ASTRALLOY is a non gamma 2, spherical, single composition dental silver amalgam alloy for dental restorations. It is characterized by its need for 23% less mercury than the common 1:1 ratio when amalgamated. It does not contain zinc and therefore problems that are associated with moisture during the restoration process are eliminated. The alloy consists of spherical and irregular shaped spheroidal particles which ensure excellent condensability. This gives high marginal adaptation and marginal seal thus avoiding post operative sensitivity.
Silver (Ag) 60%, Tin (Sn) 28%, Copper (Cu) 12%
Ratio – Alloy : Hg = 1 : 0.78
Characteristics - Advantages
23% less mercury
High resistance to corrosion
Very good marginal adaptation
High resistance to wear
Compressive strength 1 hour (MPa) - 220
Compressive strength 24 hour (MPa) - 440
Static creep (%) - 0.11
Dimensional change (%) - 0.015
Working time - 4'30"- 5'00"
Trituration time - Silamat mixer - 10"