ABSTRACT
One of the most widely used materials in prosthetic dentistry is polymethyl methacrylate. Despite it's popularity, the primary problem is it's poor flexural strength and low impact strength. The aim of this study was to compare the flexural strength of unreinfored heat-cured polymer [group 1] with wire-reinforced polymer [group 2] and with glass fiber-reinforced polymer [group 3]. In this invitro experimental study 24 uniform specimens of 65.0x10.0x3.5 mm were fabricated as the manufacturer's recommendation and were assigned to 3 groups of eight. In the first and second group the samples were reinforced by glass fibers and wire respectively. The samples speciemens of third group were made of heatcure resin and served as control group. All of them were loaded up to failure, using a three-point bending test, and then the flexural strength was calculated. Data were analysed by one way analysis of variance [ANOVA]. The results showed that wire and fiber-reinforced polymers have higher flexural strength than unreinforced polymer. The one-way ANOVA revealed significant difference between group 1 and other groups statistically [P<0.05] however, there was no significant differences between groups 2 and 3. Based on the achieved results, we can use wires or fibers in order to reinforce polymer, regarding that glass fibers can be used as reinforcement of denture acrylic resin in patients who care about esthetic