title: Clinical study of tooth shade lightening from dentist-supervised, patient-applied treatment with two 10% carbamide peroxide gels.
abstract: OBJECTIVE
  Prescribed, patient-applied tooth lightening agents, or nightguard vital bleaching, typically utilizes a 10% carbamide peroxide agent applied during nocturnal hours. The purpose of this randomized double-blind study was to compare the amount of tooth color change in two groups of subjects using dentist-supervised, patient-applied 10% carbamide peroxide gel.
  
  
  METHODS
  One group used Opalescence (Ultradent Products Inc., South Jordan, Utah) and the other NiteWhite Excel (Discus Dental, Inc., Los Angeles, California). Evaluation of tooth color for the six maxillary anterior teeth was done using a Vita shade guide at baseline, 1, 2, and 4 weeks. Subjects were instructed to apply the gel nocturnally using a custom-made soft tray 8 hours per day for 2 weeks. The 16 tabs of the shade guide were ranked according to value from darkest to lightest. The number (1-16) that correlated to the shade tab selected as the match for each tooth was the outcome variable. A Kruskal-Wallis one way analysis of variance on ranks was used.
  
  
  RESULTS
  The test revealed no statistically significant difference between Opalescence and NiteWhite Excel for lightening the teeth (p = .807). The color change was still significant after 2 weeks without further bleaching activity. The baseline evaluation of the maxillary incisors and canines for all subjects, regardless of group, demonstrated a significant shade difference, with the canines being darker. This difference was not seen after 2 weeks of active bleaching or at the 4-week evaluation.
  
  
  CONCLUSIONS
  In this study comparing bleaching products, patients using Opalescence and NiteWhite Excel experienced a significant change in the color of their teeth relative to baseline values after 2 weeks of active treatment.
authors.affiliation: Department of Oral Rehabilitation, School of Dentistry, Medical College of Georgia, Augusta, USA. rcibirka@mail.mcg.edu
authors.forename: R M
authors.initials: RM
authors.lastname: Cibirka
authors.forename: M
authors.initials: M
authors.lastname: Myers
authors.forename: M C
authors.initials: MC
authors.lastname: Downey
authors.forename: S K
authors.initials: SK
authors.lastname: Nelson
authors.forename: W D
authors.initials: WD
authors.lastname: Browning
authors.forename: I K
authors.initials: IK
authors.lastname: Hawkins
authors.forename: G L
authors.initials: GL
authors.lastname: Dickinson
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D000077463:Carbamide Peroxide; D003742:Dental Devices, Home Care; D004311:Double-Blind Method; D004338:Drug Combinations; D005260:Female; D006801:Humans; D008297:Male; D010545:Peroxides / Q000627:therapeutic use; D014073:Tooth Bleaching / Q000379:methods*; D014075:Tooth Discoloration / Q000628:therapy*; D016896:Treatment Outcome; D014508:Urea / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D004338:Drug Combinations; D010545:Peroxides; D000077463:Carbamide Peroxide; D014508:Urea