Vol. 4, Issue 4, Part B (2018)

Materials and Methods: Seventy two disc shaped were fabricated, with a diameter of 12 mm and a thickness of 2 mm from each porcelain material group1; ultra low fucing porcelain (Finesse), group 2; Lithium-disilicate based all-porcelain (IPS E-Max Press), and group3; zirconia (Zirkonzahn Prettau). The specimens were randomly further divided into two groups of 36 to evaluate the effect of 2 bleaching agents%10 Opalescence treswhite supreme gel for group a and%38 Opalescence boost gel for group b. Bleaching agents were applied to porcelain surface according to manufacturer’s instructions. For surface roughness measurement a profilometer was used. The data were analyzed by one way ANOVA and paired t test (p<.05).

Results: Bleaching agents did not significantly affect the surface roughness of the group 2 and group 3 however, they significantly increased the roughness of the group 1.

Conclusions: Bleaching agents may affect the roughness of ultra low fucing restorations. Bleaching agents should not be applied to restorations (especially low fucing restorations) due to the high risk of causing surface roughness.