Asavanant Natalie, Yang Chao-Chieh, AlQallaf Hawra, Zandinejad Amirali, Morton Dean, Nagai Toshiki, Lin Wei-Shao
Asavanant Dental Clinic, Bangkok, Thailand.
Department of Prosthodontics, Indiana University School of Dentistry, Indianapolis, Indiana, USA.
J Prosthodont. 2025 Aug;34(7):741-748. doi: 10.1111/jopr.14084. Epub 2025 Jun 19.
To evaluate the impact of different complete-arch digital scanning techniques on the passive fit of computer-aided design and computer-aided manufacturing (CAD-CAM) verification devices.
A mandibular master cast with four multiunit abutment implant analogs was used as the basis for fabricating verification devices through three impression techniques. Group 1 employed a conventional open-tray impression technique using polyvinyl siloxane material, Group 2 utilized digital scans of splinted scanbodies reinforced with a light-polymerizing acrylic resin and metal mesh, and Group 3 applied digital scans of reverse scanbodies connected to a passively fitting interim prosthesis. A total of 60 CAD-CAM verification devices were fabricated, including 10 milled and 10 3D-printed devices across the three groups. The misfit of verification devices was assessed using visual inspection, tactile sensation, and a one-screw test, with any disagreements between the two primary examiners resolved by a third evaluator. Agreement between the clinicians was assessed using crosstabs, kappa statistics, and percent agreement separately for the visual and tactile evaluations. The percentage of misfits was calculated for each group and compared between groups using Fisher's exact tests (α = 0.05).
Milled verification devices exhibited superior passive fit compared to 3D-printed devices across all groups. The Group 1 conventional open-tray technique with milled devices achieved a misfit percentage of 0%, significantly outperforming other groups. Group 3 reverse scanbodies with milled devices followed with a 20% misfit rate, while Group 2 splinted scanbodies with auxiliary features and milled devices showed the highest misfit rate at 60%. Among 3D-printed devices, Group 1 had the lowest misfit rate at 50%, followed by Group 3 at 60%, and Group 2 at 80%. The agreement between examiners was substantial, with a kappa statistic of 0.77 and 88% consistency. Statistical analysis revealed significant differences in misfit rates, highlighting the advantages of conventional methods and milled devices in achieving superior fit.
The conventional splinted open-tray impression technique, combined with milled verification devices, demonstrated superior fit and outperformed other impression and manufacturing techniques. The reverse scanbody protocol performed better than splinted scanbodies with auxiliary features, although it still showed variability. Conversely, 3D-printed verification devices demonstrated higher misfit rates, limiting their clinical applicability for verifying implant positions in complete-arch prostheses.
评估不同的全牙弓数字扫描技术对计算机辅助设计与计算机辅助制造（CAD-CAM）验证装置被动适合性的影响。
使用带有四个多单位基牙种植体代型的下颌主模型，通过三种印模技术制作验证装置。第1组采用使用聚硅氧烷材料的传统开放式托盘印模技术，第2组利用用光聚合丙烯酸树脂和金属网增强的夹板式扫描体进行数字扫描，第3组应用连接到被动适合的临时修复体的反向扫描体进行数字扫描。共制作了60个CAD-CAM验证装置，每组包括10个铣削制作的和10个3D打印制作的装置。使用目视检查、触觉感受和单螺钉测试评估验证装置的不适合情况，两位主考官之间的任何分歧由第三位评估者解决。分别使用交叉表、kappa统计量和百分比一致性评估临床医生之间在视觉和触觉评估方面的一致性。计算每组的不适合百分比，并使用Fisher精确检验（α = 0.05）在组间进行比较。
在所有组中，铣削制作的验证装置比3D打印制作的装置表现出更好的被动适合性。第1组使用铣削制作装置的传统开放式托盘技术的不适合百分比为零，明显优于其他组。第3组使用铣削制作装置的反向扫描体的不适合率为20%，而第2组具有辅助特征的夹板式扫描体并使用铣削制作装置的不适合率最高，为60%。在3D打印制作的装置中，第1组的不适合率最低，为50%，其次是第3组，为60%，第2组为80%。考官之间的一致性较高，kappa统计量为0.77，一致性为88%。统计分析显示不适合率存在显著差异，突出了传统方法和铣削制作装置在实现更好适合性方面的优势。
传统的夹板式开放式托盘印模技术与铣削制作的验证装置相结合，显示出更好的适合性，优于其他印模和制作技术。反向扫描体方案比具有辅助特征的夹板式扫描体表现更好，尽管仍存在变异性。相反，3D打印制作的验证装置显示出更高的不适合率，限制了它们在全牙弓修复体中验证种植体位置的临床适用性。
