Fig. 2

ΔL*, Δa* e Δb* values per experimental group. F test (ANOVA) has not shown a significant difference in the mean values of Δa* (P = 0.371) or Δb* (P = 0.191). Comparing different propolis nanosuspensions, ΔL* values are significantly different between RP3 before etching and RP3 after etching (P = 0.023). There was also a significant difference between RP3 and RP1 (P = 0.031) before etching. There was no statistically significant difference for all other comparisons (P > 0.05). RP1, 1% of red propolis micellar nanocomposite; RP6, 0.6% of red propolis micellar nanocomposite; RP3, 0.3% of red propolis micellar nanocomposite