Trueness of Intra-Oral Scanners Compared to an Extra-Oral Scanner for Scanning of Mandibular Edentulous Impressions

Overview

the relative accuracy of different intraoral scanner types specifically for capturing the complex morphology of edentulous arches, including peripheral borders and mobile tissues, remains an area of investigation, with conflicting reports in the literature. The purpose of this study is to compare the accuracy of different intraoral scanners with a laboratory scanner for digitizing impressions of edentulous mandible. Completely edentulous patients will be gathered; final impressions will be taken for them using zinc oxide \& eugenol impression material then they will be scanned with intra oral and extra oral scanners for indirect digitalization. Scans will be superimposed and compared using a software program for analysis for accuracy in the form of trueness

completely edentulous patients will be recruited. Study procedures: Custom trays will be fabricated and checked for extension, and then definitive impressions will be made with type-1 low fusing impression compound (Tracing sticks; Kemdent, UK) for border molding and zinc oxide eugenol impression paste (Cavex Holland B.N) for the impression. Reference markers will be placed on the impressions in anterior and posterior ridge areas. The indirect digitalization of impressions will be made with two different Intraoral scanning devices and a laboratory scanner. * Intra oral scanners are: 1. Aoralscan (Shining 3D Tech. Co., Ltd. Hangzhou, China): structured light-optical triangulation technology. 2. MEDIT i600 (Medit Corp. Seoul, South Korea): structured light-3d-in-motion video technology. * Extra oral scanner: UP3D. Scans will be exported as standard tessellation language (STL) files. The STL files then will be compared using a 3D analysis software program for analysis. For "trueness" measurements every STL file of each experimental group will be superimposed to the extra oral scan.