Effects of Different Sintering Times on The Adaptation of Monolithic Zirconia Crowns

Changes to heat and time during the sintering process, which is one of the most critical stages in the production of monolithic zirconia crown restoration, can affect the physical properties of the material. The study was examined the effect of change in sintering time on the adaptation of monolithic zirconia crowns. Sixty monolithic crowns in upper first molar tooth form were produced from Y-TZP semi-sintered different blocks. Samples were divided into three groups according to brands and two subgroups according to sintering time (n=10). Marginal and internal gaps were photographed with a video microscope at x 180 magnification. The two-way ANOVA test was used for the effect of brand, and sintering time on adaptations were examined. There was no statistically significant difference in the overall gap values between the groups according to the long sintering times (p> 0.05). In crowns produced from zirCAD and Lava blocks, marginal gap values were not affected statistically significantly from sintering time (p>0.05). In crowns produced from katana blocks, shortening of sintering time caused a statistically significant increase in marginal and occlusal gap values (p<0.05). It can be said that the sintering time and temperature are an important factor in the biocompatibility of monolithic crowns.