Accuracy analysis of complete-arch digital scans in edentulous arches when using an auxiliary geometric device

Abstract Statement of problem Obtaining reliable digital scans of edentulous patients is challenging because of the absence of anatomic landmarks/geometric variations along the dental arch. Whether adding an auxiliary geometric device (AGD) will improve scanning is unclear. Purpose The purpose of this in vitro study was to analyze the accuracy of complete-arch digital scans of completely edentulous arches by placing a consumable AGD. Material and methods A stainless-steel model of the maxilla of a completely edentulous arch with 4 implants was built. The model was scanned using a reference industrial scanner as the control and using 3 intraoral scanners (True Definition [3M ESPE], TRIOS 3 [3Shape A/S], and iTero [Align Technology, Inc]). Each intraoral scanner was used 10 times without the AGD in place and 10 more times with the AGD fixed on the model. Accuracy in terms of trueness and precision was established by comparing 5 reference distances with or without the AGD in place. A software program for analyzing 3D data was used to measure these 5 distances, and a data analysis software program was used for statistical and measurements analysis (α=.05). Results Significant differences ( P Conclusions Complete-arch digital scans of edentulous jaws are more accurate when an AGD is used to resolve the lack of anatomic landmarks. An additional advantage is that the use of the AGD allows for a more fluent scanning process.