الفهرس 
Zirconia restorations
Effect of different surface treatments on zirconiaOnly 14 pages are availabe for public view
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Abstract
The purpose of this study was to evaluate the effect of air abrasion and
silica-coating of zirconia in pre-sintered and post-sintered stages on the
surface roughness, phase transformation, biaxial flexural strength (BFS), and
tensile bond strength (TBS) to resin cement.
Zirconia discs (Bruxzir, Glidewell, California, USA) were divided into
two groups according to the timing of surface treatment (pre-sintered and postsintered). Each group was divided into two subgroups according to the type of
surface treatment; air abrasion using 50 µm alumina particles (AB) and silicacoating using 30 µm silica-modified alumina particles (SC). A control group
with no surface treatment was also tested. Surface roughness was analyzed
using a 3D laser microscope and phase transformation was assessed using a
diffractometer. BFS was tested using piston-on-three ball technique in a
universal testing machine, and TBS to Panavia V5 with Clearfil Ceramic
Primer Plus (Kuraray, Osaka, Japan) resin cement was tested both after 3 days
of water storage and after 150 days of water storage combined with
thermocycling. Data was analyzed using multivariate analysis of variance and
Tukey’s post hoc test.
Results showed that surface roughness was higher in the group treated
in the pre-sintered stage than the one treated in the post sintered stage. The
pre-sintered treated group and the control showed no monoclinic phase while
the post-sintered group showed significantly higher portions of monoclinic
phase. Regarding BFS the post-sintered treated group had statistically
significant higher values when compared to the pre-sintered treated group and
the control. Highest TBS values were achieved with the post-sintered silicacoated subgroup. No significant differences were found between the postsintered air-abraded subgroup and the pre-sintered treated group. All subgroups showed higher TBS values when compared to the control group.
However, after thermocycling a dramatic decrease in TBS values was noticed
in the samples that were silica coated.