Effect of print parameters on the accuracy and fit of 3D-printed resin-based ceramic crowns

This study evaluated the influence of print angle and layer thickness on the accuracy and fit of resin-based ceramic crowns fabricated using digital light processing (DLP). A mandibular first molar crown was virtually designed and then printed at two layer thicknesses (50 μm and 100 μm) and nine print angles (90°–270°). Accuracy was assessed by trueness, precision, and surface-resolved deviation metrics using 3D deviation analysis, whereas fit was evaluated with the triple-scan method. Both print angle and layer thickness significantly affected accuracy and fit ( P < 0.001). Trueness and fit values showed a nonlinear trend across print angles, with optimal results consistently observed at moderate inclinations of 150°–180°. Crowns printed at 50 μm showed better trueness and fit, whereas those printed at 100 μm showed more concentrated deviation distributions. Surface-resolved metrics revealed negative deviations at the marginal surfaces and positive deviations at the occlusal surfaces. Although all crowns showed clinically acceptable fit (<120 μm), the results indicate that a moderate print angle of 150°–180° combined with a 50 μm layer thickness provides the best balance between accuracy and clinical fit, while a 100 μm layer thickness may be preferable when printing consistency is prioritized.