title: Effect of Pd and In on mercury evaporation from amalgams.
abstract: The amount of Hg vapor released from "synthesized" gamma 1 with 1% (wt) Pd was reported to be less than 30% of that from gamma 1 with no Pd. This study tested the hypothesis that Hg evaporation from Pd-containing amalgams decreases with Pd concentration and that In also reduces Hg vapor. Specimens (4 mm dia, 8 mm long) were prepared by triturating Ag-Sn(25%)-Cu(12%) alloy powder containing 0.5-9.0% Pd with pure Hg and by triturating 3% Pd alloy powder with Hg containing 1-5% In (all residual Hg approximately equal to 62%). The total amount (ng/mm2) of Hg vapor released at 37 degrees C from freshly prepared amalgams was measured. Pd (3-9%) in the powder significantly (p < 0.05) decreased Hg vapor release from amalgams during setting. Use of In-containing Hg also reduced Hg vapor release (5% In, p < 0.05). The reduction in the Hg vapor pressure by adding Pd and the rapid oxide film formation on the In-containing amalgam appear to work together to reduce Hg vaporization from these amalgams.
authors.affiliation: Department of Biomaterials Science, Baylor College of Dentistry, Texas A&M University System, Dallas, USA.
authors.forename: T
authors.initials: T
authors.lastname: Okabe
authors.forename: K
authors.initials: K
authors.lastname: Ohmoto
authors.forename: H
authors.initials: H
authors.lastname: Nakajima
authors.forename: M
authors.initials: M
authors.lastname: Woldu
authors.forename: J L
authors.initials: JL
authors.lastname: Ferracane
mesh_terms: D002152:Calorimetry, Differential Scanning; D003723:Dental Amalgam / Q000032:analysis / Q000737:chemistry*; D004305:Dose-Response Relationship, Drug; D007204:Indium / Q000032:analysis / Q000737:chemistry*; D008628:Mercury / Q000032:analysis / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D010165:Palladium / Q000032:analysis / Q000737:chemistry*; D011208:Powders; D013997:Time Factors; D014835:Volatilization; D014961:X-Ray Diffraction
chemical_list: D011208:Powders; D007204:Indium; D010165:Palladium; D003723:Dental Amalgam; D008628:Mercury