Department of Prosthodontics, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
Department of Prosthodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
J Med Life. 2023 May;16(5):736-742. doi: 10.25122/jml-2023-0103.
This study aimed to examine the effect of inter-dental abutment distance on the accuracy of digital and conventional impression methods. Five maxillary and mandibular models were prepared with different inter-dental abutment distances. Digital scans were obtained using an extraoral laboratory scanner as reference data. Each group was scanned 8 times using the intra-oral scanner for the digital method. For the conventional impression method, 8 additional silicone impression material was used to generate the stone casts from each group. Then casts were scanned. In the next step, stereolithography (STL) data was exported from the scans. The STL files were super-imposed on the reference scans using 3shape dental designer software to make the measurement. Kolmogorov-Smirnoff was used to determine if the data were normally distributed. In the digital impression method, as the abutment distance increased, the accuracy decreased. Various inter-dental abutment distances in digital groups showed significant differences (p=0.016) in impression accuracy, while the difference among conventional groups was not statistically significant (p=0.822). In the digital method, the mean inter-dental abutment between the 4-5 and 3-7 groups, 4-6 and 3-7 groups had a significant difference (p<0.05). However, the conventional method revealed no significant differences (p>0.05) between groups. In conclusion, when the inter-dental abutment distance exists and is surrounded by soft tissue, the possibility of error in the digital impression method is higher than in the conventional impression method.
本研究旨在探讨牙间支抗距离对数字和传统印模方法准确性的影响。制备了具有不同牙间支抗距离的 5 个上颌和下颌模型。使用口腔外实验室扫描仪获取数字扫描作为参考数据。使用口腔内扫描仪对每个组进行 8 次扫描，用于数字方法。对于传统印模方法，使用 8 个额外的硅橡胶印模材料从每组生成石铸模。然后对铸模进行扫描。在下一步中，从扫描中导出立体光刻 (STL) 数据。使用 3Shape 牙科设计软件将 STL 文件叠加到参考扫描上进行测量。使用 Kolmogorov-Smirnoff 确定数据是否呈正态分布。在数字印模方法中，随着牙间支抗距离的增加，准确性降低。数字组中各种牙间支抗距离的印模准确性显示出显著差异（p=0.016），而传统组之间的差异无统计学意义（p=0.822）。在数字方法中，4-5 组和 3-7 组、4-6 组和 3-7 组之间的牙间支抗距离存在显著差异（p<0.05）。然而，传统方法在组间没有显示出显著差异（p>0.05）。总之，当牙间支抗距离存在且被软组织包围时，数字印模方法的误差可能性高于传统印模方法。
