Oxidative stress induced by blue light irradiation of P. gingivalis. (A) ROS generation levels upon blue light irradiation in P. gingivalis. (n = 3) †Significant difference (p < 0.0001). (B) Generation of 8-OHdG upon blue light irradiation of P. gingivalis (n = 3) *Significant difference (p < 0.05).