Objectives: To study the outcome of different surface treatments on X ray diffraction analysis (XRD) and flexural strength of super translucent zirconia.
Materials and Methods: Forty identical discs were milled from presintered super translucent zirconia blank (VITA YZ ST, VITA Zahnfabrik, Germany). Specimens were classified into 4 groups according to the surface treatment used: Group C: no treatment (control group), Group S: discs were airborne particle, Group P: discs were treated with primer and Group SP: discs were airborne particle then, they were treated with primer. All specimens were subjected to XRD analysis and biaxial flexural strength test.
Results: The highest biaxial flexural strength recorded value was for the C group (462.11±17.33 MPa) while the lowest one was recorded for S group (310.33±7.78 MPa). Applying one way ANOVA and Tukey test revealed a statistically significant difference among all tested groups. The XRD analysis of specimens that were treated with different surface treatments revealed the evolution of monoclinic phase transformation in groups S and SP.
Conclusions: The airborne particle abrasion resulted in the evolution of tetragonal to monoclinic phase transformation on the zirconia surface which in turn negatively affected the flexural strength of super translucent zirconia.