title: An in vivo study of the effect of a 38 percent hydrogen peroxide in-office whitening agent on enamel.
abstract: BACKGROUND
  In an in vivo study, the authors tested the hypothesis that no difference in enamel surface roughness is detectable either during or after bleaching with a high-concentration in-office whitening agent.
  
  
  METHODS
  The authors performed profilometric and scanning electron microscopic (SEM) analyses of epoxy resin replicas of the upper right incisors of 20 participants at baseline (control) and after each bleaching treatment with a 38 percent hydrogen peroxide whitening agent, applied four times, at one-week intervals. The authors used analysis of variance for repeated measures to analyze the data statistically.
  
  
  RESULTS
  The profilometric analysis of the enamel surface replicas after the in vivo bleaching protocol showed no significant difference in surface roughness parameters (P > .05) compared with those at baseline, irrespective of the time interval. Results of the correlated SEM analysis showed no relevant alteration on the enamel surface.
  
  
  CONCLUSIONS
  Results of this in vivo study support the tested hypothesis that the application of a 38 percent hydrogen peroxide in-office whitening agent does not alter enamel surface roughness, even after multiple applications.
  
  
  CONCLUSIONS
  The use of a 38 percent hydrogen peroxide in-office whitening agent induced no roughness alterations of the enamel surface, even after prolonged and repeated applications.
authors.affiliation: Division of Dental Sciences and Biomaterials, Department of Biomedicine, University of Trieste, Piazza Ospedale, 1, 34129 Trieste, Italy. m.cadenaro@fmc.units.it
authors.forename: Milena
authors.initials: M
authors.lastname: Cadenaro
authors.forename: Chiara Ottavia
authors.initials: CO
authors.lastname: Navarra
authors.forename: Annalisa
authors.initials: A
authors.lastname: Mazzoni
authors.forename: Cesare
authors.initials: C
authors.lastname: Nucci
authors.forename: Bruce A
authors.initials: BA
authors.lastname: Matis
authors.forename: Roberto
authors.initials: R
authors.lastname: Di Lenarda
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Breschi
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D003743:Dental Enamel / Q000187:drug effects* / Q000648:ultrastructure; D005260:Female; D006801:Humans; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D007180:Incisor; D008297:Male; D008437:Maxilla; D008855:Microscopy, Electron, Scanning; D016877:Oxidants / Q000494:pharmacology*; D016628:Replica Techniques; D013499:Surface Properties / Q000187:drug effects; D014073:Tooth Bleaching / Q000379:methods; D055815:Young Adult
chemical_list: D016877:Oxidants; D006861:Hydrogen Peroxide