Effect of replacing UDMA by a new tetramethacrylate monomer on the properties of dental resin composite

The aim of this study is to synthesize the tetramethacrylate monomer (TIMA) and evaluate its effect as a substituent for UDMA in the formulation of photopolymerizable dental resin composites (DRC). H-1 NMR, C-13 NMR and FTIR spectroscopies corroborate the chemical structure of the TIMA monomer. The experimental composite resin is a mixture of TIMA/TEGDMA monomers and silanized inorganic filler while, the control resin is a mixture of UDMA/TEGDMA and filler. The double-bond conversion, polymerization kinetics, volumetric shrinkage, aqueous sorption, solubility, mechanical properties, and cell viability are studied. The flexural strength of the composite resin formulated with TIMA monomer does not show statistical differences compared to the control (p > 0.05). However, formulations with the TIMA monomer presented higher elastic modulus (2425.37 MPa) and lower degree of conversion 38.5%, (p < 0.05). The differences in the water sorption, water solubility and volumetric shrinkage are not statistically significant between the groups (p > 0.05). Finally, the cell viability test show that the experimental resin formulated with TIMA monomer exhibited a cellular viability close to 100%. Due to its characteristics, TIMA monomer could be considered an alternative to UDMA in the composite resins with applications in dentistry.