Revilla-León Marta, Ntovas Panagiotis, Barmak Abdul B, Fernández-Estevan Lucía, Agustín-Panadero Rubén, Kois John C
Affiliate Assistant Professor, Graduate Prosthodontics, Department of Restorative Dentistry, School of Dentistry, University of Washington, Seattle, Wash.; Faculty and Director, Research and Digital Dentistry, Kois Center, Seattle, Wash.; and Adjunct Professor, Graduate Prosthodontics, Department of Prosthodontics, School of Dental Medicine, Tufts University, Boston, Mass.
Scientific Affiliate, Department of Operative Dentistry, National and Kapodistrian University of Athens, Greece; and Department of Prosthodontics, School of Dental Medicine, Tufts University, Boston, Mass.
J Prosthet Dent. 2024 Jul 31. doi: 10.1016/j.prosdent.2024.06.023.
Intraoral scanners (IOSs) can be used to record the maxillomandibular relationship at centric relation (CR). The articulated digital scans can be imported into a dental computer-aided design (CAD) program and used to locate centric occlusion (CO); however, the accuracy of the CO recorded by using IOSs and a dental CAD program remains unknown.
The purpose of this clinical study was to compare the position of the CO located by using a conventional method and 4 IOSs combined with a dental CAD program.
A patient volunteered to participate in this study. Conventional diagnostic stone casts were obtained. A facebow record (Kois Dentofacial Analyzer) was used to transfer the maxillary cast into a semi-adjustable articulator (Panadent PCH Articulator). A Kois deprogrammer (KD) was used to record the maxillomandibular relationship at CR and to transfer the mandibular cast into the articulator. Afterwards, CO was located in the articulated casts by removing the incisal pin and using an 8-µm articulating foil. CO was marked in the casts by using a blue articulating paper (control). Three groups were created based on the IOS used: TRIOS 4, iTero Element 5D Plus, i700, and Primescan. In each IOS group, a maxillary and mandibular scan were obtained. The scans were duplicated 10 times. Afterwards, a bilateral occlusal record captured with the KD was used to articulate each pair of duplicated scans. Each articulated specimen was imported into a CAD program (DentalCAD) and CO was virtually located. The teeth contacting at the CO of each specimen were compared with the control group. Categorical data were analyzed by using the chi-squared test (α=.05).
The chi-squared test revealed a significant association between the IOS system and the location of the CO (P=.004). The highest association was found between the TRIOS 4 and CO position, in which 100% of the specimens obtained the same CO position as in the conventional group. The lowest association was found between the i700 and CO position. In the i700 group, 20% of the specimens showed the same CO position as in the control group. A similar outcome was obtained in the iTero and Primescan groups. In both groups, 60% of the specimens demonstrated the same CO position as the control group.
The IOS system used to acquire articulated scans at CR impacted the CO position located by using the evaluated digital methods. The TRIOS 4 system was the only IOS that consistently reproduced the same CO position as the conventional method.
口腔内扫描仪（IOS）可用于记录正中关系（CR）时的上下颌关系。可将关节连接的数字扫描导入牙科计算机辅助设计（CAD）程序并用于确定正中咬合（CO）；然而，使用IOS和牙科CAD程序记录的CO的准确性仍然未知。
本临床研究的目的是比较使用传统方法以及4种IOS与牙科CAD程序相结合来确定的CO的位置。
一名患者自愿参与本研究。获取了传统诊断石膏模型。使用面弓记录（Kois牙面分析仪）将上颌模型转移到半可调式牙合架（Panadent PCH牙合架）中。使用Kois去程序化器（KD）记录CR时的上下颌关系，并将下颌模型转移到牙合架中。之后，通过移除切导针并使用8μm的咬合箔在关节连接的模型中确定CO。使用蓝色咬合纸在模型中标出CO（对照组）。根据所使用的IOS创建了三组：TRIOS 4、iTero Element 5D Plus、i700和Primescan。在每个IOS组中，获取了上颌和下颌扫描。扫描重复10次。之后，使用KD获取的双侧咬合记录来连接每对重复的扫描。将每个关节连接的标本导入CAD程序（DentalCAD）并虚拟确定CO。将每个标本在CO处接触的牙齿与对照组进行比较。使用卡方检验分析分类数据（α = 0.05）。
卡方检验显示IOS系统与CO的位置之间存在显著关联（P = 0.004）。在TRIOS 4与CO位置之间发现的关联最高，其中100%的标本获得了与传统组相同的CO位置。在i700与CO位置之间发现的关联最低。在i700组中，20%的标本显示出与对照组相同的CO位置。在iTero和Primescan组中获得了类似的结果。在这两组中，60%的标本显示出与对照组相同的CO位置。
用于在CR获取关节连接扫描的IOS系统影响了使用评估的数字方法确定的CO位置。TRIOS 4系统是唯一能始终如一地再现与传统方法相同的CO位置的IOS。
