title: The effect of hydrogen peroxide concentration on metal ion release from dental amalgam.
abstract: OBJECTIVE
  The aim of this study was to investigate the effect of hydrogen peroxide (HP) concentration on metal ion release from dental amalgam.
  
  
  METHODS
  Dental amalgam discs (n=25) were prepared by packing amalgam into cylindrical plastic moulds (10 mm diameter and 2 mm height). The discs were divided into five equal groups and each group was immersed in 20 ml of either 0%, 1%, 3%, 10% or 30% HP solution for 24 h at 37 degrees C. Samples were taken for metal ion release determination (Hg, Ag, Sn and Cu) using inductively coupled plasma mass spectrometry (ICP-MS). The surface roughness of each disc was measured before and after bleaching.
  
  
  RESULTS
  The differences in concentration of metal ions released after treatment with 0% (control) and each of 1%, 3%, 10% and 30% HP were statistically significant (p<0.05). Metal ion release for the elements (Hg, Ag, Sn and Cu) increased with exposure to increasing concentrations of HP. Surface roughness measurements of the samples before and after treatments with HP solutions were not significantly different (p>0.05).
  
  
  CONCLUSIONS
  Exposure to HP bleaching agent was associated with increased metal ion released from dental amalgams compared to treatment with a control solution. Ion release was in proportion to the peroxide concentration tested, with the highest concentration associated with the greatest metal ion release for all elements investigated.
authors.affiliation: Centre for Biomaterials & Tissue Engineering, Department of Adult Dental Care, School of Clinical Dentistry, University of Sheffield, Claremont Crescent, Sheffield S10 2TA, UK. s.k.al-salehi@sheffield.ac.uk
authors.forename: S K
authors.initials: SK
authors.lastname: Al-Salehi
authors.forename: P V
authors.initials: PV
authors.lastname: Hatton
authors.forename: C W
authors.initials: CW
authors.lastname: McLeod
authors.forename: A G
authors.initials: AG
authors.lastname: Cox
mesh_terms: D003300:Copper / Q000737:chemistry; D003722:Dental Alloys / Q000737:chemistry; D003723:Dental Amalgam / Q000737:chemistry*; D006801:Humans; D006861:Hydrogen Peroxide / Q000008:administration & dosage / Q000737:chemistry*; D007477:Ions; D013058:Mass Spectrometry; D008422:Materials Testing; D008628:Mercury / Q000737:chemistry; D008670:Metals / Q000737:chemistry*; D016877:Oxidants / Q000008:administration & dosage / Q000737:chemistry*; D012834:Silver / Q000737:chemistry; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014001:Tin / Q000737:chemistry
chemical_list: D003722:Dental Alloys; D007477:Ions; D008670:Metals; D016877:Oxidants; D012834:Silver; C036886:tytin; D014001:Tin; D003300:Copper; D003723:Dental Amalgam; D006861:Hydrogen Peroxide; D008628:Mercury