Abstract :
Background: Enhancing the longevity and functionality of dental prostheses necessitates the development of robust and efficient denture-based polymers to pave itself for gerontology. Recent advancements have focused on incorporating zinc oxide (ZnO) and biodegradable polylactic acid (PLA) nanofillers to improve the properties of these resins under conditions that simulate the oral environment.Aim: This study aims to evaluate the degradation rate of dental polymers infused with bio-based PLA nanofillers in the presence of artificial saliva, simulating the clinical performance of denture base materials, for rehabilitation potential in geriatric population.Materials and Methods: Forty denture base resin samples were prepared using 10% polylactic acid (PLA) and 3% zinc oxide (ZnO) nanofillers in accordance with ISO 20795-1:2013 guidelines. The samples were incubated for 37 days at 37 ± 0.5°C and submerged in artificial saliva at pH 7 to replicate oral conditions. Evaluations included light transmittance, pH fluctuation, and dimensional accuracy. Post-incubation, direct microscopy assessed bacterial and fungal development. Statistical analysis was performed using IBM SPSS version 26.0.Results: Dimensional accuracy tests showed no significant difference between the PLA-ZnO and control groups, with mean dimensional changes of 65.86 and 66.07, respectively (p = 0.062). pH measurements before and after incubation indicated no change due to PLA-ZnO nanofillers. The PLA-ZnO group exhibited greater water absorption, with a mean swelling degree of 1.57 compared to 1.43 in the control group (p = 0.05). Microbiological analysis showed no bacterial or fungal growth on the samples. Additionally, the PLA-ZnO group demonstrated a significant increase in light transmittance at 540 nm, with a mean intensity of 658.07 compared to 328.20 in the control group (p = 0.05).Conclusion: PLA-ZnO composite resins exhibit enhanced antibacterial properties while maintaining light transmittance. However, they show altered optical characteristics and increased swelling, indicating the need for further optimization.
Keyword :
Artificial saliva, Light transmittance, Denture resins, Dimensional accuracy, Mechanical properties, Nanofillers, Polylactic acid, Zinc oxide