Amalgam (dentistry) Amalgam (dentistry) Dental amalgam is a liquid mercury and metal alloy mixture used in dentistry to fill cavities caused by tooth decay. Low-copper amalgam commonly consists of mercury (50%), silver (~22–32%), tin (~14%), copper (~8%) and other trace metals. Dental amalgams were first documented in a Tang Dynasty medical text written by Su Gong 苏恭 in 659, and appeared in Germany in 1528. In the 1800s, amalgam became the dental restorative material of choice due to its low cost, ease of application, strength, and durability. There are, according to Geir Bjørklund, indications that dental amalgam was used in the first
What Is History? to suit their facts, and takes part in a dialogue between past and present. Summing up his argument, Carr puts forward his own answer to the question of "what is history?", remarking that "it is a continuous process of interaction between the historian and his facts, an unending dialogue between the past and the present." it is precisely for matters of this kind that the historian is entitled to rely on what have been called the auxiliary sciences of history In his second chapter, Carr focuses on the influence that society plays on forming the approach of the historian and