Tehran University of Medical Sciences Frontiers in Biomedical Technologies 2345-5837 12 3 2025 07 01 479 484 Ola H. Hasan Prosthodontic Department, College of Dentistry, University of Baghdad, Baghdad, Iraq Zainab Saleh Abdullah Prosthodontic Department, College of Dentistry, University of Baghdad, Baghdad, Iraq 2023 08 20 2023 09 12 Purpose: This research aimed to evaluate how different concentrations of MgO nanoparticles influence the hardness, surface roughness, and SEM investigation of VerSiltal 50 silicone elastomeric materials that vulcanize at room temperature. Materials and Methods: Using different weight percentages of MgO nanoparticles, 60 samples were created (0%, 0.5%, and 1% by wt.). The analysis made use of thirty samples from each group. Tests for surface roughness and surface hardness were performed on two experimental groups that contained 0.5% and 1% weight of MgO nanoparticles. Descriptive statistics and analysis of variance with multiple comparison tests were used to evaluate the data, and significance was indicated by a P value < 0.05. Scanning electron microscopy was used to measure the surface topography (SEM). Energy Dispersive X-ray spectroscopy (EDS) can be used to determine the distribution of Magnesium Oxide within the VST-50 silicone matrix. Results: Surface roughness and hardness increased as the percentage of MgO nanoparticles increased from 0.5 wt. % to 1 wt. %, compared with those in the control group. The SEM test showed a good dispersion of the nanofillers and incorporation within the polymeric matrix of silicone. It showed that there was a slight little agglomeration of Nano filler particles as filler loading increased. Conclusion: Compared to the control group, the means for surface roughness and hardness increased significantly in the 0.5 and 1 wt.% MgO experimental groups. https://fbt.tums.ac.ir/index.php/fbt/article/view/803 https://fbt.tums.ac.ir/index.php/fbt/article/download/803/482