Amalgam (chemistry) Amalgam (chemistry) An amalgam is an alloy of mercury with another metal, which may be a liquid, a soft paste or a solid, depending upon the proportion of mercury. These alloys are formed through metallic bonding, with the electrostatic attractive force of the conduction electrons working to bind all the positively charged metal ions together into a crystal lattice structure. Almost all metals can form amalgams with mercury, the notable exceptions being iron, platinum, tungsten, and tantalum. Silver-mercury amalgams are important in dentistry, and gold-mercury amalgam is used in the extraction of gold from ore. Zinc amalgam finds use in
Amalgam (dentistry) properties of amalgam. Creep or plastic deformation happens when subjected to intra-oral stresses such as chewing or grinding. Creep causes the amalgam to flow and protrudes from the margin of the cavity forming unsupported edges. ‘Ditch’ is formed around the margins of the amalgam restoration and make it prone to fracture. The γ2 phase of amalgam is primarily responsible for high values of creep. Corrosion occurs when an electrolytic cells of anode and cathode set up in the presence of electrolytes. The multiphase structure of dental amalgam can contribute as an anode or cathode with saliva as electrolytes. Corrosion may