Mounajjed, Radek

Abstract Purpose This study evaluated and compared the marginal fit of CAD–CAM zirconia crown copings with and without a 3D‐printed control model. Materials and Methods This prospective in vitro trial involved 30 zirconia crown copings made from the same STL file. These were divided into two groups. Half of them had their own 3D‐printed control model made from the same STL file (With‐Printed‐Model group), whereas the other half lacked any control model (No‐Printed‐Model group). Both groups underwent manual adjustments in a systematic way. Their marginal gaps were evaluated using a digital optical microscope from eight zones: buccal, mesiobuccal, mesial, mesiopalatal, palatal, distopalatal, distal, and distobuccal. Results The mean values with standard deviations for the With‐Printed‐Model and No‐Printed‐Model groups were 15.18 ± 14.49 and 12.46 ± 14.09 µm, respectively. All crown copings from both groups were below 75 µm. Statistical analysis showed a significant difference between the two groups. Conclusion The No‐Printed‐Model group demonstrated superior marginal fit compared to the With‐Printed‐Model group. However, the largest marginal gaps from each group were still within the clinically acceptable range below 75 µm. Although the 3D‐printed control model did not improve marginal fit, its primary function is to effectively identify major manufacturing errors.