A clinical evaluation of carbamide peroxide and hydrogen peroxide whitening agents during daytime use

J Am Dent Assoc. 2000 Sep;131(9):1269-77. doi: 10.14219/jada.archive.2000.0380.


Background: Vital tooth bleaching for esthetic reasons has gained in popularity during the last few years. However, few studies have investigated the efficacy of daytime bleaching products. The purpose of this double-blind in vivo study was to evaluate the efficacy of 20 percent carbamide peroxide, or CP, and 7.5 percent hydrogen peroxide, or HP, during daytime use. The degree of color change, any color relapse, and tooth or gingival sensitivity were evaluated.

Methods: Twenty-four patients participated in this study. The bleaching gels were randomly applied to the right and left maxillary anterior teeth. Patients were shown how to place the two bleaching agents in a custom tray for one hour, twice a day for two weeks. Patients returned in one, two, three, six and 12 weeks for color evaluation with the colorimeter and shade guides as well as to have color slide photographs taken. The authors evaluated sensitivity by asking the patients to record daily for 21 days any tooth or gingival sensitivity they experienced.

Results: Use of the 20 percent CP resulted in significantly more lightness than the 7.5 percent HP during the first 14 days of the study, but at the end of the study, there was no significant difference between products with regard to tooth lightness. In addition, the authors found no statistically significant difference between products with regard to gingival or tooth sensitivity.

Conclusions: Both CP and HP are effective at-home bleaching agents when daytime bleaching is preferred.

Clinical implications: Dentists who choose to use daytime bleaching can select either CP or HP.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Carbamide Peroxide
  • Color / standards
  • Colorimetry
  • Dental Devices, Home Care*
  • Dentin Sensitivity / chemically induced
  • Double-Blind Method
  • Drug Combinations
  • Gingival Diseases / chemically induced
  • Humans
  • Hydrogen Peroxide / administration & dosage*
  • Middle Aged
  • Peroxides / administration & dosage*
  • Tooth Bleaching / adverse effects
  • Tooth Bleaching / methods*
  • Urea / administration & dosage
  • Urea / analogs & derivatives*


  • Drug Combinations
  • Peroxides
  • Carbamide Peroxide
  • Urea
  • Hydrogen Peroxide