High Noble Medium gold-palladium-low. Metro solders well and does not exhibit the brittleness some technicians report in other medium-gold ceramic alloys. The small quantity of silver in Metro adjusts its thermal expansion coefficient to make it much more compatible with higher expansion porcelains than other alloys in its class. Yet, it is less expensive than other alloys in this category.
A material composed primarily of noble metals [e.g., gold (Au), palladium (Pd), platinum (Pt), or silver (Ag)] intended for use in the fabrication of a dental cast [i.e., a positive copy of a part of the oral anatomy made in an impression (mould), such as a dental crown] or dental restorations and appliances (e.g., porcelain-fused-to-metal crowns and bridge restorations). It is typically available in the form of small ingots or bars that are melted and poured into an impression. After application, this device cannot be reused.
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