title: Effects of in-office and home bleaching gels on the surface mercury levels of dental amalgam.
abstract: OBJECTIVE
  The aim of this study was to evaluate the effect of different in-office and home bleaching gels on the surface mercury levels of dental amalgam.
  
  
  METHODS
  Sixty disk-shaped amalgam specimens (GS-80, SDI- Australia) were prepared and randomly divided into the following treatment groups: 1. Distilled water (control); 2. 15% home-bleach carbamide peroxide (Opalescence PF, Ultra dent, USA) applied for 6 h/day for 3 weeks; and 3. 35% in-office bleach carbamide peroxide (Opalescence Quick, Ultradent) applied for 30 min/week for 3 weeks. Levels of mercury were measured as weight percentages using an energy dispersive x-ray micro-analyzer detector connected to an electron microscope. Data was analyzed using one-way ANOVA and a post hoc Tukey tests (P<.05).
  
  
  RESULTS
  There were no significant differences between the surface mercury levels measured following treatment with the tested home-bleach and in-office bleach products (P=0.71). However, both materials yielded significantly more mercury levels than that of the control group (P<.001).
  
  
  CONCLUSIONS
  The tested bleaching products significantly elevated the surface mercury levels of amalgam in vitro.
authors.affiliation: Associate Professor, Department of Operative Dentistry, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Parnian Alizadeh
authors.initials: PA
authors.lastname: Oskoee
authors.forename: Mahdi Abed
authors.initials: MA
authors.lastname: Kahnamoui
authors.forename: Siavash Savadi
authors.initials: SS
authors.lastname: Oskoee
authors.forename: Firooz
authors.initials: F
authors.lastname: Zadfattah
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Pournaghi-Azar