A novel approach to reinforce provisional material using silica gel powder

Aim: To evaluate a novel approach for reinforcing 2 types of provisional restoration materials [polymethylmethacrylate (PMMA) and bis-acryl resin] with different concentrations of silica gel powder (0%, 0.5%, 1%, 1.5%, 3%, 5%, 10% by weight). Methods: A total of 60 rectangular fracture toughness specimens were prepared in this study according to the ISO 13586 Standard with dimensions of 2 mm × 5 mm × 25 mm. The specimens were divided into 2 groups according to the materials used PMMA or bis-acryl. Each subgroup was divided into 6 subgroups according to the different silica gel concentrations (0%, 0.5%, 1.5%, 3%, 5%, and 10% by weight) added where the 0% subgroup was used as a control group. Fracture toughness for the specimens was determined by loading the specimens in a universal testing machine. Results: The results showed that addition of 0.5% by weight of the silica gel powder for PMMA recorded the highest mean value (2.69 ± 0.08 MPa•m1/2) and this was statistically significant. Conclusion: Within the limitation of this study it was concluded the addition of 0.5% by weight silica powder gel could increase the fracture toughness of PMMA.