| Objectives: Considering the increasing use of vital bleaching procedures and the
increased application of newly introduced resin-based materials for tooth
restoration, this study was designed to evaluate the effect of 15% carbamide
peroxide gel on the flexural strength of three resin-based restorative materials.
Materials and Methods: Three different types of restorative materials namely
Beautifil II giomer, Cention N, and Z250 micro-hybrid composite resin were
evaluated in this in vitro, experimental study. Twenty-four bar-shaped specimens
were prepared from each restorative material, totaling 72 specimens, and were
randomly assigned to two subgroups with and without bleaching procedure (n=12).
In the bleaching subgroups, 15% carbamide peroxide gel was applied on the
specimen surface 8 h a day for 14 days. The flexural strength of the specimens was
then measured. Two-way ANOVA was used to compare the flexural strength of the
specimens.
Results: There was a significant reduction in the flexural strength of materials
following exposure to the bleaching agent (P<0.05). The flexural strength was
significantly higher in the groups that did not undergo bleaching. However, the mean
flexural strength of the restorative materials was not significantly different (P=0.12).
Conclusion: The flexural strength of Beautifil II giomer, Cention N, and Z250 microhybrid composite resin could be compromised subsequent to bleaching with 15%
carbamide peroxide gel. The three resin-based restorative materials exhibited
similar flexural strength values irrespective of the use or no use of 15% carbamide
peroxide gel. |