<p>Incorporating nanoparticles has been found to improve certain mechanical properties of glass-ionomer cements (GICs). This study extended the investigation to include the surface topography and microhardness of GICs using two conventional materials (3M ESPE™ Ketac™ Universal and GC Fuji TRIAGE^®). Nanoparticulate aluminum oxide (Al₂O₃), zirconium oxide (ZrO₂), and titanium dioxide (TiO₂) were incorporated into each cement at concentrations of 2, 5, and 10 wt%. A total of 120 disc-shaped specimens were prepared. Samples were divided into control and experimental groups based on nanoparticle type and concentration. Following storage in saline solution, specimens were analyzed at 1 and 21 days. Surface topography was evaluated using Atomic Force Microscopy (AFM), and microhardness was measured using the Vickers hardness test (VHN). Results showed that the 5 wt% concentration of TiO₂ and ZrO₂ generally provided the most favorable enhancement in microhardness for both materials. Conversely, the 10 wt% concentration often led to increased surface porosity and a subsequent reduction in hardness. AFM analysis revealed that nanoparticle loading increased surface roughness, with Ketac™ Universal exhibiting higher baseline roughness than Fuji TRIAGE^®. We conclude that the incorporation of 5 wt% TiO₂ or ZrO₂ nanoparticles significantly improves the microhardness of GICs, whereas higher concentrations (10 wt%) compromise surface integrity due to particle agglomeration.</p>