This study assessed the
fatigue performance (biaxial flexure
fatigue strength), surface characteristics (topography and roughness) and structural stability (t-m phase transformation) of a
Y-TZP ceramic subjected to air-abrasion using new powders (7% and 20%
silica-coated
aluminum oxide particles) in comparison to commercially available powders. Disc-shaped specimens were manufactured (ISO 6872-2015) and randomly allocated into four groups considering the air-abrasion materials: SiC: commercially available
silica-coated
aluminum oxide; AlOx: commercially available
aluminum oxide; 7%Si and 20%Si: experimentally produced materials consisting of 7% and 20%
silica-coated AlOx, respectively. Air-abrasion was executed by a blinded researcher (1 cm distance from the tip to the specimen surface, under 2.8 bar pressure for 10 s). The
fatigue tests (n = 15) were performed by the staircase method under a piston-on-three-balls assembly. Topography and roughness assessments (n = 30) of abraded samples and fractography of failed discs were performed. The highest
fatigue strength (MPa) was observed for 7%Si (887.20 ± 50.54) and SiC (878.16 ± 29.81), while the lowest
fatigue strength for 20%Si (773.89 ± 46.44) and AlOx (796.70 ± 46.48). Topography analysis depicted similar surface morphology for all conditions. However, roughness (μm) was only statistically different between 7%Si (Ra = 0.30 ± 0.09; Rz = 2.31 ± 0.63) and SiC (Ra = 0.26 ± 0.04; Rz = 1.99 ± 0.34). Monoclinic phase grains appeared on Y-TZP surface in a similar content (≈11-12%) for the protocols. Fractography showed all failures starting on air-abraded surface/sub-surface defects from the tensile side. In terms of roughness, phase transformation and
fatigue, the new 7%
silica-coated
aluminum oxide presented similar behavior to the commercially available
powder. Increasing
silica-coating concentration to 20% did not lead to a gentle air-abrasion protocol.