Preparation and characterization of Bis-GMA-free dental composites with dimethacrylate monomer derived from 9,9-Bis[4-(2-hydroxyethoxy)phenyl]fluorene

Abstract Objective Synthesize a new BPA-free monomer for use in methacrylate-based materials and evaluate critical properties of resin and composite materials based on the monomer. Methods Bis-EFMA was synthesized through reaction between 9,9-bis[4-(2-hydroxyethoxy)-phenyl]fluorene and 2-(methacryloyloxy)ethyl isocyanate. Experimental Bis-EFMA-based resin (Bis-EFMA/TEGDMA = 50/50, wt./wt.) and composite were prepared. Critical properties were investigated according to standard or referenced methods Bis-GMA/TEGDMA (50/50, wt./wt.) resin system, Bis-GMA-based composite and 3 M ESPE Filtek™ Z250 were used as controls. Results FT-IR and 1 H NMR spectra confirmed the structure of Bis-EFMA monomer. Cured resin materials: Bis-EFMA-based and Bis-GMA-based resins had nearly the same degree of conversion ( p >  0.05); Bis-EFMA-based resin had significantly lower shrinkage, water sorption and solubility, and cytotoxicity than Bis-GMA-based resin (p  p  > 0.05); Bis-EFMA-based composite had significantly lower shrinkage and solubility ( p  p  > 0.05), but lower compared to Bis-GMA-based composite ( p   0.05); Bis-EFMA-based composite had the deepest curing depth ( p  p  > 0.05), while FS became lower than that of Z250 ( p  p  p  > 0.05), higher than that of Bis-GMA-based composite ( p  p  Significance Bis-EFMA has potential as a substitute for Bis-GMA to prepare Bis-GMA-free dental composites.