Professor, Department of Prosthodontics, Institute of Odontology, Faculty of Medicine, Vilnius University, Vilnius, Lithuania.
Assistant Professor, Department of Prosthodontics, Institute of Odontology, Faculty of Medicine, Vilnius University, Vilnius, Lithuania.
J Prosthet Dent. 2023 Jul;130(1):111-118. doi: 10.1016/j.prosdent.2021.09.032. Epub 2021 Nov 17.
The effect of additional reference objects on the accuracy of different intraoral scanners for partially and completely edentulous patients has not been investigated sufficiently.
The purpose of this in vitro study was to evaluate the effect of an additional reference object in the form of additional artificial landmarks on the trueness and precision of different intraoral scanners in partially and completely edentulous areas.
Partially and completely edentulous models with 2 and 4 implants (BLT, RC, Institut Straumann AG), respectively, were used in the study. For the digital scan, scan bodies (CARES Mono Scanbody) were attached, and reference data obtained by using industrial scanners. Ten digital scans of the same model were made with each intraoral scanner: PRIMESCAN, TRIOS 3, TRIOS 4, Carestream 3600, and Medit. Then, additional artificial landmarks were attached, and 10 more intraoral scans were made with each device. Computer-aided design files of the scan bodies were aligned to obtain 3-dimensional surfaces with reference and test scanners. Trueness and precision of distance, angulations, and vertical shift between scan bodies were estimated. The Mann-Whitney Wilcoxon or Student 2-sample t test was applied to estimate statistically significant differences between groups (α=.05).
In the partially edentulous model, distance trueness mean ±standard deviation values ranged from -46.7 ±15.4 μm (TRIOS 3) to 392.1 ±314.3 μm (Medit) in models without additional artificial landmarks. When additional artificial landmarks were applied, trueness of distance mean ±standard deviation values ranged between -35 ±13 μm (TRIOS 4) and 117.7 ±232.3 μm (CARESTREAM). Trueness mean ±standard deviation values of angulation varied from -0.0 ±0.5 degrees (CARESTREAM) to 0.2 ±0.0 degrees (PRIMESCAN) without additional artificial landmarks and from 0.0 ±0.2 degrees (TRIOS 3) to 0.4 ±0.5 degrees (CARESTREAM) with additional artificial landmarks. Vertical shift trueness measurements varied from -108 ±47.1 μm (TRIOS 4) to 107.2 ±103.5 μm (Medit) without additional artificial landmarks and from -15.0 ±45.0 μm (CARESTREAM) to -86.9 ±42.1 μm (TRIOS 4) with additional artificial landmarks. The additional artificial landmark technique improved the trueness of all measured parameters for the 5 tested intraoral scanners. No statistically significant differences were found among models with or without additional artificial landmarks, except for Medit in all parameters and PRIMESCAN in angle measurements (P<.05). The best precision for distance was found with TRIOS 3 and with PRIMESCAN for angulation and vertical shift. Larger deviations were observed in the completely edentulous situation. The effect of additional artificial landmarks was limited when the accuracy parameters of digital scans were considered.
Scans with and without additional artificial landmarks of partially edentulous conditions scanned by any of the intraoral scanners tested did not influence precision and trueness, except for Medit i500 in the distance and vertical shift parameters and CARESTREAM3600 in vertical shift. Precision and trueness of digital scans of completely edentulous areas were affected, except for Medit i500 for distance, PRIMESCAN and TRIOS 4 for angle, and all systems except TRIOS 4 for vertical shift precision.
额外参考物体对部分和完全无牙患者不同口内扫描仪准确性的影响尚未得到充分研究。
本体外研究的目的是评估额外参考物体（即额外人工地标）对部分和完全无牙区域中不同口内扫描仪准确性和精度的影响。
研究中使用了带有 2 个和 4 个植入物（BLT、RC、 Institut Straumann AG）的部分和完全无牙模型。对于数字扫描，将扫描体（CARES Mono Scanbody）附着，并使用工业扫描仪获得参考数据。使用每个口内扫描仪对同一模型进行 10 次数字扫描：PRIMESCAN、TRIOS 3、TRIOS 4、Carestream 3600 和 Medit。然后，将额外的人工地标附着，并使用每个设备再进行 10 次口内扫描。使用计算机辅助设计文件对齐扫描体，以获得参考和测试扫描仪的三维表面。估计扫描体之间的距离、角度和垂直位移的准确性和精度。应用曼-惠特尼 Wilcoxon 或学生 2 样本 t 检验来估计组之间的统计学显著差异（α=.05）。
在部分无牙模型中，没有附加人工地标时，距离准确性的平均值±标准差范围为-46.7±15.4μm（TRIOS 3）至 392.1±314.3μm（Medit）。当应用额外的人工地标时，距离准确性的平均值±标准差范围在-35±13μm（TRIOS 4）和 117.7±232.3μm（CARESTREAM）之间。角度准确性的平均值±标准差范围从-0.0±0.5 度（CARESTREAM）到 0.2±0.0 度（PRIMESCAN），没有附加人工地标，从 0.0±0.2 度（TRIOS 3）到 0.4±0.5 度（CARESTREAM），有附加人工地标。垂直位移准确性的测量值从-108±47.1μm（TRIOS 4）到 107.2±103.5μm（Medit），没有附加人工地标，从-15.0±45.0μm（CARESTREAM）到-86.9±42.1μm（TRIOS 4），有附加人工地标。额外的人工地标技术提高了 5 种测试口内扫描仪所有测量参数的准确性。除了 Medit 在所有参数和 PRIMESCAN 在角度测量中的差异有统计学意义（P<.05）外，没有在模型之间发现统计学显著差异。在距离方面，TRIOS 3 的精度最好，在角度和垂直位移方面，PRIMESCAN 的精度最好。在完全无牙情况下观察到更大的偏差。当考虑数字扫描的准确性参数时，附加人工地标对扫描的精度和准确性的影响是有限的。
在测试的任何口内扫描仪中，部分无牙条件下有和没有附加人工地标扫描的精度和准确性没有影响，除了 Medit i500 在距离和垂直位移参数以及 CARESTREAM3600 在垂直位移方面。完全无牙区域的数字扫描精度和准确性受到影响，除了 Medit i500 在距离方面，PRIMESCAN 和 TRIOS 4 在角度方面，以及除了 TRIOS 4 在垂直位移精度方面的所有系统。
