Investigating the Effect of Hydroxyapatite Nanoparticle Addition on Mechanical Behavior and Fatigue Life of Polymethylmethacrylate/Hydroxyapatite Restorative Nanocomposite Material

The current investigation integrates numerical and experimental methodologies to examine the fatigue properties of notched PMMA/HA dental nanocomposites enhanced with nanoparticles. Standardized notched specimens, incorporating varying percentages of nanoparticles, were produced for tensile and fatigue assessments. The experimental findings indicated notable enhancements in the mechanical and cyclic characteristics of the nanocomposite specimens when compared to pure PMMA. The Brown–Miller criterion was employed to analyze the life cycles, supplementing the experimental approach. The fatigue tests demonstrated that the life cycle at lower applied forces increased with higher nanoparticle concentrations, yielding average cycles of 31, 37, 44, and 46 thousand for 0%, 0.5, 1, and 1.5% nanoparticle content, respectively. A strong correlation was observed between the numerical and experimental outcomes, confirming the efficacy of the Brown–Miller criterion in predicting the life cycles of these nanocomposites.