Patrick, DavidAlwasel, Abdullah2026-01-142025https://hdl.handle.net/20.500.14154/77871Aim: This study aimed to compare the marginal fit accuracy of gold crowns fabricated using three techniques: conventional lost-wax casting, CAD/CAM milling, and 3D-printed wax patterns. Materials and Methods: A standardised maxillary molar die with a chamfer margin was used to produce 33 wax copings (11 per group). Following inspection for defects, the best 10 copings from each group were cast in high-gold-content alloy. Nine crowns per group were selected for final analysis. Marginal gaps were measured at eight reference points per crown using two methods: manual stereomicroscopy and digital Crown Fit software. Statistical analysis included descriptive statistics, one-way ANOVA, and post hoc Tukey’s HSD tests with a significance level of p ≤ 0.05. Results: Manual stereomicroscope measurements showed mean marginal gaps of 12.22 µm (milling), 77.23 µm (3D printing), and 195.15 µm (conventional). Digital software measurements recorded higher values overall: 61.68 µm (milling), 66.75 µm (3D printing), and 252.99 µm (conventional). Both methods revealed statistically significant differences among the groups (p < 0.001). While milling consistently achieved the smallest gaps with the lowest variability, 3D printing demonstrated clinically acceptable though less consistent results. The conventional method produced the largest gaps and highest variability. Conclusion: Milling provided the highest accuracy and consistency under controlled in vitro conditions, although the extremely low values may reflect laboratory idealisation rather than true clinical performance. 3D printing achieved clinically acceptable fits but was more variable, underscoring the importance of optimised protocols. The conventional method, despite larger discrepancies, remains clinically serviceable, as supported by long-term evidence. Overall, both digital techniques offer promising alternatives, but further validation under intraoral conditions is recommended.61enconventional lost-wax castingCAD/CAM milling3D-printed wax patternsThesis