Elawady Dina Mohamed Ahmed, Ibrahim Wafaa Ibrahim, Ghanem Radwa Gamal, Osman Reham Bassuni
Department of Prosthodontics, Faculty of Dentistry, MSA University, Giza, Egypt.
Department of Prosthodontics, Faculty of Oral and Dental Medicine, Delta University for Science and Technology, Dakahlia, Egypt.
J Adv Prosthodont. 2024 Aug;16(4):201-211. doi: 10.4047/jap.2024.16.4.201. Epub 2024 Aug 20.
The aim of this prospective clinical study was to compare the influence of palatal vault forms on accuracy and speed of intraoral (IO) scans in completely edentulous cases.
Based on the palatal vault form, participants were divided into three equal groups (n = 10 each); Class I: moderate; Class II: deep; Class III: flat palatal vault. A reference model was created for each patient using polyvinylsiloxane impression material. The poured models were digitized using an extraoral scanner. The resultant data were imported as a solid CAD file into 3D analysis software (GOM Inspect 2018; Gom GmbH, Braunschweig, Germany) and aligned using the software's coordinate system to determine its X, Y, and Z axes. Five digital impressions (DIs) of maxilla were captured for each patient using an intraoral scanner (TRIOS; 3Shape A/S, Copenhagen, Denmark) and the resultant Standard Tessellation Language (STL) scan files served as test models. Trueness was evaluated by calculating arithmetic mean deviation (AMD) of the vault area between reference and test files while precision was evaluated by calculating AMD between captured scans to measure repeatability of scan acquisition. The scan time taken for each participant was also recorded.
There was no significant difference in trueness and precision among the groups ( = .806 and .950, respectively). Average scan time for Class I and III palatal vaults was 1 min 13 seconds and 1 min 37 seconds, respectively, while class II deep palatal vaults showed the highest scan time of 5 mins.
Palatal vault form in edentulous cases has an influence on scan time. However, it does not have a substantial impact on the accuracy of the acquired scans.
本前瞻性临床研究旨在比较完全无牙颌病例中腭穹窿形态对口内（IO）扫描准确性和速度的影响。
根据腭穹窿形态，将参与者分为三组，每组人数相等（每组n = 10）；I类：中度；II类：深度；III类：扁平腭穹窿。使用聚乙烯基硅氧烷印模材料为每位患者制作一个参考模型。将灌注后的模型用口外扫描仪进行数字化处理。所得数据作为实体CAD文件导入3D分析软件（GOM Inspect 2018；德国不伦瑞克市的Gom GmbH公司），并使用该软件的坐标系进行对齐，以确定其X、Y和Z轴。使用口内扫描仪（TRIOS；丹麦哥本哈根的3Shape A/S公司）为每位患者采集五次上颌的数字印模（DI），所得的标准镶嵌语言（STL）扫描文件用作测试模型。通过计算参考文件和测试文件之间腭穹窿区域的算术平均偏差（AMD）来评估准确性，同时通过计算采集的扫描之间的AMD来评估精度，以测量扫描采集的重复性。还记录了每位参与者的扫描时间。
各组之间在准确性和精度方面无显著差异（分别为 = .806和.950）。I类和III类腭穹窿的平均扫描时间分别为1分13秒和1分37秒，而II类深腭穹窿的扫描时间最长，为5分钟。
无牙颌病例中的腭穹窿形态对扫描时间有影响。然而，它对采集扫描的准确性没有实质性影响。
