Main

do Amaral Gonzaga de Almeida LC, Riehl H et al. Int J Periodont Restor Dent 2012; 32: 303–309

This study did not find that the use of high concentration bleaching agents (35% hydrogen peroxide) with or without the use of light sources, conferred superior whitening of teeth compared with at-home bleaching with 10% carbamide peroxide. The in-office technique was carried out over three appointments for 90 minutes in total, in combination with lights sources. The at-home regimen consisted of using bleaching trays, for three hours each day, for three weeks. The tooth colour was evaluated by comparison with a VITA shade guide. The shades were recorded once before bleaching and then on four other occasions, the last being six months after bleaching. There was no 'colour rebound' which is considered a particular problem with in-office bleaching.