title: Comparison of two at-home whitening products of similar peroxide concentration and different delivery methods.
abstract: OBJECTIVE
  This study compared the whitening efficacy, side effects, and patients' preferences/perceptions of two whitening systems of similar peroxide concentration but different formulation and delivery methods.
  
  
  METHODS
  The tooth color change of 24 participants was measured using a shade guide (BSG) and a spectrophotometer (ES). Color difference was calculated: ΔE* = [(ΔL*)(2) + (Δa*)(2) + (Δb*)(2)](1/2). One whitening treatment was randomly applied to the right or left maxillary anterior teeth and the other was applied to the contralateral teeth, at-home with 35% carbamide peroxide in a tray (TW) or with 14% hydrogen peroxide in strips (WS). The tooth color was evaluated at baseline, 15 and 30 days (15 days postwhitening). Participants rated their tooth and soft tissue sensitivity (1-10 scale) and completed a questionnaire on their preferences. Results were analyzed by repeated measurement regression analysis/Tukey and Mann-Whitney (p<0.05).
  
  
  RESULTS
  At 15 days, the teeth treated with TW and WS presented ΔE* = 7 and 6, respectively (ΔBSG=3 for both), and at 30 days, they presented ΔE* = 7.5 and 6.5, respectively (ΔBSG=3 for both). There was no significant difference in tooth and soft tissue sensitivity between treatments. No participant reported tooth and gingival sensitivity at the postwhitening appointment. Of the participants, 83% preferred the TW over WS.
  
  
  CONCLUSIONS
  Both ΔE* and ΔBSG showed no significant difference in tooth color change between TW and SW at either time point. By the end of the study no participants reported tooth and gingival sensitivity. Participants preferred TW over SW.
authors.affiliation: Department of Restorative Dentistry, Oregon Health & Science University, Portland, OR, USA. dacostaj@ohsu.edu
authors.forename: J B
authors.initials: JB
authors.lastname: da Costa
authors.forename: R
authors.initials: R
authors.lastname: McPharlin
authors.forename: T
authors.initials: T
authors.lastname: Hilton
authors.forename: J I
authors.initials: JI
authors.lastname: Ferracane
authors.forename: M
authors.initials: M
authors.lastname: Wang
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000368:Aged; D001294:Attitude to Health; D000077463:Carbamide Peroxide; D003116:Color; D003807:Dentin Sensitivity / Q000209:etiology; D005260:Female; D005500:Follow-Up Studies; D005881:Gingiva / Q000187:drug effects; D006801:Humans; D006861:Hydrogen Peroxide / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D057240:Patient Preference; D010545:Peroxides / Q000008:administration & dosage* / Q000009:adverse effects; D016037:Single-Blind Method; D013053:Spectrophotometry; D014070:Tooth / Q000473:pathology; D014073:Tooth Bleaching / Q000379:methods* / Q000523:psychology; D058205:Tooth Bleaching Agents / Q000008:administration & dosage* / Q000009:adverse effects; D016896:Treatment Outcome; D014508:Urea / Q000008:administration & dosage / Q000009:adverse effects / Q000031:analogs & derivatives*; D055815:Young Adult
chemical_list: D010545:Peroxides; D058205:Tooth Bleaching Agents; D000077463:Carbamide Peroxide; D014508:Urea; D006861:Hydrogen Peroxide