Effects of Surface Treatments on Mechanics Behavior of Sintered and Pre-sintered Yttria-Stabilized Zirconia and Reliability of Crowns and Abutments Processed by CAD/CAM
التفاصيل البيبلوغرافية
العنوان:
Effects of Surface Treatments on Mechanics Behavior of Sintered and Pre-sintered Yttria-Stabilized Zirconia and Reliability of Crowns and Abutments Processed by CAD/CAM
Purpose: This study evaluated the micro shear bond strength of resin cement to an yttria-stabilized zirconia ceramic and the survival probability of zirconia abutments and crowns after different surface treatments through a fatigue test. Materials and Methods: The study was divided into two parts. For part 1, 95 zirconia disks were divided into five groups (n = 19): control, untreated, airborne particle abrasion with Al2O3 particles before sintering, airborne particle abrasion with Al2O3 particles after sintering, silicatization before sintering, and silicatization after sintering. Three samples of each group were used for evaluation of surface roughness by confocal laser scanning microscopy and afterward were prepared for surface microstructural analysis by scanning electron microscopy. Ten samples of each group were subjected to micro shear bond strength testing, and the interfaces of the remaining six were examined by scanning electron microscopy. In part 2, 70 external hex zirconia abutments and copings were made by computer-aided design/computeraided manufacturing (n = 14). Marginal fit of abutment/coping was measured in a confocal laser scanning microscope. Afterward, a fatigue test was carried out with progressive load of 80 up to 320 N (40 N steps), 5 Hz frequency, and 20,000 cycles at each step. Thermal cycling was simultaneously performed (5 degrees C to 55 degrees C). Results: The group treated after sintering with SiO achieved statistically higher micro shear bond strength (P
