Clinical Comparison of LED- and Diode Laser-activated Bleaching

To clinically compare the effects of LED- or Diode laser-activated bleaching on colour change, tooth-sensitivity, gingival-irritation and temperature variation over 9-months. Thirty-five patients with tooth colour A2 or higher will be included in the study. In a split-mouth design, using a 35% HP bleaching agent (Whiteness HP); one side of each mouth will be randomly activated by a diode laser (Epic X) and the other side by an LED (Radii Plus) light-source. During bleaching, the temperature variations will be recorded using a thermocouple from the buccal surface of canine teeth. Colour change (ΔSGU, ΔE) will be evaluated by subjective (Vita classic/bleached guide) and objective methods (spectrophotometry) before treatment and immediately, 48h, 1 week, 1, 6, 9 months after. Tooth-sensitivity and gingival- irritation will be assessed by visual analogue scale (VAS) and Gingival Index.