Studies on the preparation and mechanical properties of esthetic polymeric dental restoratives using silane treated silica microfiller via freeze‐drying

Abstract Polymeric dental restorative composites were prepared using silica filler where the surface was treated with γ‐methacryloxypropyltrimethoxysilane and decanted solvents by the freeze‐drying method. This treatment improved the miscibility of the filler with 2,2′‐bis‐[4‐(methacryloxy‐2‐hydrbxypropoxy)‐phenyl]‐propane/triethyl‐eneglycoldimethacrylate resin matrix and enhanced the esthetic properties of the composite. Diametral tensile strength (DTS) and flexural strength (FS) of the dental composite were measured, and the effect of drying methods in the surface treatment of filler on the mechanical properties of the composite was also investigated. Dental restorative composites prepared by the freeze‐drying method showed substantially higher DTS and FS values than those prepared by the conventional heat‐drying method. This resulted in increasing the loading percentage of filler in the resin matrix, and thereby, DTS values were increased dramatically. Dispersion of silica filler in the resin matrix and surface characteristics were examined by scanning electron microscopy. Various esthetic grades of dental composites were successfully prepared using iron oxide pigments, and its Hunter L. a. b. values of vita color‐shade were also investigated.