Michael George Botelho1, Alex Wai Kwok Chan2, Philip Richard Holmes Newsome2, Colman Patrick McGrath3, Walter Yu Hang Lam4. 1. Prosthodontics, Faculty of Dentistry, The University of Hong Kong, Prince Philip Dental Hospital, Sai Ying Pun, Hong Kong. Electronic address: botelho@hku.hk. 2. Private Practise, Hong Kong, China. 3. Dental Public Health, Faculty of Dentistry, The University of Hong Kong, Prince Philip Dental Hospital, Sai Ying Pun, Hong Kong. 4. Prosthodontics, Faculty of Dentistry, The University of Hong Kong, Prince Philip Dental Hospital, Sai Ying Pun, Hong Kong.
Abstract
OBJECTIVES: To investigate the effectiveness of two home bleaching modalities on whitening of tetracycline-stained teeth (TST). METHODS: A randomized controlled trial on the bleaching effect of 15% carbamide peroxide gel loaded in tray and 6.5% hydrogen peroxide strip in subjects with TST was performed. Eligible subjects were judged independently by two assessors, and randomly assigned into the tray or the strip group. Lightness (L*), redness (a*) and yellowness (b*) were measured with colorimeter at baseline, one, two and three months. Any adverse reaction associated with bleaching were also recorded. Overall colour changes (ΔE) were analysed by one-sample and independent t-test/Wilcoxon test at significance level α=0.05. RESULT: Twelve and fourteen participants were allocated to the tray and the strip group respectively. Both groups experienced noticeable and significant L*a*b* improvement at the end of the trial in comparison to the baseline (p<0.05). Significant improvement was observed in the first month for the tray group (p<0.05) and in the first two months for the strip group (p<0.05). While greater lightness improvement was observed in the tray group over the strip group in the first month (p=0.02), the reverse was noticed in the second month (p=0.01). There was no difference between two groups at the end of this trial (p<0.05) and no significant adverse reactions were observed. CONCLUSION: Over a three-month period, 6.0% hydrogen peroxide strip performed equally well as the 15% carbamide peroxide tray delivery system in TST. CLINICAL SIGNIFICANCE: Home bleaching systems produce noticeable tooth whitening effect in subjects with tetracycline-stained teeth.
RCT Entities:
OBJECTIVES: To investigate the effectiveness of two home bleaching modalities on whitening of tetracycline-stained teeth (TST). METHODS: A randomized controlled trial on the bleaching effect of 15% carbamide peroxide gel loaded in tray and 6.5% hydrogen peroxide strip in subjects with TST was performed. Eligible subjects were judged independently by two assessors, and randomly assigned into the tray or the strip group. Lightness (L*), redness (a*) and yellowness (b*) were measured with colorimeter at baseline, one, two and three months. Any adverse reaction associated with bleaching were also recorded. Overall colour changes (ΔE) were analysed by one-sample and independent t-test/Wilcoxon test at significance level α=0.05. RESULT: Twelve and fourteen participants were allocated to the tray and the strip group respectively. Both groups experienced noticeable and significant L*a*b* improvement at the end of the trial in comparison to the baseline (p<0.05). Significant improvement was observed in the first month for the tray group (p<0.05) and in the first two months for the strip group (p<0.05). While greater lightness improvement was observed in the tray group over the strip group in the first month (p=0.02), the reverse was noticed in the second month (p=0.01). There was no difference between two groups at the end of this trial (p<0.05) and no significant adverse reactions were observed. CONCLUSION: Over a three-month period, 6.0% hydrogen peroxide strip performed equally well as the 15% carbamide peroxide tray delivery system in TST. CLINICAL SIGNIFICANCE: Home bleaching systems produce noticeable tooth whitening effect in subjects with tetracycline-stained teeth.