Effect of Sandblasting Angle and Distance on Biaxial Flexural Strength of Zirconia-based Ceramics

Abstract

Aim: Surface treatment is necessarily required for bonding of zirconia to the veneering porcelain and luting cements. Sandblasting is the most common and probably the most efficient surface treatment method. Sandblasting roughens the surface and may affect the flexural strength of zirconia. Different sandblasting protocols may yield variable results. This study sought to assess the effect of sandblasting angle and distance on the biaxial flexural strength of zirconia-based ceramics. Materials and methods:This in vitro experimental study was conducted on 50 zirconia discs measuring 1.2 ± 0.2 mm in thickness and 15 ± 0.2 mm in diameter, which were randomly divided into five groups (n = 10) of one control and four experimental groups subjected to sandblasting with 110 µm aluminum oxide particles under 2 bar pressure for 10 seconds at 15 and 25 mm distances and 45 and 90° angles (between the nozzle head and zirconia surface). Surface roughness was measured by a roughness tester and samples were subjected to thermocycling followed by biaxial flexural strength testing according to ISO6872. The data were analyzed using one-way analysis of variance (p < 0.05).Results: No statistically significant difference was noted in the mean biaxial flexural strength of the five groups (p = 0.40). Different sandblasting protocols yielded significantly different surface roughness values (p < 0.001). The highest and the lowest mean surface roughness belonged to 15 mm/90° (0.51 µm) and control (0.001 µm) groups respectively. Conclusion:Change in sandblasting angle and distance had no significant effect on the biaxial flexural strength of zirconiabased ceramic, but surface roughness was significantly different in the study groups. Effect of Sandblasting

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

“…In addition, the sandblasting can be effective to increase the surface area, surface wettability, and therefore the surface energy [11]. However, the bonding performance would be highly dependent on the sandblasting conditions, such as the size and shape of abrasive particles [12,13], air pressure [12,14], working duration [15], distance [14,16], and impact angle [16]. The sandblasting tends to trigger the tetragonal to monoclinic phase transformation of conventional high-strength zirconia (3Y-TZP) [17], whereby the transformation toughening mechanism [2] can lead to increased mechanical strengths [14].…”

“…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.…”

Topographical and crystalline change on surface by sandblasting improve flexural and shear bond strength of niobia-modified yttria-stabilized tetragonal zirconia polycrystal

“…In this experiment, both chemical treatment with MDP and mechanical treatment via alumina sandblasting were used. Mechanical treatment via sandblasting is affected by various parameters, such as particle size 27) , air pressure 27) , sample-nozzle distance 28) , working time 19) , and impact angle 28) , and the optimal protocol for treatment of translucent zirconia is still unclear. Previous studies have reported different optimal particle sizes and pressures for achieving reliable bond strength, with some suggesting that 50 µm and 0.2 MPa are the most effective 29,30) , whereas others have found that larger particles or higher pressures can increase bond strength 31,32) .…”

Experimental Silane Primer and Grit-Blasting Distance in Orthodontic Bonding of Zirconia Surfaces

“…Grit-blasting at a close distance is found to initiate heat, chipping, and cracking of the zirconia surface, thereby generating residual stresses through which strength reducing flaws are introduced [27]. On the contrary, increased distance is associated with lower surface roughness resulting in decreased or unacceptable zirconia adhesion strength [26,27].…”