A study was performed to improve dental materials by adding gold nanoparticles to a conventional PMMA resin used for dentures, giving this material an antimicrobial property. The addition of gold nanoparticles showed a significant antibiofilm effect against the microbial biofilm formation. This property may prevent or decrease the occurrence of the most frequent complications when using removable dental prosthetics, such as denture stomatitis, and lower the quantity of biofilm formation on these devices. Using PMMA with gold nanoparticles for dentures thus has the ability to reduce treatments of patients suffering from denture stomatitis with antibacterial drugs and to prevent the development of further complications associated with the formation of biofilm on the dentures.