New composites with improved thermal stability, mechanical and dielectric properties were developed, which consist of 2,2!-diallylbisphenol A (DBA)/4,4!-bismaleimidodiphenylmethane (BDM) resin and a new kind of organic/inorganic mesoporous silica (MPSA). Typical properties (curing behavior and mechanism, thermal stability, mechanical and dielectric properties) of the composites were systematica...

OBJECTIVES The aim of the study was to develop a new kinetic model for the shrinkage-strain rates of dental resin composites. The effect of filler content on the shrinkage-strain kinetics and degree of conversion of dental composites was also investigated. METHODS A resin matrix containing 65 wt.% Bis-GMA and 35 wt.% TEGDMA was prepared. 0.5 wt.% camphorquinone and 0.5 wt.% dimethyl aminoethy...

Wood liquefaction using an organic solvent and an acid catalyst has long been studied as a novel technique to utilize biomass as an alternative to petroleum-based products. Oxalic acid is a weaker organic acid than a mineral acid and wood liquefaction with oxalic acid as a catalyst will result in a higher amount of wood residue than that with a mineral acid. Yet the wood residue can be used as ...

Silver and gold have been used for centuries as antimicrobial agents. The aim of the study was to investigate diametral tensile strength, microhardness, ion release and light transmission of experimental resin composites. Flowable dental composite SDR (Dentsply, United Kingdom) was modified by nanogold, nanosilver and silica addition. The metal ion release, light transmission study, microhardne...

BACKGROUND The aim of this study was to evaluate the Vickers surface micro-hardness and the depth of cure of two bulk-fill resin composites and one incremental-fill resin composite. MATERIAL AND METHODS Two Bulk-fill dental resin composites (X-tra Fil, Voco; Sonic-FillTM 2, Kerr Corporation) and an incremental-fill dental resin composite (Filtek™ Z250 XT, 3M ESPE) were used. Sixty cylindrical...

The novel quaternary ammonium bromide (QAB)containing oligomers were synthesized and applied for developing an antibacterial resin composite. Compressive strength (CS) and S. mutans (an oral bacteria strain) viability were used to evaluate the mechanical strength and antibacterial activity of the formed composites. All the QAB-modified resin composites showed significant antibacterial activity ...

Flexible composite films were produced by impregnating aqueous phenol formaldehyde (PF) resin into water-swollen cellulose nanofibril (CNF) films. CNF films were prepared using a pressurized filtration method in combination with freeze drying. The freeze-dried films were swollen with water then impregnated with PF resin by soaking in aqueous resin solutions of varying concentrations. Small amou...

INTRODUCTION Today, development of materials technology using biomass is expected for creation of a sustainable society. Especially, the composite consisting of plant-based natural fibers and biodegradable resin, so-called the fully-green composites, is much expected for practical use. So far, we made textile green composites using biodegradable resin and plain woven ramie fabric and explored t...

PURPOSE More than five hundred million direct dental restorations are placed each year worldwide. In about 55% of the cases, resin composites or compomers are used, and in 45% amalgam. The longevity of posterior resin restorations is well documented. However, data on resin composites that are placed without enamel/dentin conditioning and resin composites placed with self-etching adhesive system...

introdouction: bleaching has become a common treatment for improving the appearance of natural teeth. however, the need to protect dental restorations from bleaching agent exposure is inevitable, as these agents may change the color of restorative materials by oxidation. filtek p90 composite resin has recently been introduced with the aim of decreasing polymerization shrinkage. the purpose of t...