学差异(P>0.05);喷粉后的数字化模型质量较喷粉前好,光学成像粉对数字化模型边缘、肩台、轴面、窝沟、牙尖区域的影响值分别为(0.073±0.042)、(0.106±0.077)、(0.044±0.025)、(0.128±0.060)、(0.102±0.056)mm,各区域影响值比较差异显著(P<0.01)。结论光学成像粉对全冠数字化模型各区域的影响是不同的,对面和肩台的影响大于边缘和轴面,提示不同区域喷粉时要区别对待。

Objective To determine the effect of optical imaging powder on the accuracy of digital model of full crowns in Cerec inlab MC XL system. Methods A upper first right molar in the standard model were prepared, and 8 scanned models made of esthetic-base gypsum were duplicated, of which each model including digital models were digitally imaged by scanning in inEos unit before and after powder spraying. The changing paradigm of each digital model at its marginal area, shoulder area, axial area and pit and fissure of occlusal areas were measured by inlab 3D software （version 3.65 ）. Finally, the results were analyzed statistically by SAS programs. Results No statistical difference was observed between the two reports of the digital model before and after a week （P 〉 0.05 ） in terms of measured values. The resolution of digital model after powder spraying was better than before, and optical imaging powder had certain effect on the model＇ s marginal area, shoulder area, axial area, and pit and fissure of occlusal areas. The floor impact counter of them were 0. 073± 0.042, 0. 106 ± 0. 077, 0. 044 ± 0. 025, 0. 128 ±0. 060 and 0. 102 ± 0.056 mm respectively. Such differences were considered with statistical significance （P 〈 0.01 ）. Conclusion Optical imaging powder has different effect on the accuracy of digital model in different area, which shows stronger on shoulder and oeclusal area than on marginal and axial area. It is suggested that different regional spray powder should be treated differently.