Synthesis of organic–inorganic hybrid compounds based on Bis-GMA and its sol–gel behavior analysis using Taguchi method

Objectives The aim of this study was the synthesis of organic–inorganic hybrid compounds based on Bis-GMA and incorporation of them into conventional Bis-GMA/TEGDMA dental resins. This was achieved by the synthesis of Bis-GMA bearing two –Si(OEt)3 reactive groups (a bridged monomer) and subsequent hydrolysis–condensation reactions with TEOS, in TEGDMA media. Methods The structure of the bridged monomer was characterized by using FTIR technique. The sol–gel behavior of the aforementioned hydrolysis–condensation reactions was investigated by using an experimental design based on the Taguchi method. Therefore, amounts of the bridged monomer, TEOS and TEGDMA in the gelation process were optimized in order to achieve the maximum gel content without complete gelation of the mixture. Results It was found that the amount of the bridged monomer has the major effect with the amount of TEGDMA having a minor effect. The cross-over effect between the constituents of the mixture was also investigated to be negligible. Significance The organic–inorganic hybrids developed based on Bis-GMA can be combined with commonly used methacrylate light-curable dental resins.