Evaluation of tooth color, whiteness changes and sensitivity following laser-assisted in-office tooth bleaching using Er,Cr:YSGG laser: A prospective clinical study.

Purpose: This prospective clinical study evaluated the tooth color (ΔΕ*ab and ΔΕ₀₀) and whiteness (ΔWID) changes, as well as tooth sensitivity (TS) induced after performing in-office tooth bleaching with or without light-activation of the bleaching gel using Er,Cr:YSGG laser irradiation.

Methods: 20 subjects were enrolled for the study. The bleaching session was conducted with two 20-minute sessions of a 40% hydrogen peroxide bleaching agent assisted by Er,Cr:YSGG laser (2,780 nm) at the left hemiarch and without laser activation on the right hemiarch. ΔΕ*ab, ΔΕ₀₀ and ΔWID were evaluated in central incisors and canines using a clinical spectrophotometer immediately, 7 days and 30 days after the bleaching procedure. TS was evaluated during the bleaching treatments in both hemiarches of the patients using a visual analogue scale.

Results: The results revealed a significant increase in tooth color and whiteness changes following the tooth bleaching in both laser-treated and conventional groups and in all teeth. Tooth color and whiteness changes were observed immediately after the different treatments and were gradually reduced after 7 and 30 days (P< 0.05). Between the conventional and laser-assisted technique, there were statistically significant differences only in canines (P< 0.05) and in lower central incisors (P< 0.05). Mild TS was noticed in 85% of the patients, without differences between the bleaching treatments (P> 0.05).

Clinical significance: Er,Cr:YSGG laser-assisted tooth bleaching treatment may enhance tooth color and whiteness changes but not in all the examined tooth types, without inducing more intense tooth sensitivity compared to the conventional technique.