Sol–gel dip coating of yttria-stabilized tetragonal zirconia dental ceramic by aluminosilicate nanocomposite as a novel technique to improve the bonding of veneering porcelain

Abstract

The aim of this in vitro study was to evaluate the effect of silica and aluminosilicate nanocomposite coating of zirconia-based dental ceramic by a sol–gel dip-coating technique on the bond strength of veneering porcelain to the yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) in vitro. Thirty Y-TZP blocks (10 mm ×10 mm ×3 mm) were prepared and were assigned to four experimental groups (n=10/group): C, without any further surface treatment as the control group; S, sandblasted using 110 μm alumina powder; Si, silica sol dip coating + calcination; and Si/Al, aluminosilicate sol dip coating + calcination. After preparing Y-TZP samples, a 3 mm thick layer of the recommended porcelain was fired on the coated Y-TZP surface. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray analysis were used to characterize the coating and the nature of the bonding between the coating and zirconia. To examine the zirconia–porcelain bond strength, a microtensile bond strength (μTBS) approach was chosen. FT-IR study showed the formation of silica and aluminosilicate materials. XRD pattern showed the formation of new phases consisting of Si, Al, and Zr in coated samples. SEM showed the formation of a uniform coating on Y-TZP samples. Maximum μTBS values were obtained in aluminosilicate samples, which were significantly increased compared to control and sandblasted groups ( P =0.013 and P <0.001, respectively). This study showed that aluminosilicate sol–gel dip coating can be considered as a convenient, less expensive reliable method for improving the bond strength between dental Y-TZP ceramics and veneering porcelain.

Strengthen the bonding of self-glazed zirconia to enamel by sol–gel coating

“…Sol–gel process is a wet-chemical technique and has been widely used for coating. By depositing the sol onto the substrate, a thin film with different kinds of microstructures and properties could be obtained [40,41]. In the present study, after further application of sol–gel coating onto the intaglio surface of SZ, the bond strength was significantly improved, which was as high as that of LDe.…”

“…As opposed to APA, the sol–gel technique modifies the surface characters and improves the bond strength of SZ by forming a thin film with a special microstructure. This process is non-invasive and will not introduce severe defects if the process is well-controlled [41]. The mechanical property of the sol–gel coated SZ restorations would not be compromised, which also needs to be further studied.…”

Effect of different interfacial surface treatments on the shear bond strength of veneering ceramic and zirconia core

“…Group I showed SBS even lower than those of groups II and III, yet it is worth noting that there was no significant difference between the SBS values of these 3 groups. In a previous study by Bagheri et al, novel phases such Al 2 SiO 5 and zirconium aluminium oxide were produced using the sol-gel dipping coating approach using a silica and aluminosilicate sol-gel [ 32 ]. This suggests a chemical link between the veneering materials and the Y-TZP substrates, which strengthens the binding.…”