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Effect of different cooling regimens on the shear bond strength of veneering ceramic to zirconia

Thesis

Last updated: 05 Jan 2025

Subjects

-

Tags

Fixed Prosthodontics

Authors

Muhammad, Bushra Khaled

Accessioned

2018-08-26 05:26:07

Available

2018-08-26 05:26:07

type

M.Sc. Thesis

Abstract

Objective: aim of this study was to evaluate the effect of different veneering cooling regimens on the shear bond strength of veneering ceramic to zirconia and the mode of failure between them. Material and methods: 15 zirconia disc samples were constructed using CAD/CAM milling system. Samples were divided into 3 groups (n=5), according to the tested cooling regimen of the veneering porcelain:1- subjected to the recommended cooling regimen by the manufacture; 2- subjected to extra cooling time (six minutes) after both first and second dentine firing and after glaze firing; 3- subjected to extra cooling time (six minutes) after glaze firing only. Samples attached to specially designed stainless steel holding device which attached to the universal testing machine for measuring the shear bond strength. Results: there was no statistically significant difference between Group II and Group III; both showed the highest statistically significant mean shear bond strength (40.4 MPa, 33.8 MPa respectively). Group I showed the lowest statistically significant mean shear bond strength (22.3 MPa). By scanning electron microscope all groups showed mixed failure patterns. Conclusions: Both studied cooling protocols showed significant increase in the mean of shear bond strength values compared to the manufacture recommended cooling rate. Modifing the cooling time by using an additional, six-min long, cooling phase at the end of glaze firing only, was enough to improve the bond and saving the laboratory time.

Issued

1 Jan 2013

DOI

http://dx.doi.org/10.21473/iknito-space/39510

Details

Type

Thesis

Created At

05 Feb 2023