title: Surface Modifications on Aesthetically Restored Teeth following Home Bleaching with 16% Peroxide Carbamide.
abstract: OBJECTIVE
  This clinical study evaluated the effects of a highly concentrated home-bleaching agent on the surface morphology of aesthetically restored teeth.
  
  
  METHODS
  Specimens of human enamel and micro-hybrid composite resin were randomly adhered to the buccal side of right premolar and molar teeth of ten volunteers, who underwent a routine home-bleaching procedure with 16% carbamide peroxide on the upper jaw for 8 days. The mandibular unbleached specimens served as paired controls (n=10). Ultra-structural assessment of the sample was carried out by scanning electron microscopy, and the resulting images were blindly evaluated for topographical alterations. The differences between groups were calculated with the Mann-Whitney test adjusted at the 95% confidence interval.
  
  
  RESULTS
  The bleached enamel presented significantly more morphological changes than the control group. The aspect of resin composite exposed to the whitening substance was statistically similar to that observed in the corresponding control group (P<.05).
  
  
  CONCLUSIONS
  The occurrence of surface topography changes during home bleaching of aesthetically restored teeth with 16% carbamide peroxide was restricted to enamel.
authors.affiliation: Department of Dentistry, Endodontics and Dental Materials, School of Dentistry, University of São Paulo, Bauru, SP, Brazil.
authors.forename: Augusto
authors.initials: A
authors.lastname: Bodanezi
authors.forename: Marcos Eugênio
authors.initials: ME
authors.lastname: de Bittencourt
authors.forename: Rafaela Vanni
authors.initials: RV
authors.lastname: Bodanezi
authors.forename: Tatiana
authors.initials: T
authors.lastname: Zottis
authors.forename: Etiene Andrade
authors.initials: EA
authors.lastname: Munhoz
authors.forename: Bruno
authors.initials: B
authors.lastname: Carlini