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
Real element formula_1, Every involution is strongly real. Furthermore, every element that is the product of two involutions is strongly real. Conversely, every strongly real element is the product of two involutions. If and formula_1 is real in formula_2 and formula_30 is odd, then formula_1 is strongly real in formula_2. The extended centralizer of an element formula_1 of a group formula_2 is defined as making the extended centralizer of an element formula_1 equal to the normalizer of the set The extended centralizer of an element of a group formula_2 is always a subgroup of formula_2. For involutions or non-real elements, centralizer and