结构设计对三维打印树脂牙列模型尺寸稳定性的影响

Effects of structural design on dimensional stability of 3D printed maxillary resin models

目的 研究结构设计对三维打印上颌树脂牙列模型远期尺寸稳定性的影响。方法 使用模型扫描仪扫描上颌标准石膏牙列模型,导入3Shape软件中设计两组不同结构设计的牙列模型,分别为马蹄形实心模型和马蹄形空心模型。使用三维打印机每组打印5个树脂牙列模型。在打印完成后第1、2、3、5、7、14、21、28天,使用模型扫描仪对其进行扫描,并将扫描文件保存为“.stl”文件格式,导入Geomagic软件中与相应的模型设计文件进行偏差分析。结果 马蹄实心设计的打印模型组28 d内的偏差范围为(31.41±4.29)μm到(36.38±3.99)μm,马蹄空心组28 d内的偏差范围为(57.36±7.66)μm到(97.64±27.14)μm。两种结构设计的三维打印牙列树脂模型偏差均小于100μm。马蹄实心组打印完成28 d内的精度与第1天对比均无统计学差异(P>0.05);马蹄空心组打印后第7天开始,精度与第1天对比存在统计学差异(P<0.05),随着存储时间的延长牙列模型的形变变得明显。结论 马蹄实心结构设计的打印树脂模型长期尺寸稳定性良好。马蹄空心结构设计的打印树脂模型7 d内尺寸稳定性良好。

Objective To investigate the effect of different structural designs on dimensional stability of 3D printed maxillary resin models.Methods A model scanner was used to scan the standard gypsum dentition model of the upper jaw.Two sets of models with different structural types were designed in the denture design software,including horseshoe-shaped solid model and horseshoe-shaped hollow model.A 3D printer was used to print five resin models each group.On day 1,2,3,5,7,14,21,and 28 after printing,the models were scanned with a 3D model scanner.Saved as the “.stl” file format,the scanned files of the printed models were then performed deviation analysis with the corresponding model design files in Geomagic software.Results The deviation range of the horseshoe-shaped solid models within 28 days was(31.41±4.29)μm to(36.38±3.99)μm.The deviation range of the horseshoe-shaped hollow models within 28 days was(57.36±7.66)μm to(97.64±27.14)μm.The deviation of the 3D printed resin models made with two structural designs was less than 100 μm.There was no statistical difference between the accuracy of the horseshoe solid group within 28 days of printing and the first day(P>0.05).There was a statistical difference between the accuracy of the 7th day after the printing of the horseshoe hollow group and the first day(P<0.05).With the extension of storage time,the deformation of the horseshoe-shaped hollow models became more and more obvious.Conclusion 3D-printed resin dental models with the horseshoe solid structure design have excellent long-term dimensional stability.The resin models of the hollow design of the horseshoe structure have good dimensional stability within 7 days after printing.