title: Randomized clinical trial on the efficacy of a new bleaching lacquer for self-application.
abstract: BACKGROUND
  This study evaluated the clinical efficacy and duration of effectiveness of a new bleaching lacquer for self-application without the use of mouth guards. It compared two different application times.
  
  
  METHODS
  Forty-six adult subjects who requested bleaching treatment were selected to participate in this randomized, single-blind (examiner-blinded), single center, two-group trial. The subjects were randomly divided into two groups (n=23 each), each being instructed to bleach (8% carbamide peroxide) their six maxillary anterior teeth for two weeks. Daily contact time in Group 1 was 20 minutes once a day and, in Group 2, the time was 20 minutes twice a day. Efficacy was measured subjectively using the Chromascop Complete shade scores obtained at baseline and after one, two and three weeks, as well as after one, three, six and nine months.
  
  
  RESULTS
  After two weeks of treatment, the teeth in the Group 1 subjects exhibited a 2.4 +/- 0.2 mean shade scores improvement compared to baseline (p < 0.001; t-test for paired samples), and the subjects' teeth in Group 2 exhibited a 3.5 +/- 0.1 mean shade scores improvement (p < 0.001). However, the difference between both groups was not statistically significant (p > 0.05). The observed effects were stable for six months.
  
  
  CONCLUSIONS
  It can be concluded that the new bleaching lacquer is efficacious; however, a double application does not seem to be obligatory.
authors.affiliation: Department of Operative Dentistry and Periodontology, University School of Dental Medicine, Campus Benjamin Franklin, Charité-Universitätsmedizin Berlin, Berlin, Germany. catharina.zantner@charite.de
authors.forename: Catharina
authors.initials: C
authors.lastname: Zantner
authors.forename: Foteini
authors.initials: F
authors.lastname: Derdilopoulou
authors.forename: Peter
authors.initials: P
authors.lastname: Martus
authors.forename: Andrej M
authors.initials: AM
authors.lastname: Kielbassa
mesh_terms: D000328:Adult; D000368:Aged; D000077463:Carbamide Peroxide; D002482:Cellulose; D003080:Cold Temperature; D003116:Color; D003481:Cuspid / Q000473:pathology; D003807:Dentin Sensitivity / Q000139:chemically induced / Q000175:diagnosis; D004338:Drug Combinations; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007180:Incisor / Q000473:pathology; D007764:Lacquer; D008297:Male; D008875:Middle Aged; D016877:Oxidants / Q000008:administration & dosage* / Q000009:adverse effects; D017060:Patient Satisfaction; D010545:Peroxides / Q000008:administration & dosage* / Q000009:adverse effects; D012646:Self Administration; D016037:Single-Blind Method; D013997:Time Factors; D014073:Tooth Bleaching / Q000009:adverse effects / Q000379:methods*; D016896:Treatment Outcome; D014508:Urea / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*
chemical_list: D004338:Drug Combinations; D016877:Oxidants; D010545:Peroxides; D000077463:Carbamide Peroxide; D014508:Urea; D002482:Cellulose