Effect of additional firing process after sintering of monolithic zirconia crown on marginal and internal fitness / 대한치과보철학회지

ABSTRACT

PURPOSE: To evaluate an effect of additional firing process after sintering of monolithic zirconia crown on marginal and internal fit through three-dimensional analysis. MATERIALS AND METHODS: Ten monolithic zirconia crowns were fabricated using titanium abutment model. Monolithic zirconia crowns were designed, milled, and sintered as a control group, and additional firing with coloring was performed as a test group. Three dimensional analysis were performed by using triple-scan protocol, and cross-section analysis on mesio-distal and disto-lingual section was evaluated to measure marginal and internal fitness. Then, three-dimensional surface difference on between two groups was evaluated (α=.05). RESULTS: There was statistically significant difference between the control group (32.0 ± 24.3 µm) and the test group (17.0 ± 10.8 µm) in the mesial axial wall (P < .02) and the control group (60.2 ± 24.3 µm) and the test group (71.8 ± 21.5 µm) in the distal axial wall (P < .01). There was no statistically significant difference at the remaining point. CONCLUSION: There was no statistical significance on the deviation of inner surface of crown according to firing number, and the results of both group were considered clinically acceptable.