No abstract

Purpose: This study recorded in vitro color change of three tooth bleaching techniques that included laser‐activated hydrogen peroxide and two concentrations of carbamide peroxide. Materials and Methods: Forty extracted human central incisors were exposed to argon laser‐activated 35% H2O2, 10% carbamide peroxide, or 20% carbamide peroxide. A fourth group (control) did not receive any bleach treatment (n = 10/group). Commission International de ľEclariage (CIE) L*a*b* coordinates were recorded prior to bleaching (baseline), at 1 week, and at 2 weeks. The color difference (ΔE*ab) between baseline and subsequent measurents was calculated. Results: The control group did not demonstrate significant color difference over time (p > .05). The laser group was not statistically different from the control group (p > .01). The color difference of the 10% and 20% carbamide peroxide groups was statistically different from the control group (p < .01).