الفهرس 
Composition of dental porcelain materialOnly 14 pages are availabe for public view
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Abstract
Keyword: zirconia restorations repair, nanohybrid composite, two different adhesives, shear bond strength, water storage and thermocycling aging.Objectives: the purpose of this in-vitro study was to study and evaluate shear bond strength of fractured zirconia repaired by nanohybrid composite immediately and after 180 days of water storage and thermocycling aging using two different adhesives.Methods: A total of forty zirconia disc samples (10 mm in diameter, 2 mm in thickness) were prepared by a CAD/CAM system (SILADENT) using prefabricated blocks of zirconia (KZR-CAD NANOZR, Japan) and then each zirconia samples were embedded in epoxy resin. Mechanical surface pretreatment was stimulated by surface roughening of zirconia samples using a special zirconia grinding burs (VOCO GmbH, Germany, Cuxhaven) at low pressure and without water cooling.Forty samples were equally divided into two groups. In the first group, 20 samples were treated with Futurabond M+ adhesive. In the second group, 20 samples were treated with Panavia F 2.0 adhesive, and each sample was cured with light curing unit according to manufacture instructions. After the application of the adhesives, Grandio nanohybrid composite resin was applied into two increments over the treated surface of samples using a plastic tube (4mm in diameter and 3mm in height), Each group will be further divided into two subgroups for shear bond strength testing immediately and after water storage and thermocycling aging, shear bond strength was tested for all specimens, using universal testing machine.