The coefficient of thermal expansion of core and veneer porcelains for all ceramic crowns must be compatible to prevent formation of stresses during the firing cycles. The purpose of this study was to use a thermal shock test to evaluate the crazing resistance of six all-ceramic crown systems. The systems tested were: Vita In-Ceram, Vita Hi-Ceram, Dicor veneered with Vitadur N, magnesia core ve...

Mesoporous Ni–alumina catalysts (Ni–alumina-pre and Ni–alumina-post) were synthesized by one-step sol–gel method using micelle complex comprising lauric acid and nickel ion as a template with metal source and using aluminum sec-butoxide as an aluminum source. The Ni–alumina catalysts showed relatively high surface areas (303 m/g for Ni–alumina-pre and 331 m/g for Ni–alumina-post) and narrow por...

Objective: In this study, the effects of ceramic, chromium-nickel (Cr-Ni) and ceramic opaque sinterized on chromium-nickel (Cr-Ni+opaque) post-core materials and different colored (opaque white, white, yellow and brown) cements on final color of all-ceramics materials (In-Ceram, IPS Empress and IPS Empress II) were investigated. Material and Methods: Three groups of post-cores (ceramic, Cr-Ni a...

The aim of this study was to compare the in vitro caries inhibition of various resin-based materials. Class V cavities were prepared in twenty-five freshly extracted human premolar teeth which were then restored with glass-ionomer cement (Chemfill II), compomer (Compoglass F, Dyract AP) and composite resin (Tetric Ceram and Z 100). The teeth were submerged in an acid gel for 6 weeks. Each speci...

a simple method for fabrication of highly ordered gold nanorod film is introduced in this article. the procedure is based on thermal evaporation of gold into a porous anodic alumina film (paa). the ppa film was fabricated by combining the hard and mild anodization. this combination effectively decreases the processing time of fabrication of highly ordered porous anodic alumina film with control...

Aluminum/alumina composites are used in automotive and aerospace industries due to their low density and good mechanical strength. In this research, the effect of mechanical stirring of slurry in liquid-solid phase temperature and injection of alumina powder with inert gas (Ar) on microstructure and mechanical properties of Al-A356 alloy is investigated. In order to improve of the wettability a...

INTRODUCTION This study evaluated the cervical fit of cemented metal-ceramic and In-Ceram implant-supported crowns, before and after the cementing procedure. MATERIALS AND METHODS Twenty crowns cemented on implant abutments are divided into two groups (n = 10): Group 1 -cemented metal-ceramic crowns and group 2 - cemented In-Ceram crowns. The marginal adaptations before and after cementation ...

. AbstrAct Objective. In clinical practice, core material can be exposed after adjustments, which may result in loss of ceramic glaze. The objective of this study is to evaluate the effect of surface roughness on the flexural strength and fracture toughness of In-Ceram zirconia core material. Materials and methods. Forty In-Ceram zirconia specimens were prepared and divided into two main groups...