Effect of Two Brands of Glaze Material on the Flexural Strength and Probability of Failure of High Translucent Monolithic Zirconia

Abstract

(1) Background: The effect of glazing on the mechanical properties of monolithic high translucent zirconia is not well reported. Therefore, the purpose of this study was to evaluate the effect of glazing on the flexural strength of high translucent zirconia; (2) Methods: Ninety specimens were prepared from second-generation 3Y-TZP high translucent blocks and divided into three groups. Glaze materials were applied on one surface of the specimen and subjected to a four-point bending test and flexural stress and flexural displacement values were derived. Descriptive fractographic analysis of surfaces was conducted to observe the point of failure and fracture pattern.; (3) Results: Control-nonglazed (647.17, 1σ = 74.71 MPa) presented higher flexural strength values compared to glaze I (541.20, 1σ = 82.91 MPa) and glaze II (581.10, 1σ = 59.41 MPa). Characteristic strength (σƟ) from Weibull analysis also observed higher (660.67 MPa) values for the control specimens. Confocal microscopy revealed that glazed surfaces were much rougher than control surfaces. Descriptive fractographic analysis revealed that there was no correlation between the point of failure initiation and flexural strength; (4) Conclusions: The test results demonstrated that glazing significantly decreased the flexural strength and flexural displacement of the zirconia specimens.

Comparative effects of glazing versus polishing on mechanical, optical, and surface properties of zirconia ceramics with different translucencies

“…Cubic zirconia with higher yttria content has lower transformation toughening, resulting in a significantly lower flexural strength (Zhang et al, 2016 ). The flexural strength results of the present study were in agreement with those of Singh et al ( 2021 ) and Kumchai et al ( 2018 ). They showed that glazing of high‐translucent zirconia significantly decreased the flexural strength at the corner of several specimens.…”

“…Ozturk et al ( 2022 ) and some others (Fairhurst et al, 1992 ; Yener et al, 2011 ) showed that glazing decreased the flexural strength, which may be due to the formation of monoclinic phase with poor mechanical properties at high glazing temperatures, and also reverse transformation. The same result was obtained in glazed subgroups of the present study (Singh et al, 2021 ). Some researchers (Denry & Kelly, 2008 ; Sundh et al, 2005 ) showed that heating of Y‐TZP at 900°C for 1 h or 900–1000°C for 1 min would cause reverse transformation and reduction in flexural strength, due to reverse transformation.…”

Evaluation of the Effect of Different Glazing Brands on Hardness of Monolithic Zirconia Fabricated By CAD/CAM Technique

“…In Table [5], Post Hoc Test (Bonferroni) shows a statistically significant difference between each two of the studied groups (VITA, Ivoclar, GC and Soprano) for hardness with p-value < 0.05, except for two, there no statistically significant association between (VITA & soprano) glaze and between (Ivoclar & GC) glaze with p-value > 0.05 for both. In Table [6], Energy-Dispersive X-Ray Analysis show the effect of the glazing materials on hardness will be related to one elemental composition Al weight % (7), which is used in this study. While the glazing material (powder) had more Aluminum (Al) in GC group than Ivoclar, VITA and Soprano.…”

“…The aim is to seal the open pores on the surface of sintered porcelain and to produce a smooth glossy layer. Despite there being several reports that glazing monolithic zirconia wears off the surfaces in contact with antagonists, the practice of staining and glazing monolithic restorations are commonly employed to achieve an improved and acceptable aesthetics that is superior to that of the monolithic intrinsic color of the crown (6). Glazed surfaces on ceramic surfaces have the potential to reinforce them.…”

Surface Characterization of Current Dental Ceramics Using Scanning Electron Microscopic and Atomic Force Microscopic Techniques

“…After glazing, the restorations appear shiny and esthetic. The finished restorations are cemented in the patient's mouth using adhesive cement [16][17][18][19].…”