Effect of MgO on physical and mechanical properties of dental porcelain

The aim of this work is to investigate the effect of MgO on physical and mechanical properties of Dental Porcelain. MgO was used in this work as particle reinforcement to improve these properties. 0.5, 1.0 and 1.5 weight percentages of MgO were reinforced in Dental Porcelain (75 wt% feldspar, 20 wt% quartz and 5 wt% kaolin). The samples were made by powder pressing process and sintered in one step sintering technique and sintered at three different temperatures (1050 degrees C, 1100 degrees C and 1150 degrees C). The prepared samples were tested by using X-Ray Fluorescence (XRF), Scanning Electron Microscope (SEM) and Differential Scanning Calorimeter (DSC), Universal Testing Machine (UTM) X-Ray Diffraction (XRD) and Vickers Hardness Tester to characterize the chemical composition, microstructure and phases present, fracture toughness, hardness respectively. Physical and mechanical properties such as density, hardness, diametral tensile strength, flexural strength and fracture toughness were determined. The addition of MgO up to 1% in 1100 degrees C influences all the physical and mechanical properties which was positive, where further addition of MgO showed adverse effect.