Influence of alumina air-abrasion for highly translucent partially stabilized zirconia on flexural strength, surface properties, and bond strength of resin cement

Abstract

Influence of alumina air-abrasion for highly translucent partially stabilized zirconia on flexural strength, surface properties, and bond strength of resin cement Objective: This study aims to evaluate the influence of different airabrasion pressures and subsequent heat treatment on the flexural strength, surface roughness, and crystallographic phases of highly translucent partially stabilized zirconia (Y-PSZ), and on the tensile bond strength of resin cement to Y-PSZ. Methodology: Fully sintered zirconia specimens were ground with SiC paper (control) and/or air-abraded with 50 µm particles of alumina at 0.1, 0.15, 0.2, or 0.3 MPa or left as-sintered. After air-abrasion at 0.2 MPa (0.2AB), additional specimens were then heated to 1500°C, and held for one hour at this temperature (0.2AB+HT1h). Flexural strength and surface roughness were evaluated. Crystalline phase identification was also carried out using X-ray diffraction. Bonded zirconia specimens with self-adhesive resin cement were stored in distilled water at 37°C for 24 h, either with or without aging (thermal cycling 4-60°C/20000). Results were analyzed statistically by ANOVA and Tukey-Kramer tests. Results: The flexural strength decreased with the increase in air-abrasion pressure, while in contrast, the surface roughness increased. The lowest flexural strength and the highest roughness value were found for the 0.2AB and 0.3AB groups, respectively. All groups contained cubic-, tetragonal (t)-, and rhombohedral (r)-ZrO 2 phases with the exception of the as-sintered group. Upon increasing the air-abrasion pressure, the relative amount of the r-ZrO 2 phase increased, with a significant amount of r-ZrO2 phase being detected for the 0.2AB and 0.3AB groups. The 0.2AB+HT1h group exhibited a similar flexural strength and t-ZrO2 phase content as the as-sintered group. However, the 0.2AB group showed a significantly higher tensile bond strength (p<0.05) than the 0.2AB+HT1h group before and after aging. Conclusion: Micromechanical retention by alumina air-abrasion at 0.2 MPa, in combination with chemical bonding of a resin to highly translucent Y-PSZ using a MDP-containing resin cement may enable durable bonding.

Effect of Al2O3 Sandblasting Particle Size on the Surface Topography and Residual Compressive Stresses of Three Different Dental Zirconia Grades

“…However, these studies were conducted under different sandblasting parameters. A recent study reported that the flexural strength of sandblasted highly translucent zirconia decreased with increasing air-abrasion pressure [ 36 ]. In that study, only 50 μm alumina sand was employed and the flexural strength was measured using a three-point bending test with the loading on the blasted surface.…”

“…Appropriate sandblasting protocols on the durable bond between resin cement and highly translucent zirconia have not well been studied yet. Moreover, most of the previous studies on the various effects of alumina sandblasting have used only a few particle sizes; 50 μm [ 14 , 18 , 33 , 34 , 35 , 36 ], 50 and 110 μm [ 9 , 12 , 15 ], 110 μm [ 16 ], 150 μm [ 13 ], 110 and 250 μm [ 17 ]. This study focused on the influence of the sandblasting particles with five different sizes on the sandblasting performance of dental monolithic zirconia with three different levels of translucency, while other sandblasting parameters were kept constant.…”

Effect of Pressure and Particle Size During Aluminum Oxide Air Abrasion on the Flexural Strength of Disperse-Filled Composite and Polymer-Infiltrated Ceramic Network Materials

“…Some studies reported that surface treatment using air abrasion caused tetragonal–monoclinic transformation toughening and formation of a compressive layer on the surface of the zirconia material that improved its flexural strength [ 30 , 31 , 32 ]. Other studies have reported that the flexural strength decreased as flaws (e.g., cracks) formed on the surface [ 33 , 34 ]. The DFC material used in our study contains a zirconia filler, but its proportion is too small for the transformation toughening to affect the flexural strength.…”

Effect of air‐abrasion at pre‐ and/or post‐sintered stage and hydrothermal aging on surface roughness, phase transformation, and flexural strength of multilayered monolithic zirconia

“…By contrast, Chintapalli et al 52 declared that air‐abrasion using ≤110‐μm particles and lower than 4‐bar pressure increased the flexural strength and reliability of zirconia. Therefore, in the present study, zirconia specimens were air‐abraded using 50‐μm Al 2 O 3 particles under 3‐bar pressure, as applied in previous studies 25,53 …”

“…Therefore, in the present study, zirconia specimens were airabraded using 50-μm Al 2 O 3 particles under 3-bar pressure, as applied in previous studies. 25,53 It was considered that there might be mainly two opposing mechanisms determining the flexural strength of zirconia. Specifically, a surface compressive layer formed by t !…”