Effect of nano clay and silver nano particles on the flexural strength and antimicrobial property of acrylic denture base resin– an invitro study

Polymethyl methacrylate (PMMA) has been commonly used as denture base material. However, repeated stress from masticatory action during function and impact force from accidental drop can result in fracture of the denture base. Thus, further improvements in the mechanical property of PMMA denture base material are still needed. This study aimed to provide us with an improved acrylic denture base resin which possesses better mechanical property and antimicrobial activity by addition of nano clay and silver nano particles. The objectives of the study are to evaluate the flexural strength and antimicrobial property of conventional PMMA denture base resin after incorporation of 3% nano clay and varied concentrations of silver nano particles. Materials and Methods: A total number of 60 specimens were included in the study. 30 rectangular specimens were fabricated for testing the flexural strength and 30 disc shaped specimens were fabricated for testing the antimicrobial property. Test specimens were divided into 3 groups based on the concentration of nano clay and silver nano particles in heat cure acrylic resin. These included a control group and two test groups with 3% nano clay and varied concentrations of silver nano particles. Results: One way ANOVA descriptive analysis showed significant difference after the incorporation of 3% nano clay and different percentage of silver nano particles in conventional PMMA denture base resin. The increasing order of flexural strength was as follows: Group B (3% nano clay and 0.5% silver nano particles) showed the least flexural strength followed by Group C (3% nano clay and 1% silver nano particles) and Group A (Control) showed the highest flexural strength. The increasing order of antimicrobial property is as follows: Group A (Control) showed the least antimicrobial property followed by Group B (3% nano clay and O.5% silver nano particles) and Group C (3% nano clay and 1% silver nano particles) showed the highest antimicrobial property. Conclusion: The flexural strength of conventional PMMA denture base resin after incorporation of 3% nano clay and 0.5% silver nano particles showed the least flexural strength. Incorporation of 3% nano clay and 1% silver nano particles showed higher flexural strength but lesser compared to the control group. The antimicrobial property of conventional PMMA denture base resin after incorporation of 3% nano clay and 0.5% silver nano particles showed lower antimicrobial property but higher compared to the control group. Incorporation of 3% nano clay and 1% silver nano particles showed the highest antimicrobial property. Clinical implications: This study provided a feasible approach of developing a modified acrylic denture base resin having sufficient flexural strength and possessing antimicrobial properties. The optimum microbial inhibition shown by the synthesized material can be considered to be an interesting material for scientific research of antimicrobial acrylic denture base resins.