Effect of microwave disinfection on mechanical properties of denture base acrylic resin

The microwave oven was used for sterilizing dentures contaminated with Candida albicans and other communicable diseases instead of disinfectant solutions. This study was carried out to evaluate the flexural properties, toughness, and impact strength of heat-cured acrylic resin sterilized by microwave oven either immersed in water or non-immersed for 5 and 15 min at full power. The results indicated that the microwave oven sterilization technique resulted in reduction of the load necessary to fracture the specimens, deformation at fracture, transverse strength, modulus of elasticity except disinfection at 5 min dry condition, toughness, and impact strength. This study concluded that the microwave oven is not acceptable for sterilization of dentures because of its weakening effects on the dentures that prone for fracture during clinical use. This method of sterilization increased the brittleness of acrylic resin specimens.