Shin 2010.

Methods	Title: the evaluation of clinical efficacy and longevity of home bleaching without combined application of in‐office bleaching Trial design: randomised controlled trial Location: not reported Language: Korean Number of centres: 1 Recruitment period: not reported Funding source: not reported
Participants	Participants: age 19 to 40 years Total number: 28 Inclusion criteria: mild tooth discolouration; 6 anterior teeth present Exclusion criteria: resin filling; porcelain restoration; dental caries; gingivitis and periodontitis Number randomised: not reported Method of randomisation: not reported Method of allocation concealment: not reported Method of blinding: not reported Number evaluated: not reported
Interventions	Total number of intervention groups: 2 15% carbamide peroxide tray Placebo Duration of treatment: 4 weeks
Outcomes	Change in tooth colour: b (decreased b* indicates reduced yellowness); ΔL* (increased ΔL* is increased brightness)
Notes	Sample size calculation: not reported Adverse effects: not reported Health‐related quality of life: not reported Key conclusions of the study authors: "Stronger colour change was observed for overall teeth samples in experimental group immediately after treatment (at 4 weeks) compared to ones in control group. There was also a significant difference between baseline and 8 weeks or 12 weeks as the tooth got darker with time) Correspondence required: yes: missing data, number of participants in control and experimental groups not reported. Authors have been mailed requesting for the data Contact: Sung Wun Yang, dentyun@catholic.ac.kr