Hamadan University of Medical Sciences Avicenna Journal of Dental Research 2423-7582 17 2 2025 06 30 Evaluating the Effectiveness of a Synthetic Composite Polishing Paste on the Surface Roughness of Light-Curing Resin Composite: An In Vitro Study 124 129 10.34172/ajdr.2119 EN Morad Hedayatipanah https://orcid.org/0000-0003-1459-0964 Atousa Haghdoost https://orcid.org/0000-0002-2929-9726 Mohammad Ansaripour https://orcid.org/0009-0008-3798-4732 Mohammad Amin Dashti Malihe Safari Journal Article 10.34172/ajdr.2119 2024 11 06 2025 02 19 Background: Achieving a smooth and fine surface texture in resin composites is necessary. The study aimed to compare the influence of two polishing pastes on the surface roughness of three composite resins. Methods: To this end, 90 resin composite specimens (hybrid, micro-hybrid, and nano-hybrid types) were selected for analysis and divided into nine groups of 10. The specimens were polished for 30 seconds with Enamelize and manufactured polishing pastes. Then, surface roughness was assessed using profilometry. Eventually, a two-way analysis of variance with Tukey’s post-hoc test was used to analyze the data. Results: The smoothest surfaces (Ra=0.37 μm) were achieved with nano-hybrid composites polished using the manufactured paste. Conversely, the roughest surfaces (Ra=1.78 μm) were observed in the unpolished micro-hybrid group. Nano-hybrid composites demonstrated superior polishability compared to hybrid and micro-hybrid composites. Manufactured paste resulted in less roughness in all three composite groups. Conclusion: No statistically significant difference in surface roughness was observed between the Enamelize and manufactured polishing groups.