Amalgam (dentistry) significantly affect the structure and mechanical properties of set dental amalgam. In conventional amalgam, γ2 phase is the most reactive and readily forms an anode. It will break down releasing corrosion products and mercury. Some of the mercury will combine rapidly with unreacted alloy and some will be ingested. The chances of ditching are further increased. Copper-enriched amalgams contain little or no γ2 phase. The copper–tin phase, which replaces γ2 in these materials, is still the most corrosion-prone phase in the amalgam. The corrosion however is still much lower than conventional amalgam. In spite of that, it is thought that
Amalgam tattoo from pencil leads), and is sometimes termed a "graphite tattoo", although this is less common than tattooing with amalgam. The diagnosis is clinical. Amalgam tattoo can be distinguished from other causes of localized oral pigmentation because it does not change significantly in size or color, although it may appear to slowly enlarge for several months after the initial implantation of the metal particles. Some amalgam tattoos appear radio-opaque on radiographs (i.e. they show up on x-rays), although in many cases amalgam tattoos have no radiographic features since the responsible particle(s) of amalgam are very small even though clinically the area