Changes in oral health related quality of life after dental bleaching in a double-blind randomized clinical trial

Abstract

Objectives: This study aimed to assess changes in oral health-related quality of life (OHRQoL) in individuals enroled in a double-blind randomized clinical trial conducted to evaluate the efficacy and safety of two carbamide peroxide concentrations used in at-home vital bleaching in the city of Pelotas, Southern Brazil.

Methods: Ninety-two volunteers with a shade mean of C1 or darker for the six maxillary anterior teeth were randomized into two balanced groups (n=46) according to bleaching agent concentration: 10% or 16% carbamide peroxide. The patients were instructed to use the whitening agent in a tray for 2h once a day for three weeks. To assess changes in OHRQoL, participants completed the oral impact on daily performance (OIDP) at the start and one week after the completion of treatment. Because there was no difference with regard to whitening effect or tooth sensitivity during or after treatment the two groups were merged for the analyses of the current article. Before-and-after changes in OIDP scores were assessed by chi-square and McNemar tests (p<0.05).

Results: Mean pre- and post-treatment OIDP scores varied from 0.42 to 0.60. When the frequency of impacts for different activities were compared, there was an increase in difficulty in cleaning teeth (p=0.02) and a significant reduction in smiling and showing teeth with embarrassment (p=0.03). Regarding the symptoms and main oral conditions that generated impact, there was higher number of participants reporting pain (p=0.05) after treatment. In opposite, significant decrease was observed in individuals reporting being unhappy with their appearance (p=0.03). On the contrary, it was showed a decrease in impacts resulting from dental colour was observed after bleaching (p=0.03).

Conclusion: Quality of life is complex and encompasses different domains. Although positive impact of the dental bleaching was detected, with patients showing more their teeth without embarrassment, difficult in dental hygiene and pain resulting from the treatment were also reported, and this can negatively impact daily performances. Dentists must consider these aspects when performing aesthetics procedures.

Keywords: Oral health; Quality of life; Randomized controlled trial; Tooth bleaching.