In both shades tested, whitening of the stained specimens was greater with Beyond and LumaWhite-Plus. This may suggest that light-activated bleaching had a greater whitening effect on stained composite. Generally, the mechanism of color change in resin composite when exposed to vital bleaching regimes includes oxidation of surface pigments, oxidation of amine compounds (which are responsible for color stability over time), or breakdown of poorly polymerized resin matrix.14 These effects could have been enhanced by the use of light-activation during the bleaching. However, the benefit of using light-activated bleaching on tooth structure has been widely debated.29–31 Therefore, it may be concluded that the use of light might be more beneficial in bleaching restorative resins than tooth structure.