Enhancement of Flexural Strength in Polymethylmethacrylate (PMMA) Through the Incorporation of Graphene Nanoparticles: A Comparative In Vitro Study

Abstract Background Polymethylmethacrylate (PMMA) is a common material in dental prosthetics, but its mechanical limitations, particularly in flexural strength, can affect its performance. Graphene nanoparticles, known for their exceptional mechanical properties, present a potential solution to enhance PMMA’s strength.Aim This study investigates the impact of incorporating graphene oxide (GO) and reduced graphene oxide (RGO) nanoparticles into PMMA on its flexural strength, comparing the effects of different nanoparticle concentrations.Materials and Methods Seventy heat-polymerized PMMA specimens (65 × 10 × 3 mm) were prepared following ISO 1567 standards. These specimens were divided into three groups: Control (no nanoparticles), Experimental Group A (GO), and Experimental Group B (RGO). Each experimental group was further subdivided based on the nanoparticle concentration: 0.10g, 0.20g, and 0.30g. Flexural strength was measured using a three-point bending test on a Universal Testing Machine with a crosshead speed of 1.50 mm/min and a span length of 40 mm. Data were analyzed using ANOVA and post-hoc Tukey-HSD tests.Results The control group recorded a mean flexural strength of 49.25 N. Incorporating GO and RGO nanoparticles significantly improved PMMA's flexural strength, with the highest strength observed in the RGO 0.30g group, showing a mean value of 213.6 N.Conclusion Reinforcing PMMA with graphene nanoparticles, including GO and RGO at various concentrations, significantly enhances its flexural strength compared to unreinforced PMMA. These findings highlight the potential of graphene-based nanoparticles to improve the durability of dental materials, offering superior mechanical properties critical for long-term clinical use.