Diffusion and Thermal Shock Behaviour of Silicate Dental Ceramics

The purpose of this study is to examine the diffusion and thermal shock behaviour of the alternative dental silicates. The samples derived from BaO-SiO2 system have been produced by melting process and followed by the heat treatment. X-ray examinations have indicated that the amount of orthorhombic sanbornite phase rised due to treatment temperature as revealed by the peak intensities. The alteration of the morphology by treatment temperature was evident from scanning electron microscopy SEM images. Crystallization at low temperature produced small crystallites and coarsening was not observed with a rise in temperature. The failure of the dental samples after the thermal shock test was examined using SEM. A continuous crack geometry and very few crack branching were observed. Diffusivity constant (D) and diffusion rate were examined vs treatment temperature for the present system. Diffusion depth (L) was doubled when the crystallization treatment was applied. Based on the obtained results, these silicate samples might take part in the further characterization studies to be used as alternative dentistry materials.