Objective: Clinicians use different shades of restorative materials to mimic the natural teeth color. However, the effect of these shades on the restoration properties was unclear. Thus, the aim of the present study was to assess the effect of different shades of resin nano-ceramic on surface roughness before and after aging.
Materials and methods: Twenty rectangular specimens of 1±0.05 mm thickness were obtained from Lava Ultimate resin nano-ceramic blocks with two different shades (B1 and C2); n = 10. All specimens were polished and subjected to accelerated aging using autoclave for 6 hours. The surface roughness was assessed using digital microscope before and after aging. Surface morphology analysis was performed using a scanning electron microscope (SEM). After testing for normality, the collected data revealed parametric distribution and were expressed as mean and standard deviation (SD). Data were statistically analyzed using independent t-test and Paired t-test at a level of significance (P  0.05).
Results: Specimens with C2 shade showed statistically insignificant higher surface roughness compared to B1 shade before and after aging. Aging caused significant changes in the surface roughness in both groups, with changes in the surface microstructure.
Conclusions: The shade of resin nano-ceramic does not affect the surface roughness. Aging represents an important factor that can affect surface roughness.