title: Desensitizing agent efficacy during whitening in an at-risk population.
abstract: BACKGROUND
  Nightguard vital bleaching (NGVB) has gained acceptance among dentists and patients as a simple and effective procedure to lighten discolored teeth. Although the efficacy and predictability of NGVB have been well established, it has been documented that patients undergoing the procedure may experience side effects such as tooth sensitivity (TS) and gingival irritation (GI). A previous NGVB study suggested that selected participants might benefit from a regimen of a desensitizing agent (DSA) to decrease or prevent TS during whitening.
  
  
  OBJECTIVE
  The purpose of this study was to determine whether the daily use of an active DSA (UltraEZ, Ultradent Products Inc., South Jordan, UT, USA) during NGVB would decrease TS in a population at risk for TS when compared with a placebo.
  
  
  METHODS
  Forty subjects participated in this single-blind randomized clinical trial. All participants had indicated that they had preexisting TS or other risk factors for TS during NGVB. To evaluate TS caused by the tray alone, participants wore custom-fitted maxillary whitening trays containing no DSA or whitening solution during week 1. Next, participants were randomly assigned to apply either the active DSA or placebo daily for 14 days in the trays for 30 minutes prior to whitening. The placebo was the same formulation as UltraEZ but without the desensitizing agents (3% potassium nitrate and 0.11% by weight fluoride ion). The bleaching solution was a 10% carbamide peroxide whitening solution (Opalescence, Ultradent Inc.). Post treatment, participants were followed up for 1 week, during which time they used neither trays nor solutions. Throughout the study, participants completed a daily diary to record their perceptions of TS and the time spent wearing the tray with the whitening solution.
  
  
  RESULTS
  Forty-one percent of the active group had at least 1 day of TS during treatment compared with 78% of the placebo group. The difference was statistically significant (p = .027) using the two-tailed Fisher exact test.
  
  
  CONCLUSIONS
  This study suggests that the use of an active 3% potassium nitrate and 0.11% fluoride desensitizing agent for 30 minutes prior to whitening may decrease tooth sensitivity when compared with a placebo in a population at risk for tooth sensitivity.
authors.affiliation: Department of Diagnostic Sciences and General Dentistry, University of North Carolina School of Dentistry, Chapel Hill, NC 27599-7450, USA. ralph_leonard@dentistry.unc.edu
authors.forename: Ralph H
authors.initials: RH
authors.lastname: Leonard
authors.forename: Lynn R
authors.initials: LR
authors.lastname: Smith
authors.forename: Glenn E
authors.initials: GE
authors.lastname: Garland
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Caplan
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000077463:Carbamide Peroxide; D003807:Dentin Sensitivity / Q000139:chemically induced / Q000517:prevention & control*; D004338:Drug Combinations; D004359:Drug Therapy, Combination; D005260:Female; D005459:Fluorides / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D008437:Maxilla; D008875:Middle Aged; D009566:Nitrates / Q000008:administration & dosage*; D010545:Peroxides / Q000009:adverse effects*; D017680:Potassium Compounds / Q000008:administration & dosage*; D016037:Single-Blind Method; D014073:Tooth Bleaching / Q000009:adverse effects*; D016896:Treatment Outcome; D014508:Urea / Q000009:adverse effects* / Q000031:analogs & derivatives*
chemical_list: D004338:Drug Combinations; D009566:Nitrates; D010545:Peroxides; D017680:Potassium Compounds; C489164:UltraEZ; D000077463:Carbamide Peroxide; D014508:Urea; D005459:Fluorides; C023844:potassium nitrate