The polymerization shrinkage of composite resins may affect negatively the clinical outcome of the restoration. Extensive research has been carried out to develop new formulations of composite resins in order to provide good handling characteristics and some dimensional stability during polymerization. The purpose of this study was to analyze, in vitro, the magnitude of the volumetric polymeriz...

introduction: in orthodontic therapy ,different materials are used and their presence in oral cavity may modify their properties. the purpose of this study was to evaluate the direct and indirect biocompatibility of three orthodontic composite resins on culture of human oral fibroblasts. methods: this was an interventional experimental study. the biocompatibility of three orthodontic composite ...

objectives: the aim of this study was to compare polymerization depth of two bulk-fill and one conventional composite cured for different times. methods: this in vitro experimental study was conducted on 54 composite samples (2×4×10mm) fabricated of tetric n-ceram bulk-fill, x-tra fil bulk-fill, and grandio conventional composite cured for 20, 30, and 40 seconds. the microhardness of samples wa...

Composites resins are the most popular restorative materials providing very good esthetics and long period of good clinical performance. Depth of cure of composite resins is crucial in determining the maximal increment thickness when restoring tooth cavities. In restorations with conventional composite resins the thickness of each increment has been defined as up to 2 mm. Bulk fill composite re...

objectives: color change of composite restorations is well known to dentists. however, the effect of commonly consumed drinks on discoloration of composite resins has yet to be determined. this study sought to assess the color change of a nanofilled (premise) and a flowable composite resin (premise flowable) following simulated consumption of tea, cola, iron drops and multivitamin syrup. materi...

background and aim: in vitro studies have revealed a direct association between resin content and cytotoxicity of resin composites; but implantation studies in this regard are sparse. this study investigates the relationship between filler content of composite resins and biocompatibility. materials and methods: this study was conducted using 18 male wistar rats (180-200g), 1 nano-hybrid (prime-...

BACKGROUND Bisphenol A (BPA) is an endocrine disruptor with potential toxicity. Composite resins may not contain pure BPA, but its derivatives are widely used. Several studies found doses of BPA or its derivatives in saliva or urine of patients after composite resin placement. OBJECTIVE The aims of this study were to establish an exhaustive list of composite resins marketed in Europe and thei...

OBJECTIVE Bleaching agents may not be safe for dental materials. The purpose of this in-vitro study was to evaluate the effects of Opalescent Quick "in-office bleaching gel" containing 35% carbamide peroxide on the surface roughness and hardness of microfilled (Heliomolar) and hybride (Spectrum TPH) composite resins. MATERIALS AND METHODS Twenty specimens of Spectrum TPH composite resins and ...

The aim of this study is to evaluate the effect of preheating on composite resins’ mechanical and physical properties. Preheating of composite resins positively affects the degree of conversion, viscosity, microleakage, marginal adaptation, microhardness and color change however, the flexural strength is adversely affected.  

This study was conducted to examine the ultrastructures of eight recently improved light-cure restorative composite resins with scanning and transmission electron microscopes (SEM and TEM). Additionally, Vickers hardness, volume/weight fraction of filler, and chemical composition were analyzed. Composite resins selected for evaluation were Beautifil II, Clearfil AP-X, Clearfil Majesty, Estelite...