Objectives: This research evaluated the surface and interfacial roughness of three nano resin composites with different polishing techniques after thermocycling.
Materials and Method: Class-V cavities of dimension (4mm mesiodistally, 2mm occluso-gingivally and 2mm cavity depth) were prepared on buccal surfaces of 45 human premolars either restored utilizing Omnichroma (Tokuyama, Japan), Harmonize Universal (Kerr, USA) or Filtek Z350XT (3M Oral Care, USA) then either be left unpolished or polished using PoGo disc micro-polishers (Dentsply, USA) or Sof-Lex spiral wheels (3M ESPE, USA). A profilometer was utilized to measure the surface roughness (Ra) after thermocycling. Repeated measures ANOVA and Bonferroni's post-hoc tests were utilized for statistical analysis. The significant level was set at (P ≤ 0.05).
Results: Harmonize Universal showed the statistically significantly highest mean Ra (0.645 μm) followed by Filtek Z350XT (0.594 μm). Omnichroma showed the statistically significantly lowest mean Ra (0.539 μm). Polyester strip showed the statistically significantly highest mean Ra (0.73 μm) followed by Sof-Lex spiral wheels (0.627 μm). PoGo disc micro-polishers showed the statistically significantly lowest mean Ra (0.422 μm). Composite surface showed statistically significantly lower mean Ra (0.222 μm) than interface (0.556 μm).
Conclusions: Omnichroma is a good choice material for the clinical use because it has better surface polishability after thermocycling compared to Harmonize Universal and Filtek Z350XT.