Effect of finishing procedures and beverages on the color stability of direct Composite esthetic restorative material-an in vitro study

Aim: Evaluation of the effect of composite polishing systems and the type of storage solutions on
color stability of resin-based direct composite at various time intervals in vitro.
Methods and Material: Forty discs were prepared using methacrylate-based nanofilled composite
and polished with one of the two groups: aluminum oxide discs (Super-Snap) and diamond
impregnated polishing wheels (Compomaster). Profilometric analysis and SEM observations were
performed for determining the surface roughness. Samples were then sub-grouped (n=10) and
immersed in beverages (distilled water, coffee, cola, orange juice) for 10 minutes each day. Color
coefficients (CIE L*a*b*) were measured by a spectrophotometer before and after the immersions;
after 24 hrs, 36 hrs and one week.
Statistical analysis: The results were compared among the four groups by two-way analysis of
variance and Tukey’s t-test (p ≤ 0.05). Regression analysis was carried out to test if any correlation
existed between color change and surface roughness.
Results: Significant correlation was found between the effects of surface roughness and color change
of composite resins. Super-Snap system resulted in the best surface finish and lowest degree of color
change. Highest level of mean color change was observed in coffee solution (P < 0.05) followed by
cola and orange juice with maximum staining shown after one week.
Conclusions: Composite resin tested showed an acceptable color change after immersion in different
beverages.