title: In-use peroxide kinetics of 10% hydrogen peroxide whitening strips.
abstract: OBJECTIVE
  Clinical research was conducted to establish the peroxide degradation profile of a very thin 10% hydrogen peroxide bleaching gel delivered on a flexible polyethylene strip.
  
  
  METHODS
  Sixteen subjects participated in this study of Crest Whitestrips Premium, a thin layer of 10% hydrogen peroxide gel. Application was supervised, and strips were removed after five, 10, 30, and 60 minutes. Samples were collected from the strips, teeth, gingiva, and saliva, and peroxide levels were derived using a colorimetric peroxide assay.
  
  
  RESULTS
  At five minutes, median peroxide concentrations were 7.3%, 6.4%, and 0.7% for strips, teeth, and gingiva, respectively, declining to 4.6%, 2.9%, and 0.1% at 30 minutes. Salivary samples never exceeded a median concentration of 0.014% at any time point. Samples differed significantly (p < 0.01) with respect to the 30- and 60-minute area-under-the-curve calculations, with the highest concentrations on the strip and teeth, and the lowest on the gingiva and in saliva. Median peroxide concentrations on strips and teeth remained above 2% over 60 minutes. At all post-treatment time points, the gingival peroxide concentration was an order of magnitude lower than the teeth samples.
  
  
  CONCLUSIONS
  Use of 10% hydrogen peroxide whitening strips yielded appreciable peroxide on teeth over a 60-minute period, with rapid peroxide degradation on the gingiva, and exceedingly low accumulation in saliva anytime during use.
authors.affiliation: The Procter & Gamble Company Mason, OH, USA. gerlach.rw@pg.com
authors.forename: Robert W
authors.initials: RW
authors.lastname: Gerlach
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Barker
authors.forename: Paul A
authors.initials: PA
authors.lastname: Sagel
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Ralston
authors.forename: Donna A
authors.initials: DA
authors.lastname: McMillan