OBJECTIVE: Evaluation of the accuracy of direct digitization of maxillary scans depending on the scanning strategy. MATERIALS AND METHODS: A maxillary model with a metal bar as a reference structure fixed between the second molars was digitized using the CEREC Primescan AC scanner (N = 225 scans). Nine scanning strategies were selected (n = 25 scans per strategy), differing in scan area segmentation (F = full jaw, H = half jaw, S = sextant) and scan movement pattern (L = linear, Z = zig-zag, C = combined). Trueness was assessed by evaluating linear differences in the X, Y, and Z axes and angular deviations (α axial, α coronal, α total) compared to a reference dataset. Statistical differences were analyzed using Kruskal-Wallis and Mann-Whitney U tests (p<
0.017). Precision was analyzed by the standard deviation of linear and angular aberrations (ISO 5725-1) (p <
0.05). RESULTS: Strategy F CONCLUSIONS: Scanning motion and segmentation have a significant impact on the trueness and precision of full-arch scans. CLINICAL RELEVANCE: The scanning strategy is decisive in enhancing the clinical workflow and the accuracy of full-arch scans.