Evaluation and Comparison of the Marginal Fit of Porcelain - Fused - to Metal Crowns before and after Porcelain Glazing Fabricated using Two Different Techniques

Purpose: To evaluate and compare the marginal fit of porcelain - fused - to metal crowns before and after porcelain glazing fabricated using conventional lost wax technique and Direct Metal Laser Sintering (DMLS) technique. Materials & methods: A total of 44 samples were prepared.22 samples were prepared using conventional lost wax technique and 22 samples using Direct Metal Laser Sintering (DMLS). These samples were sub - divided into 11 samples each of chamfer and deep chamfer finish lines in each group. Marginal fit was tested using Scanning Electron Microscope (SEM) for all the samples before and after glazing. Statistical analysis of the data was done using descriptive statistics to assess the mean and standard deviation of the respective groups, level of significance set at Pless than0.05. Results: A statistically significant difference (Pless than0.05) was observed between the values of all the groups for marginal fit. DMLS fabricated samples showed the least mean marginal fit (62.63?26.51?m & 87.32?27.87?m) before and after porcelain glazing compared to conventionally (90.97?31.35?m & 118.35?30.07?m) fabricated samples. Conclusion: DMLS fabricated samples showed the best marginal fit values compared to conventionally fabricated samples. The study concluded that DMLS technique had an edge over the conventional lost wax technique.