title: Effects of Bleaching Agents Combined with Regular and Whitening Toothpastes on Surface Roughness and Mineral Content of Enamel.
abstract: OBJECTIVE
  The purpose of this study was to evaluate surface roughness and changes in the composition of enamel submitted to different bleaching protocols and toothbrushing with regular and whitening toothpastes.
  
  
  BACKGROUND
  Bleaching treatment could promote morphological and chemical changes in enamel surface.
  
  
  METHODS
  Enamel blocks were randomized into nine groups (n=10) according to the bleaching treatment (no bleaching, control group; 6% hydrogen peroxide, HP; or 10% carbamide peroxide, CP) and toothpaste used (placebo, PL; regular, R; or whitening dentifrice, W). Bleaching was performed according to manufacturers' instructions and all groups were submitted to 30,000 cycles of simulated toothbrushing with toothpaste (PL, R, or W). Mineral content evaluation and enamel roughness were evaluated initially (T1), after bleaching (T2), and after toothbrushing (T3), using an energy-dispersive micro X-ray fluorescence spectrometer and profilometry, respectively. Data were statistically analyzed with two way ANOVA, Tukey, and Dunnett tests (5%).
  
  
  RESULTS
  Enamel surface roughness was influenced by bleaching and toothbrushing. Surface roughness increased for the groups that brushed with the placebo dentifrice (CP+PL, HP+PL, C+PL) and for the control group that brushed with whitening dentifrice (C+W). Enamel Ca/P ratio decreased after bleaching, but toothbrushing, regardless of the dentifrice used, did not reduce the enamel mineral content.
  
  
  CONCLUSIONS
  The bleaching treatment resulted in a decrease of enamel mineral content, but the studied dentifrices did not contribute to surface mineral loss.
authors.affiliation: 1 Department of Restorative Dentistry, University of Taubaté , Taubaté, SP, Brazil .
authors.forename: Mariana Lerner
authors.initials: ML
authors.lastname: Attia
authors.affiliation: 1 Department of Restorative Dentistry, University of Taubaté , Taubaté, SP, Brazil .
authors.forename: Vanessa
authors.initials: V
authors.lastname: Cavalli
authors.affiliation: 2 Department of Mathematical and Earth Sciences, Federal University of São Paulo , Diadema, SP, Brazil .
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: do Espírito Santo
authors.affiliation: 3 Research and Development Institute (IP&D), University of Paraiba Valley, São José dos Campos, SP, Brazil .
authors.forename: Airton Abrahão
authors.initials: AA
authors.lastname: Martin
authors.affiliation: 1 Department of Restorative Dentistry, University of Taubaté , Taubaté, SP, Brazil .
authors.forename: Maria Beatriz Freitas
authors.initials: MB
authors.lastname: D'Arce
authors.affiliation: 4 Department of Restorative Dentistry, Piracicaba Dental School/ University of Campinas , Piracicaba, SP, Brazil .
authors.forename: Flávio Henrique Baggio
authors.initials: FH
authors.lastname: Aguiar
authors.affiliation: 4 Department of Restorative Dentistry, Piracicaba Dental School/ University of Campinas , Piracicaba, SP, Brazil .
authors.forename: José Roberto
authors.initials: JR
authors.lastname: Lovadino
authors.affiliation: 1 Department of Restorative Dentistry, University of Taubaté , Taubaté, SP, Brazil .
authors.forename: Marcos Augusto
authors.initials: MA
authors.lastname: do Rego
authors.affiliation: 5 Area of Restorative Dentistry, School of Dentistry, School of Medicine and Public Health of Bahia and School of Dentistry, Federal University of Bahia , Salvador, BA, Brazil .
authors.forename: Andréa Nóbrega
authors.initials: AN
authors.lastname: Cavalcanti
authors.affiliation: 1 Department of Restorative Dentistry, University of Taubaté , Taubaté, SP, Brazil .|4 Department of Restorative Dentistry, Piracicaba Dental School/ University of Campinas , Piracicaba, SP, Brazil .
authors.forename: Priscila Christiane Suzy
authors.initials: PC
authors.lastname: Liporoni
mesh_terms: D003743:Dental Enamel / Q000187:drug effects* / Q000528:radiation effects*; D003802:Dentifrices / Q000494:pharmacology*; D006801:Humans; D028022:Low-Level Light Therapy; D013499:Surface Properties / Q000187:drug effects / Q000528:radiation effects; D046509:Tissue Culture Techniques; D014073:Tooth Bleaching; D058205:Tooth Bleaching Agents / Q000494:pharmacology*; D014074:Tooth Calcification / Q000187:drug effects / Q000528:radiation effects; D014099:Toothbrushing
chemical_list: D003802:Dentifrices; D058205:Tooth Bleaching Agents