Synthesis, characterization and evaluation of new fluorene-based dimethacrylates for formulating dental composites

This study focused on the preparation and evaluation of several new fluorene-based dimethacrylates, as possible intermediates to formulate improved dental composites. As the first step towards modification of the composite formulation, the new monomers and unfilled resin matrix were prepared. The formulated and visible light-cured materials were found to be more hydrophobic, along with having higher wet (water saturated) glass transition temperatures (Tg) than the commonly used matrix resins based on 2,2-bis(4(2-hydroxy-3-methacryloxy-propyloxy))-phenylpropane (Bis GMA). In addition, the new matrix resins exhibited greater compressive strength, along with greater resistant to creep and fracture. Finally, the results suggested a correlation may exist between creep and the homologous temperature (T/Tg) of the light-cured neat resins, where the T/Tg may be used to compare the mechanical properties of different materials at various temperature.