Characterization of an experimental resin composite organic matrix based on a tri-functional methacrylate monomer.

This study evaluated the potential of a tri-functional monomer (trimethylolpropane trimethacrylate -TMPTMA) for inclusion in a dental composite organic matrix. Initially, four ternary matrixes with different concentrations (wt%) of bi-functional monomers [BisGMA (G), Bis-EMA (E) and TEGDMA (T)] were analyzed: GET523, GET532, EGT523 and EGT532 (the numbers (n) represent n×10 wt% of each monomer). The following properties were evaluated: degree of conversion, flexural strength, elastic modulus, hardness, absorption, solubility, diffusion coefficient of water and crosslink density. Based on the best overall results obtained for EGT532, all properties were re-evaluated in a matrix where TEGDMA (T) was replaced by a tri-functional monomer, TMPTMA (A)-EGA532. EGA532 presented the best results for flexural strength, hardness, absorption and crosslink density. EGT523, EGT532 and EGA532 presented the lowest diffusion coefficients of water. The overall results indicated that TMPTMA could be useful in formulating organic matrixes suitable for dental restorative composites.