Reliability of the segmental intraoral scan strategy for the full-arch digitization

Background:The accuracy of intraoral scan is vital for dental prostheses, as scanning strategy significantly affects image quality, especially in full arch scans.This study aimed to assess the accuracy of full-arch intraoral scans using segmental scan methods.Methods: The study used three scan strategies for full-arch scans by varying the number of scan segments (1, 2, or 3) with straight or zigzag motions, using a dentate maxillary model mounted on a phantom head to simulate clinical conditions.The model was scanned using a structured light scanner and three different strategies, with each strategy repeated seven times, incorporating washout periods to minimize carryover effects.The 3D geometric accuracy of intraoral scans was evaluated using intermolar distance and global surface deviation, compared to a reference image.The Kruskal-Wallis test and Mann-Whitney U test were used to compare the deviations between the different scan pathway groups ( = 0.05).Results: Linear discrepancies in intermolar distance were similar for single and two-segment scans but higher for three-segment scans.Meanwhile, general values for global surface deviation did not differ significantly across all scan strategies. Conclusion:The two-segment scan method showed accuracy comparable to the single scan, suggesting it could be an alternative for full arch scans, though accuracy may decline with multiple segments.