Influence of the conditioned medium of orthodontic bands on the expression of antioxidant genes in human gingival fibroblasts. Gingival fibroblasts were exposed to the conditioned media of the Dentsply-Sirona (DenSir), Dentaurum (Dentaur), TP Orthodontics (TP), and Morelli bands or to the culture medium (control) for 24 hours, and the expression of PRDX1, SOD1, and GPX1 was assessed by quantitative polymerase chain reaction. The data represent means and standard deviations. Different letters indicate statistically significant differences (P < 5%) among the control and conditioned media from the bands.