Objective: This study was conducted to examine the effect of various post-sintering interventions on the surface characteristics and hardness of translucent zirconia.
Materials and methods:
Thirty-eight zirconia discs were cut from InCoris-TZI blocks. Discs were sintered, cleaned, and divided into four groups according to post-sintering intervention (n=8 in each): Group P: Polished only, Group PG: Polished and Glazed, Group PHT: Polished and Heat treated for one glaze firing cycle, and Group PGHT: Polished, Glazed and Heat treated as the previous group. Each treatment was carried out according to the manufacturer's guidelines. One disc from each group was examined using a Scanning Electron microscope to explore the surface morphology. Surface roughness was assessed using an optical noncontact method. Micro-hardness of the specimens was evaluated using a Vickers diamond indenter. All data were calculated, and statistical analysis was performed.
Results: There was a significant difference between groups in surface roughness. The PHT samples had the greatest value (0.26±0.01) and the PG samples had the lowest one (0.23±0.03) while there was no significant difference between groups for microhardness.
Conclusions: Glazing following polishing Translucent zirconia exhibited the best surface smoothness. All post-sintering interventions had no effect on translucent zirconia surface hardness.