Introduction: Composite resins are one of the most commonly used tooth-colored aesthetic restorative materials, which may undergo surface degradation when exposed to oral conditions, leading to significantly altered physical and mechanical properties. The aim of the present study was to evaluate surface degradation of posterior restorative nanocomposites following aging with simulated oral conditions on scanning electron microscopy (SEM) evaluation. Materials and Methods: For the present in-vitro study, five single shade resin composites were selected, while they were subjected to surface roughness analysis and evaluation of morphological surface characteristics after immersion into various food-simulating liquids (FSLs) using SEM evaluation. Results: SureFil (SDR Flow+) revealed maximum surface roughness values in all cases when subjected to aging procedure using air (control group) (0.045 ± 0.004 µm), distilled water (0.058 ± 0.006 µm), 50% ethanol (0.078 ± 0.007 µm), and 0.02 normality (0.02 N) citric acid (0.064 ± 0.007 µm). Again, Filtek Z350 XT revealed the least surface roughness values when subjected to aging procedure using air (0.031 ± 0.004 µm), while Clearfil Majesty Posterior revealed the least surface roughness values in all other cases when subjected to aging procedure using distilled water (0.036 ± 0.005 µm), ethanol (0.031 ± 0.004 µm), and 0.02 normality (0.02 N) citric acid (0.038 ± 0.005 µm). Conclusions: Posterior restorative nanocomposites are constantly exposed to different food environments in the actual in-vivo conditions, which may severely affect their surface characteristics. Considering the given facts and the in-vitro nature of the present study, further research is mandated to investigate the changes in the properties of these materials under different storage environments and temperatures to come to valid conclusions.
Almutairi et al. (Tue,) studied this question.