Assistant Professor, Department of Prosthetic Dentistry, Faculty of Dentistry, University of Istanbul Okan, Istanbul, Turkey.
Associate Professor, Department of Prosthetic Dentistry, Faculty of Dentistry, University of Istanbul Okan, Istanbul, Turkey.
J Prosthet Dent. 2022 Aug;128(2):187-194. doi: 10.1016/j.prosdent.2020.12.007. Epub 2021 Feb 6.
The digital scan accuracy of different intraoral scanners (IOSs) for long-span fixed prosthesis and the effect of the starting quadrant on accuracy is unclear.
The purpose of this in vitro study was to evaluate the accuracy of 6 IOSs for complete-arch and prepared teeth digitally isolated from the complete-arch and to determine the effect of the starting quadrant on accuracy.
A maxillary model containing bilaterally prepared canines, first molar teeth, and edentulous spans between the prepared teeth was used. The model was scanned by using a highly accurate industrial scanner to create a digital reference data set. Six IOSs were evaluated: TRIOS, iTero, Planmeca Emerald, Cerec Omnicam, Primescan, and Virtuo Vivo. The model was scanned 10 times with each IOS by 1 operator according to the protocols described by the manufacturers. Five scans were made starting from the right quadrant (ScanR), followed by 5 scans starting from the left quadrant (ScanL). All data sets were obtained in standard tessellation language (STL) file format and were used to evaluate accuracy (trueness and precision) with a 3D analyzing software program (Geomagic Studio 12; 3D Systems) by using a best-fit alignment. The prepared teeth were digitally isolated from the complete-arch and evaluated with the analyzing software program. The Kruskal-Wallis and Mann-Whitney U statistical tests were used to detect differences for trueness and precision (α=.05).
Statistically significant differences were found regarding IOSs (P<.003) and scanning sequence (P<.05). The TRIOS showed the best trueness for the complete-arch, but not statistically different from Primescan, Virtuo Vivo, and iTero (P>.003). The lowest median values for precision of the complete-arch were also found using TRIOS, but no significant difference was found among the scanners (P>.003). In terms of trueness and precision, Primescan had the best accuracy for preparations. Emerald showed significant differences depending on the scanning sequence for complete-arch accuracy. ScanR for trueness (P=.021) and ScanL for precision (P=.004) showed improved results. However, Emerald, TRIOS, and Virtuo Vivo showed statistically significant differences in precision of preparations depending on scanning sequence. ScanL deviated less than ScanR when scanned with TRIOS (P=.025) and Emerald (P=.004), and the opposite with Virtuo Vivo (P=.008). In terms of preparations trueness, no significant difference was found between the ScanR and ScanL of any IOS (P>.05).
Based on this in vitro study, the accuracy of the complete-arch and prepared teeth differed according to the IOS and scanning sequence.
不同口内扫描仪（IOS）对长跨度固定修复体的数字扫描准确性以及起始象限对准确性的影响尚不清楚。
本体外研究的目的是评估 6 种 IOS 对完整牙弓和从完整牙弓中分离出来的预备牙的数字化准确性，并确定起始象限对准确性的影响。
使用包含双侧预备的尖牙、第一磨牙和预备牙之间无牙弓的上颌模型。使用高精度工业扫描仪对模型进行扫描，以创建数字参考数据集。评估了 6 种 IOS：TRIOS、iTero、Planmeca Emerald、Cerec Omnicam、Primescan 和 Virtuo Vivo。由同一位操作员根据制造商描述的协议，使用每种 IOS 对模型进行了 10 次扫描。从右侧象限（ScanR）开始进行 5 次扫描，然后从左侧象限（ScanL）开始进行 5 次扫描。所有数据集均以标准三角测量语言（STL）文件格式获得，并使用 3D 分析软件程序（Geomagic Studio 12；3D Systems）通过最佳拟合对齐来评估准确性（准确性和精密度）。使用分析软件程序从完整牙弓中分离出预备牙并进行评估。使用 Kruskal-Wallis 和 Mann-Whitney U 统计检验来检测准确性（准确性和精密度）的差异（α=.05）。
在 IOS（P<.003）和扫描顺序（P<.05）方面均发现具有统计学意义的差异。TRIOS 对完整牙弓的准确性最好，但与 Primescan、Virtuo Vivo 和 iTero 相比没有统计学差异（P>.003）。TRIOS 也获得了完整牙弓精度的最低中位数，但扫描仪之间没有显著差异（P>.003）。就准确性而言，Primescan 对预备牙的准确性最好。 Emerald 显示出根据完整牙弓精度的扫描顺序的显著差异。ScanR 的准确性（P=.021）和 ScanL 的精密度（P=.004）显示出改进的结果。然而， Emerald、TRIOS 和 Virtuo Vivo 的预备牙精度根据扫描顺序显示出统计学上的显著差异。当使用 TRIOS 和 Emerald 扫描时，ScanL 的偏差小于 ScanR（P=.025 和 P=.004），而当使用 Virtuo Vivo 扫描时则相反（P=.008）。在预备牙的准确性方面，任何 IOS 的 ScanR 和 ScanL 之间均未发现统计学差异（P>.05）。
基于这项体外研究，完整牙弓和预备牙的准确性根据 IOS 和扫描顺序而有所不同。
