Critical methodological factors influencing the accuracy of intraoral scanners in digital dentistry research

This in vitro study aimed to identify the key methodological factors influencing the accuracy of intraoral scanners (IOS). The primary factors analyzed included the length of the scanned area, the total number of alignment points, the software used for analysis, and the operator's expertise. Three IOS systems were assessed-CEREC Primescan, Trios 3, and Omnicam-along with a laboratory desktop scanner (inEos X5). Scans were performed on a mandibular typodont, with the Root Mean Square (RMS) error used to measure the discrepancies between reference and experimental scans. The results indicated that the length of the scanned area significantly affected the RMS values, with full-arch scans producing greater errors compared to those of quadrant scans. Additionally, the total number of alignment points in the standard tessellation language files positively influenced accuracy, although improvements plateaued beyond 20 points. The choice of processing software also impacted accuracy, with Geomagic Control X yielding significantly lower RMS values than those of MeshLab and CloudCompare. Finally, user expertise played a significant role in scanning accuracy, with the experience user achieving more precise results, especially when using the Trios 3 scanner. Thus, the length of the scan, number of alignment points, software tools, and operator expertise significantly influence the accuracy of IOS, highlighting the importance of considering these methodological factors in both clinical and research settings for digital impressions.