A triethylene glycol dimethacrylate- free dental composite for reduced water-sorption and shrinkage

Abstract

A number of new liquid urethane-based oligomers were synthesized, characterized and used to formulate the dental composites. Compressive strength and viscosity were used as a screen tool to evaluate the formed composites. Commercial available bisphenol A glycidyl methacrylate and urethane dimethacrylate-based systems were used as controls. Degree of conversion, shrinkage, water-sorption, solubility, flexural strength and diametrial tensile strength were evaluated. The results show that using mixed acrylate/methacrylate or methacrylates with different length to derivatize diisocyanates could be a good strategy to synthesize urethane-based oligomers in a liquid state. The developed triethylene glycol dimethacrylate-free urethane-based composites showed significantly reduced water sorption and solubility, decreased shrinkage and enhanced mechanical strength as compared to commercial resin-based ones.