Flexural properties and impact strength of denture base resins reinforced with micronized glass flakes

OBJECTIVES: To investigate the effect of the addition of glass flakes on physical properties of conventional heat cure denture base resins and to compare it with a high impact strength denture base resin. MATERIALS AND METHODS: Test specimens were divided into Group 1 - poly (methyl methacrylate) (PMMA) (Trevalon), Group 2 - Trevalon HI, Group 3 -5% glass flake +95% PMMA (Trevalon), Group 4 -10% glass flake +90% PMMA (Trevalon), and Group 5 -20% glass flake +80% PMMA (Trevalon). For glass flake modified groups, part of PMMA (powder) was substituted with the same weight of glass flake (GF003 m) as required, to bring it to 100% powder. Flexural strength was tested using three-point bending test and impact strength with Izod type impact tester. RESULTS: Plain PMMA (Trevalon), showed the highest value of flexural strength followed by Trevalon HI. Trevalon HI (highly cross-linked PMMA) group showed the highest value of impact strength. CONCLUSION: Flexural strength of unmodified PMMA denture base resin decreases with increase in the concentration of glass flakes. Impact strength does not show any significant change at 5% concentration of glass flakes and impact strength significantly reduces with the addition of glass flakes in 10% and 20%.