Private practice, Lisbon, Portugal; Invited Lecturer, Department of Oral Rehabilitation, Faculty of Dental Medicine, University of Lisbon, Lisbon, Portugal.
Private practice, Lisbon, Portugal; Invited Lecturer, Department of Oral Rehabilitation, Faculty of Dental Medicine, University of Lisbon, Lisbon, Portugal.
J Prosthet Dent. 2024 Jul;132(1):172-177. doi: 10.1016/j.prosdent.2023.07.008. Epub 2023 Aug 22.
Digital methods such as intraoral scanners for recording the location of implants supporting complete arch prostheses have limitations. Photogrammetry devices should be able to digitize implant positions accurately, but standardized comparisons between different digital acquisition methods are lacking.
The purpose of this in vitro study was to compare the repeatability of different digital acquisition methods for complete arch prostheses supported by 6 and 4 implants.
A master cast was created with 6 and 4 dental implants with multiunit abutments to obtain the master digital casts. The evaluated devices were the industrial high-resolution 12-megapixel scanner (reference) Atos Compact Scan 12M (GOM), the laboratory scanners D2000 (3Shape A/S) and S900 Arti (Zirkonzahn), the photogrammetry devices iCam (iMetric4D) and PIC (PIC Dental), and the intraoral scanners TRIOS 3 (3Shape A/S) and iTero Element 5D (Align Technology). The resulting files were imported to a computer-aided design software program (exocad GmbH) to obtain the implant replicas as standard tessellation language (STL) files. These files were imported into a software program (Geomagic Control X) and superimposed per group through the best-fit algorithm to determine repeatability, defined as the closeness of agreement between each group's scanned results as root mean square (RMS) values. The normality of distribution was tested by the Shapiro-Wilk normality test, and the Kruskal-Wallis test with adjustment with the Bonferroni correction method was used accordingly (α=.05).
The repeatability means and 95% confidence intervals for the 4 implant scans were: 1.07 µm (0.86; 1.29) for GOM, 2.05 µm (1.89; 2.21) for D2000, 3.61 µm (3.23; 3.99) for S900, 7.01 µm (6.11; 7.91) for iCam, 5.18 µm (4.6; 5.76) for PIC, 20.52 µm (18.33; 22.72) for TRIOS 3, and 20.5 µm (17.37; 23.63) for iTero. Statistically significant differences were found between devices, except for iCam versus PIC, GOM versus S900, iCam versus D2000, PIC versus D2000, and TRIOS 3 versus iTero. The repeatability means and 95% confidence intervals for the 6 implant groups were: 1.36 µm (1.08; 1.65) for GOM, 3.17 µm (3.01; 3.33) for D2000, 2.15 µm (2.04; 2.25) for S900, 8.67 µm (8.06; 9.28) for iCam, 13.88 µm (12.62; 15.14) for PIC, 40.32 µm (36.29; 44.36) for TRIOS 3, and 38.86 µm (34.01; 43.71) for iTero. Statistically significant differences were detected between devices, except for S900 versus GOM, PIC versus iCam, and iTero versus TRIOS 3.
The results suggest that photogrammetry could be a suitable alternative for recording implant locations of complete arch prostheses supported by 4 or 6 implants, with better repeatability than intraoral scanners. Increasing the number of implants decreased the repeatability of every device tested except the laboratory scanners.
用于记录全口义齿修复体支持的种植体位置的数字方法，如口内扫描仪，存在局限性。摄影测量设备应该能够准确地数字化种植体位置，但缺乏不同数字采集方法之间的标准化比较。
本体外研究的目的是比较 6 个和 4 个种植体支持的全口义齿修复体的不同数字采集方法的重复性。
使用带有多单位基台的 6 个和 4 个牙种植体制作母模，以获得母模数字模型。评估的设备包括工业高分辨率 1200 万像素扫描仪（参考）Atos Compact Scan 12M（GOM）、实验室扫描仪 D2000（3Shape A/S）和 S900 Arti（Zirkonzahn）、摄影测量设备 iCam（iMetric4D）和 PIC（PIC Dental）以及口内扫描仪 TRIOS 3（3Shape A/S）和 iTero Element 5D（Align Technology）。将得到的文件导入计算机辅助设计软件程序（exocad GmbH）中，以获得标准 tessellation language（STL）文件的种植体复制品。这些文件被导入到一个软件程序（Geomagic Control X）中，并通过最佳拟合算法对每组进行叠加，以确定重复性，定义为每组扫描结果的接近程度，以均方根（RMS）值表示。通过 Shapiro-Wilk 正态性检验测试分布的正态性，然后使用 Kruskal-Wallis 检验和 Bonferroni 校正方法进行调整（α=0.05）。
4 个种植体扫描的重复性平均值和 95%置信区间分别为：GOM 为 1.07μm（0.86；1.29），D2000 为 2.05μm（1.89；2.21），S900 为 3.61μm（3.23；3.99），iCam 为 7.01μm（6.11；7.91），PIC 为 5.18μm（4.6；5.76），TRIOS 3 为 20.52μm（18.33；22.72），iTero 为 20.5μm（17.37；23.63）。除了 iCam 与 PIC、GOM 与 S900、iCam 与 D2000、PIC 与 D2000 以及 TRIOS 3 与 iTero 之间没有统计学差异外，设备之间存在统计学显著差异。6 个种植体组的重复性平均值和 95%置信区间分别为：GOM 为 1.36μm（1.08；1.65），D2000 为 3.17μm（3.01；3.33），S900 为 2.15μm（2.04；2.25），iCam 为 8.67μm（8.06；9.28），PIC 为 13.88μm（12.62；15.14），TRIOS 3 为 40.32μm（36.29；44.36），iTero 为 38.86μm（34.01；43.71）。除了 S900 与 GOM、PIC 与 iCam 以及 iTero 与 TRIOS 3 之间没有统计学差异外，设备之间存在统计学显著差异。
结果表明，摄影测量技术可能是一种适合记录 4 个或 6 个种植体支持的全口义齿修复体种植体位置的替代方法，其重复性优于口内扫描仪。增加种植体的数量除了实验室扫描仪外，降低了每个测试设备的重复性。
