Jiang Yuhao, Long Hu, Soo Suet Yeo, Mavani Hetal, Tew In Meei
Department of Restorative Dentistry, The National University of Malaysia, Kuala Lumpur, MYS.
Department of Orthodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, CHN.
Cureus. 2024 Jun 29;16(6):e63471. doi: 10.7759/cureus.63471. eCollection 2024 Jun.
The high cost of intraoral scanners (IOS) for complete-arch scans makes them less accessible for many dental practitioners. As a viable alternative, smartphone scanner applications (SMP) provide comparable scanning capabilities at a significantly low cost. However, there is limited data on the accuracy of SMP, especially when used in various smartphone positions. This study aimed to compare the three-dimensional (3D) and linear accuracy of complete-arch scans acquired by an IOS and SMP (KIRI Engine, KIRI Innovations, Guangdong, China) at three shooting angles (0°, 45°, and 90° for SMP_3A) and two shooting angles (30° and 60° for SMP_2A).
A stone dental cast was scanned with a laboratory scanner as a reference, with 11 scans performed by an IOS, SMP_2A, and SMP_3A. In 3D analysis, trueness and precision were evaluated through superimposition with the reference scan and within each group, respectively, using the best-fit algorithm of Geomagic Wrap software (3D Systems, Inc., Rock Hill, SC). Trueness in linear discrepancy was assessed by comparing the occlusal-cervical and mesiodistal dimensions of reference teeth (canine, premolar, and molar), intercanine width, and intermolar width on the digital casts to measurements of the stone cast, while precision was measured using the coefficient of variance. Differences between groups were analyzed using the Friedman test, followed by the Dunn-Bonferroni post hoc test with a significance level set at 0.05.
IOS exhibited significantly lower trueness than SMP_2A (p = 0.003) with significantly greater width discrepancies on canines (p = 0.001) and molars (p < 0.001). Discrepancy patterns differed among the three scanning methods. The IOS showed greater discrepancies on the occlusal surfaces of posterior teeth. While SMP_3A demonstrated higher variation on the palatal surfaces and interproximal areas of posterior teeth. For precision, SMP_3A (p = 0.028) and SMP_2A (p = 0.003) showed a significantly lower precision in 3D analysis, but a comparable reproducibility in linear measurement to IOS.
TRIOS IOS (3Shape, Copenhagen, Denmark) exhibited lower trueness in 3D and linear accuracy analyses for complete-arch scans. The positions of the smartphone significantly enhanced trueness at the undercut region. SMP_2A and SMP_3A can be a potential alternative for precise linear measurement in complete-arch scans with selective use.
口腔内扫描仪（IOS）用于全牙弓扫描的成本高昂，这使得许多牙科从业者难以使用。作为一种可行的替代方案，智能手机扫描仪应用程序（SMP，中国广东KIRI创新公司的KIRI Engine）以显著较低的成本提供了相当的扫描能力。然而，关于SMP准确性的数据有限，尤其是在各种智能手机位置使用时。本研究旨在比较IOS和SMP（SMP_3A的三个拍摄角度为0°、45°和90°，SMP_2A的两个拍摄角度为30°和60°）在三个拍摄角度下获取的全牙弓扫描的三维（3D）和线性准确性。
用实验室扫描仪扫描石膏牙模作为参考，IOS、SMP_2A和SMP_3A分别进行11次扫描。在3D分析中，使用Geomagic Wrap软件（3D Systems公司，南卡罗来纳州罗克希尔）的最佳拟合算法，通过与参考扫描叠加以及在每组内分别评估准确性和精密度。通过比较数字牙模上参考牙齿（尖牙、前磨牙和磨牙）的咬合-颈缘和近远中尺寸、尖牙间宽度和磨牙间宽度与石膏牙模的测量值来评估线性差异的准确性，同时使用变异系数测量精密度。使用Friedman检验分析组间差异，随后进行Dunn-Bonferroni事后检验，显著性水平设定为0.05。
IOS的准确性显著低于SMP_2A（p = 0.003），尖牙（p = 0.001）和磨牙（p < 0.001）的宽度差异显著更大。三种扫描方法的差异模式不同。IOS在后牙咬合面的差异更大。而SMP_3A在后牙腭面和邻面区域表现出更高的变异性对于精密度，SMP_3A（p = 0.028）和SMP_2A（p = 0.003）在3D分析中显示出显著较低的精密度，但在与IOS的线性测量中具有相当的再现性。
TRIOS IOS（丹麦哥本哈根3Shape公司）在全牙弓扫描的3D和线性准确性分析中表现出较低的准确性。智能手机的位置显著提高了倒凹区域的准确性。SMP_2A和SMP_3A在选择性使用的全牙弓扫描中可以作为精确线性测量的潜在替代方案。
