Tehran University of Medical Sciences Frontiers in Biomedical Technologies 2345-5837 13 3 2026 09 01 659 675 EN Ahmed Jameel Mashloosh Department of Prosthodontics, Collage of Dentistry, University of Baghdad, Baghdad, Iraq Faiza M. Abdul-Ameer Department of Prosthodontics, Collage of Dentistry, University of Baghdad, Baghdad, Iraq 2024 06 23 2024 08 19 Purpose: Silicone elastomers are extensively used in the fabrication of maxillofacial prostheses, yet their characteristics are far from optimal. Key factors necessitating the frequent re-fabrication of these prostheses include their limited lifespan and the deterioration of both their color and mechanical properties. This study aims to evaluate the impact of copper oxide nanoparticles (CuO NPs) on the mechanical properties of VST 50F maxillofacial silicone. Materials and Methods: A total of 120 specimens were prepared, with 30 specimens for each test. Five mechanical tests—tear strength, tensile strength, percentage of elongation, Shore A hardness, and surface roughness—were conducted with two experimental groups and a control group for each test. Results: Statistical analysis revealed a significant increase in tear strength for both experimental groups (P < 0.05). Specifically, Group B showed a 12.5% increase with a mean value of 23.89 kN/m, while Group C demonstrated a 21.57% (25.81 kN/m) increase compared to the control group (21.23 kN/m). Tensile strength also improved, with Group B exhibiting a 13.9% increase with a mean value of 4.655 Mpa and Group C exhibiting a 14.0% (4.660 Mpa) increase compared to the control group (4.08 Mpa). Additionally, Shore A hardness increased by 7.98% (33.34 IU) for Group B and 14.58% (35.37 IU) for Group C, alongside a significant decrease in the percentage of elongation—Group B decreased by 3.36% (864.80) and Group C by 3.80% (860.86) compared to the control group (894.87). However, there was a non-significant increase in surface roughness (P > 0.05). Group B displayed a 4.48% (0.303 µm) increase, while Group C showed a 5.17% (0.305 µm) increase compared to the control group (0.290 µm). Conclusion: The results of this study suggest that CuO NPs can improve silicone elastomers' shortcomings; however, further studies are required to fully comprehend these NPs' long-term effects and how they affect other silicone material physical properties. https://fbt.tums.ac.ir/index.php/fbt/article/view/1047 https://fbt.tums.ac.ir/index.php/fbt/article/download/1047/587