Investigation of the Accuracy of Four Intraoral Scanners in Mandibular Full-Arch Digital Implant Impression: A Comparative In Vitro Study

Background: We compare the accuracy of new intraoral scanners (IOSs) in full-arch digital implant impressions. Methods: A master model with six scan bodies was milled in poly(methyl methacrylate), measured by using a coordinate measuring machine, and scanned 15 times with four IOSs: PrimeScan, Medit i500, Vatech EZ scan, and iTero. The software was developed to identify the position points on each scan body. The 3D position and distance analysis were performed. Results: The average and +/- standard deviation of the 3D position analysis was 29 mu m +/- 6 mu m for PrimeScan, 39 mu m +/- 6 mu m for iTero, 48 mu m +/- 18 mu m for Mediti500, and 118 mu m +/- 24 mu m for Vatech EZ scan (p < 0.05). Conclusions: All IOSs are able to make a digital complete implant impression in vitro according to the average misfit value reported in literature (150 mu m); however, the 3D distance analysis showed that only the Primescan and iTero presented negligible systematic error sources.