Zhao K, Zong L, Zhang Q, Att W
Quintessence Int 2013;44(8):601-7
OBJECTIVE: The aim of this clinical study was to compare tooth shade, color rebound, and tooth sensitivity after using either a combined bleaching technique (CBT) or a deep bleaching technique (DBT) to lighten stained teeth. CBT is a two-stage bleaching process consisting of an initial in-office bleaching treatment session using 35% hydrogen peroxide (HP) followed by a 7-day at-home bleaching session with 6% HP. DBT involves a 7-day at-home bleaching session with 6% HP prior to the initiation of a two-stage CBT process.
METHOD AND MATERIALS: Thirty-six volunteers were recruited in this split-mouth design randomized clinical trial. Tooth shade was objectively evaluated by using a spectrophotom-eter and shade guide tabs. Tooth and gingival tissue sensitivity were self-evaluated by recording any tooth or gingival sensitivity on a daily basis.
RESULTS: Both CBT and DBT presented satisfactory whitening effects. Although DBT resulted in a better shade change, the two bleaching techniques had a similar rebound effect. CBT was associated with a lower frequency of tooth sensitivity, but both bleaching techniques can be considered safe from a clinical standpoint.
CONCLUSION: The results indicate that CBT might potentially be preferred to whiten teeth, thus promoting the shade change, and avoiding gingival and tooth sensitivity.