Effect of Home Bleaching on Surface Roughness of Novel Composite Resins Subjected to One Step Polishing System: An In Vitro Study

Abstract

The aims of this in vitro study was to evaluate surface roughness (Ra) of fourcontemporary composite resin materials after applying home bleaching agent.Materials and Methods: Forty-eight composite specimens were made from fourgroups of different types composite resins (one-submicron hybrid, onemicrohybrid and two nanohybrid) of 12 specimens each: Group 1: BrilliantEverGlow, group 2: G-ænial from GC, group 3: Evetric and group 4: Ice, SDI. Allthe samples were polished with one step polishing system OptraPol. Each groupwas further subdivided into two subgroups (A&B) (n=6). Subgroups A werestored in distilled water as control, while subgroups B were bleached with 20%carbamide peroxide home bleaching agent for 14 day. Surface roughness analysiswas then performed for all the samples using atomic force microscopy (AFM).Results were statistically analyzed using One-way ANOVA/LSD test analyzingthe differences between the subgroups at p<0.05.Results: Surface roughness of all the groups increased after bleaching; however, LSDtest showed significant differences that were only recorded between the subgroupsof groups 3 & 4.Conclusion: 20% at-home bleaching treatment significantly affected surfaceroughness of both nanohybrid composite groups, while, it did not produce asignificant surface changes for microhybrid and submicron composite resin