NBDE Examination Practice Question # 107
NBDE Examination.
Practice Question # 107.
nbde examination
Dental amalgam is the most widely used restorative material. It has been in use for over 150 years. Dental amalgam is a mixture of a silver alloy with mercury. The silver alloy is a fine powder that is composed mostly of silver, tin and copper, and sometimes zinc, palladium or indium. When the silver alloy and mercury are mixed, a chemical reaction occurs that forms dental amalgam. This reaction between alloy and mercury is termed as amalgamation reaction. Although some forms of mercury are hazardous, the mercury in amalgam is chemically bound to the other metals to make it stable and therefore safe for use in dental applications.
Dental amalgam is used in all surfaces of posterior teeth and occasionally in the lingual pits of anterior teeth. Amalgam restorations account for a significant portion of all dental restorations. However, because of its silvery-gray appearance, restorations are limited to posterior teeth. The popularity of dental amalgam results from its cost-effectiveness, durability and the ease of use.