The tensile behavior of a Ni60Nb40 metallic glass (MG) has been studied by using ab initio density functional theory (DFT) calculation with a large cell containing 1024 atoms (614 Ni and 410 Nb). We provide insight into how a super elastic limit can be achieved in a MG. Spatially inhomogeneous responses of single atoms and also major polyhedra are found to change greatly with increasing externa...

OBJECTIVE This study was designed to evaluate the effect of two bleaching agents on the fluoride release of three types of glass ionomer materials. MATERIALS AND METHODS A total of 90 specimens of the tested materials (Ketac Fil, Photac Fil and F2000) were prepared by a split Teflon ring with an internal diameter of 5 mm and thickness of 2 mm. The tested materials were applied and bleached ac...

introduction: in restorative dentistry, selecting the proper material is an important factor for clinical success. the objective of this study was clinical evaluation of survival time of three tooth color materials in primary anterior teeth. methods: in this interventional clinical trial study, 94 deciduous anterior teeth (36 teeth in boys, 58 teeth in girls) belonging to 3-5 year old children ...

Immiscible blends of ethylene?propylene?diene?monomer (EPDM) and polyoxymethylene (POM), when EPDM is the major phase were compatibilized on addition an ionomer, poly(ethylene?co?methacrylic acid). The inclusion ionomer reduced interfacial tension between two phases, such that diameter POM domains significantly to 0.5 2 ?m, typical required toughen ductile polymers. mechanical properties result...

background: scuba diving is one of the fastest growing sports in the world. the objective of this study was to evaluate the effect of pressure variations to which divers are exposed on the pull out strength of glass fiber post luted with different cements. materials and methods: in this in vitro study, 120 extracted, single-rooted lower premolars were endodontically treated. they were randomly ...

The purpose of this study was to evaluate cuspal flexure in posterior primary teeth following restoration with three different materials. Twelve primary second molars were obtained. A precision strain gage was attached to the buccal surface of each tooth and balanced at zero. The teeth were mounted and then loaded with a 10 kg force; the strain appearing on the strain gage indicator was recorde...

BACKGROUND Pulpal reaction to restorative materials depends on marginal microleakage, which is a dynamic phenomenon that allows bacteria and fluids to traverse across the tooth-restoration interface. Glass-ionomer cement (GIC) exhibits low microleakage due to direct bonding to tooth structures. Hydroxyapatite (HAP) based on the similarity with tooth structure may decrease the microleakage. The ...

PURPOSE This in vitro study compared bond strength and fracture modes of tooth-colored restorations in 2 types of cavity preparations in human primary molars. METHODS Standardized Class II cavities (40 dovetail and 40 box-only preparations) in extracted human primary molars were restored with packable composite resin (PC), resin-modified glass ionomer cement (RMGIC), resin-modified glass iono...