Pre-sintered Y-TZP sandblasting: effect on surface roughness, phase transformation, and Y-TZP/veneer bond strength

Abstract

Sandblasting is a common method to try to improve the Y-TZP/veneer bond strength of dental prostheses, however, it may put stress on zirconia surfaces and could accelerate the t→m phase transformation. Y-TZP sandblasting before sintering could be an alternative to improve surface roughness and bonding strength of veneering ceramic.Objectives.The aim of this study was to analyze the effect of Y-TZP pre-sintering sandblasting on surface roughness, phase transformation, and the Y-TZP/veneer shear bond strength.Material and Methods.The Y-TZP specimen surface underwent sandblasting with aluminum oxide (50 μm) pre-sintering (Z-PRE) and post-sintering (Z-POS). Z-CTR was not subjected to surface treatment. After ceramic veneer application, the specimens were subjected to shear bond testing. Surface roughness was analyzed by confocal microscopy. Y-TZP monoclinic and tetragonal phases were evaluated by micro-Raman spectroscopy. Shear bond strength and surface roughness data were analyzed by One-way ANOVA and Tukey tests (α=0.05). Differences in the wave numbers and the broadening bands of the Raman spectra were compared among groups.Results.Z-POS (9.73±5.36 MPa) and Z-PRE (7.94±2.52 MPa) showed the highest bond strength, significantly higher than that of Z-CTR (5.54±2.14 MPa). The Ra of Z-PRE (1.59±0.23 µm) was much greater and significantly different from that of Z-CTR (0.29±0.05 µm) and Z-POS (0.77±0.13 µm). All groups showed bands typical of the tetragonal (T) and monoclinic (M) phases. Y-TZP sandblasting before sintering resulted in rougher surfaces but did not increase the shear bond strength compared to post-sintering and increased surface defects.Conclusions.Surface treatment with Al3O2, regardless of the moment and application, improves the results of Y-TZP/veneer bonding and is not a specific cause of t→m transformation.

Effects of Liner-Bonding of Implant-Supported Glass–Ceramic Crown to Zirconia Abutment on Bond Strength and Fracture Resistance

“…The zirconia ceramics are usually roughened using an air-borne particle abrasion technology [34,35]. This procedure exposes sharp asperities of surface structures and increases surface area for bonding [36,37]. The resin cement should wet the surface and adhere to the irregular surface of ceramic restoration.…”

The effect of the repeated firings on the biaxial flexural strength of zirconia

“…24,25 Literatürde, zirkonya seramiklere uygulanan ısıl işlemlerin materyalin yapısında herhangi bir değişikliğe sebep olmadığını belirten çalışmalar mevcuttur. 26,27 Çalışmamızda ise materyal yapısındaki itriyum elementinin, tekrarlanan fırınlamalar sonucunda oransal olarak anlamlı ölçüde değiştiği tespit edilmiştir. Kontrol grubunla kıyaslandığında 1, 3 ve 5. fırınlamalar sonucunda materyalin yapısındaki itriyum oranı artmışken, zirkonyum elementinin oransal değişikliklerinin ise anlamlı olmadığı görülmüştür.…”

“…Öte yandan literatür incelendiğinde tekrarlanan fırınlamalar ve yüzeye uygulanan ısıl işlemlerin zirkonya üzerine etkilerinin inceleyen çalışmalarda örneklere final sinterleme sonrası yüzey işlemlerinin (kumlama, aşındırma, yaşlandırma) uygulandığı görülmektedir. 6,7,13,18,26,27,29 Marit ve arkadaşları 28 yapmış oldukları çalışmada 1. fırınlamadan sonraki tekrarlayan fırınlama prosedürlerinin materyalin özellikleri üzerine anlamlı bir etkisinin olmadığını ve 1. fırınlama ile diğer fırınlamalar arasındaki farkın ise örneklere sinterleme işlemi sonrası uygulanan farklı mekanik işlemlerin sonucu olarak meydana geldiğini belirtmişlerdir. Çalışmamızda tekrarlanan…”

Retentive Force of Glass-Ceramic Soldered Customized Zirconia Abutment Copings with Prefabricated Titanium Bases

“…Unlike the metal-silicate ceramic bond, the chemical bond between the zirconia structure and the veneer is not based on adhesive oxides but is rather dependent on hydrogen bridge bonds. This bond is described as good, but the adhesion values do not reach the same dimensions as those of the classic metal-silicate ceramic bond [ 16 , 17 , 18 , 19 ].…”