Effect of Low-level Laser Therapy on Post-bleaching Sensitivity and Color Change

Received Low-lever laser therapy using the infrared spectrum, with a wavelength of 808 nm in its active medium AsGaAl (arsenic-gallium-aluminum), at two points: on the central of cervical and medial regions of incisors, canines and premolars in the corresponding hemi-arch. At each point, 60 J/cm2 was applied during 16 seconds with an irradiance of 3.75 W/cm² using the therapeutic visible infrared device.

Three 15-minute applications of 35% hydrogen peroxide gel (Whiteness HP, FGM®, Joinville, SC, Brazil) were carried out, totaling 45 minutes in each of the four bleaching sessions, with an one-week interval between applications.

The laser tip was positioned similarly to experimental group but without light irradiation