OBJECTIVES This study evaluated the effect of lactic acid and acetic acid on the microhardness of a silorane-based composite compared to two methacrylate-based composite resins. MATERIALS AND METHODS Thirty disc-shaped specimens each were fabricated of Filtek P90, Filtek Z250 and Filtek Z350XT. After measuring of Vickers microhardness, they were randomly divided into 3 subgroups (n = 10) and ...

Background: To evaluate and compare the microhardness of deciduous teeth treated with nano-hydroxyapatite and calcium sucrose phosphate after iron drop exposure. Material and Methods: Twenty healthy anterior deciduous teeth were collected and stored in 0.9% saline solution at room temperature. All the teeth were immersed in artificial saliva in an incubator shaker at 37° for an hour and then su...

STATEMENT OF THE PROBLEM Acidic foods and drinks can erode composite resins. Silorane-based composite is a new low shrinkage composite with higher hydrophobicity which might resist the erosive effect of beverages. PURPOSE The aim of this study was to determine the effects of 100% orange juice and non-alcoholic carbonated beer on microhardness of a silorane-based composite in comparison with t...

This study examined the surface microhardness of four kinds of resin composites with different fillers and resin matrices. Ten specimens of 2 mm thickness and 4 mm diameter of each resin composite were polymerized using a halogen light, a blue light-emitted diode, and a plasma arc unit. Microhardness evaluation was performed at top and bottom surfaces for each specimen using a Vickers microhard...

BACKGROUND A manifold increase in the consumption of aerated beverages has witnessed a twin increase in tooth wear and raised demand for esthetic restorative materials. This study aimed to evaluate the surface microhardness changes of esthetic restorative materials following treatment with aerated beverages in an in-vitro situation. MATERIAL AND METHODS The initial surface microhardness of th...

BACKGROUND This study aimed to evaluate the flexural strength and microhardness of three different anterior composites after 10 000 thermocycles. MATERIAL AND METHODS The mechanical properties of a nano-fill composite (Filtek Ultimate Universal Restorative (FUR) (Enamel)), a nano-hybrid composite (Clearfil Majesty ES2 (ES2) (Enamel)), and a micro-hybrid composite (G Aenial Anterior (GAA)) wer...

The aim of the study was to determine microhardness of high- and low-viscosity bulk-fill composite resins and compare it with conventional composite materials. Four materials of high-viscosity were tested, including three bulk-fills: QuiXfi l (QF), x-tra fi l (XTF) and Tetric EvoCeram Bulk Fill (TEBCF), while nanohybrid composite GrandioSO (GSO) served as control. The other four were low-viscos...

OBJECTIVES To evaluate the effects of three acids on the microhardness of set mineral trioxide aggregate (MTA) and root dentin, and cytotoxicity on murine macrophage. MATERIALS AND METHODS OrthoMTA (BioMTA) was mixed and packed into the human root dentin blocks of 1.5 mm diameter and 5 mm height. Four groups, each of ten roots, were exposed to 10% citric acid (CA), 5% glycolic acid (GA), 17% ...

BACKGROUND Surface microhardness is a physical property which access the effect of chemical and physical agents on hard tissues of teeth, and a useful way to examine the resistance of fluoride treated enamel against caries. The purpose of this study was to evaluate microhardness of enamel following pH-cycling through demineralization and remineralization using suspensions of dentifrices with di...

This study evaluated the influence of curing method and storage condition on the microhardness of dual-cure resin cements: Panavia F 2.0 (PF) and Nexus 2 (NX). The specimens were either light-cured (LC) or chemically cured in darkness (CC). After 24 hours of storage in dry chamber (Dry) or distilled water (DW), the specimens were sectioned and polished. The microhardness of resin cement matrix ...