the aim of this study was to assess the effect of bleaching on elution of monomers from nanofilled and microhybrid composites.80 samples (5mm diameter and 3mm thickness) of each composite were prepared. after curing, half of them were randomly polished. each group was divided into 8 subgroups and immersed in water or 10%, 20% and 30% h2o2 for 3 or 8 hours. eluted bis-gma (bis-phenol a glycidyl ...

Background: One of the aesthetic issues in use composite resin is color change. The study aims to compare changes nanofiller before and after immersion red grape juice with different curing durations. Method: This involved 18 round resins a diameter 12 mm thickness 2 mm. sample was divided into three groups (n=6); group A cured for 20 seconds, B 30 C 40 seconds. After curing, samples were immer...

In this study a series of epoxy/silica nanocomposites were prepared by using nano silica particles which had different surface modifications. The morphology of the nanocomposite coatings was characterized by scanning electron microscopy SEM. The effects of the hydrophilic and hydrophobic feature of the nano particles on the Tg and anticorrosive properties of nanocomposite coatings were evaluate...

AIM The purpose of this study was to evaluate the effectiveness of three commercially available light emitting diode (LED) light curing units (LCU) (Elipar FreeLight--3M ESPE; UltraLume LED2--Ultradent; and Single V--BioArt) for polymerizing Z250-A3 composite (3M ESPE) using Knoop hardness, polymerization depth, and flexural strength properties. METHODS AND MATERIALS The XL 2500 (3M ESPE) LCU...

A method for improving adhesion between polymer films on Si substrates is described involving mechanical interlocking. Isotropic reactive ion etching (RIE) is applied to form pits in the Si substrate which fill upon application of a polymer via spinning. After curing, interpenetrating polymer lobes form a robust bond with the Si substrate. Adhesion improvements over films on smooth substrates a...

We describe a scalable method to fabricate nanopatterned bioinspired dry adhesives using colloidal lithography. Close-packed monolayers of polystyrene particles were formed at the air/water interface, on which polydimethylsiloxane (PDMS) was applied. The order of the colloidal monolayer and the immersion depth of the particles were tuned by altering the pH and ionic strength of the water. Initi...

This paper presents an experimental investigation on the effect of partial replacement of cement by metakalion by various percentages viz 0%, 10%, 20%, and 30% on the properties of high performance concrete, when it is subjected to magnesium sulphate attack. An aggregate binder ratio of 2 and different water binder ratios viz 0.3, 0.35, 0.40 and 0.45 was used in this investigation. Concrete spe...

This work describes a simple technique to produce porous ceramics with aligned porosity having very high permeability and specific surface area. SiOC-based compositions were processed from blends of three types of preceramic polymer and a catalyst, followed by curing and pyrolysis. The heating applied from the bottom of molds promoted the nucleation, expansion and rising of gas bubbles, and the...

This in-Vitro study was conducted to investigate the stain resistance of direct composite resin restorative materials with different polishing systems (diamond finishing and polishing burs, aluminium oxide disks and abrasive impregnated disks) in comparison to the material cured against a mylar strip. The composite resin materials investigated included Clearfil AP-X (hybrid), Filtek Z-250 (hybr...