objectives: dental composite wear in posterior restorations is a concern and is affected by different factors. this study was conducted to evaluate the effect of polishing and mechanical loads on wear of silorane-based and methyl methacrylate-based composites resins. materials and methods: of each dental composite (filtek p90 and filtek p60), 40 samples were fabricated in a polyethylene mold (4...

Not only can teeth provide clues about diet, but they also can be indicators of habitat quality. Conspecific groups living in different habitats with different kinds of foods may exhibit different rates of dental attrition because their teeth are less well adapted to some foods than to others. Ecological disequilibrium describes the situation in which animals live in habitats to which they are ...

plasma electrolytic oxidation (peo) was performed on a 1010 aluminum alloy. to achieve thenanocomposite structure, si3n4 nanoparticles were added into the electrolyte. in an alkaline aqueoussuspension (silicate-based), the effect of adding niso4 on the applied voltage, microstructure,composition, wear, and corrosion resistance of peo coatings was investigated using scanningelectron microscopy (...

In this study, the effect of deposition regime on the wear behavior of VK8 coating applied to 1.2344 tool steel by electro spark method (ESA) was investigated. After sample preparation, the coating with high and low regime was applied. To assess the wear behavior, the pin on disk test method according to ASTM G99-04, was used. For surveying surface morphology and cross section of the coating as...

The effect of squeeze casting process parameters on wear behavior of AC2A aluminium alloy was primarily investigated in this experimental study. Five process parameters, namely squeeze pressure, pouring temperature, die temperature, die material and compression time, each at four levels were chosen and sixteen experimental runs based on L16 orthogonal array were performed. From analysis of vari...

In the present study, Al5083- Al2O3 nanocomposite was successfully prepared by friction stir processing (FSP) with rotational speed of 710 rpm and travel speed of 14 mm/min. In order to improve distribution of Al2O3 particles, a net of holes were designed on the surface of Al5083 sheet. The samples were characterized by optical and scanning electron microscopy (SEM), microhardness, tensile and ...

AIMS The corneal epithelial permeability during extended wear of disposable contact lenses was compared with that during daily wear of soft contact lenses. The study was performed to verify whether the extended wear of disposable contact lenses would result in a higher permeability value than the daily wear of soft contact lenses. A higher permeability makes the cornea more vulnerable for bacte...

The wear of cental amalgam was studied by single- and double-pass sliding and by a silicon carbide abrasion test. A dispersed amalgam showed significantly better resistance to two-body abrasion than the spherical amalgams tested. The wear amalgam was determined by resistance to penetration and by a ductile mode of surface failure over the load range studied. Differences in the wear of amalgam a...