Abstract Poly(methyl methacrylate) (PMMA) is the most widely used denture base material but exhibits limited fracture resistance under functional loads. This study investigates the effect of incorporating zirconia (ZrO 2 ) and polyether ether ketone (PEEK) nanoparticles on the structural and mechanical properties of PMMA. Thirty rectangular heat-cured PMMA specimens (65 × 10 × 2.5 mm) were divided into three groups: Group C (control): unmodified PMMA; Group P: PMMA with 5% PEEK nanoparticles; and Group ZP: PMMA with a hybrid of 2.5% ZrO 2 and 2.5% PEEK nanoparticles. Nanoparticle morphology was analyzed by field emission scanning electron microscopy (FESEM), showing PEEK sizes between 26 and 100 nm and spherical ZrO 2 with a mean diameter of 47 nm. Energy-dispersive X-ray spectrometry (EDXS) was performed on ZrO 2 only. FTIR analysis confirmed interfacial bonding in the hybrid composite. Flexural strength was measured via a three-point bending test. The ZP group exhibited the highest flexural strength (mean: 139.78 MPa), significantly outperforming both P and C groups ( p < 0.05), with no significant difference between P and C. The synergistic addition of ZrO 2 and PEEK nanoparticles significantly improved the mechanical and structural behavior of PMMA, offering a promising strategy to enhance durability and clinical performance of denture base materials in prosthodontics.
alrais et al. (2026) studied this question.