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Photographs of six groups under a stereomicroscope (×50): (a) unbleached group (group 1); (b) group in which the filling was done immediately after bleaching (group 2); (c) delayed filling group (group 3); (d) sodium ascorbate treated group (group 4); (e) sodium ascorbate combined with surfactant treated group (group 5); (f) catalase-treated group (group 6)
