Dental fillings, amalgam

In a UK study, single oral doses of dimercaptopropane sulfonic acid or succimer in different combinations with or without acetylcysteine and potassium citrate were given to 191 patients considered to have mercury toxicity from amalgam dental fillings (2). After a single dose, about 5% of patients complained of mild gastrointestinal discomfort, fatigue, mental fuzziness, headache, and diuresis. These usually cleared within 6 hours of the dose and were considered to be due to heavy metal mobilization. There were no cases of hypersensitivity. 

BatesMN. "Mercury amalgam dental fillings an epidemiologic assessment."IntJ Hyg Environ Health 2006 209 309-16 Riddle M, Gardner E, Beswick I, Filshie I. The nephrotic syndrome complicating mercurial diuretic therapy. Brit Med J 1958 1 1274-7. 

A source of mercury other than the workplace has now assumed ascendancy in driving public unease. Recent publicity has indicted mercury amalgam dental fillings as a source of adverse health effects. Although it is true that chewing can release mercury... 

Hazardous Decomp. Prods. Heated to decomp., emits toxic fumes of Hg HMIS Health 3, Flammability 0, Reactivity 1 Uses Amalgam dental fillings catalyst electrical apparatus cathodes for prod, of chlorine and caustic soda instrument indicator fluid thermometers barometers mercury vapor arc lamps extraction metallurgy mirror coating boilers coolant and neutron absorber in nuclear power plants vacuum pumps... 

The Department of Health Washington State, Amalgam Dental Fillings http //www.doh.wa.gov/ehp/oehas/ amalgam dentaLfillings 12-2003.htm, 2003... 

Gold inlay touching amalgam dental filling... 

Mechanical interlocking probably plays a part in the adhesion of ice to glass. Silver amalgam dental fillings are held in place largely by mechanical interlocking. Although there probably are some exceptions, mechanical... 

Feuerman, E. J. (1975) Recurrent contact dermatitis caused by mercury in amalgam dental fillings. Int. / Dermatol., 14,657. 

The metal is slowly oxidised by air at its boiling point, to give red mercury(II) oxide it is attacked by the halogens (which cannoi therefore be collected over mercury) and by nitric acid. (The reactivity of mercury towards acids is further considered on pp. 436, 438.) It forms amalgams—liquid or solid—with many other metals these find uses as reducing agents (for example with sodium, zinc) and as dental fillings (for example with silver, tin or copper). 

Dentistry. Mercury is used in dental amalgams for fillings in teeth (see Dental materials). Dental uses have accounted for 2—4% of total U.S. mercury consumption since 1980 and generally 3—6% before that time (3). Dental amalgams used to fill cavities in teeth are approximately 50% mercury by weight. Dental use of mercury can be expected to continue to decrease, in part because of more effective cavity prevention as well as development and increasing use of alternative dental materials such as plastics and ceramics, and increasing awareness of the environmental and health effects of mercury. 

Martin, D. M., DeRouen, T. A. and Leroux, B. G. (1997). Is mercury amalgam safe for dental fillings Washington Public Health, 15(Fall), 30-32. MMWR. (1996a). Mercury exposure among residents of a building formerly used for industrial purposes - New Jersey, 1995. Morbidity Mortality Weekly Report, 45(20), 422-424- Online. Available HTTP (accessed 5 July 2003). 

Daniel Gray perfected a stable bath from which indium can be plated simultaneously with other elements (90). Alloyed with precious metals, indium has been made into jewelry, alloyed with silver, it is sometimes used to plate silverware with a suiface resistant to tarnish in the form of an amalgam, it can be used for dental fillings (88, 89, 93) The portraits of Reich and Richter and much of the information about indium have been obtained through the kind assistance of Professor L. W. McCay of Princeton University and Professor O. Brunck, Rectoi of the Freiberg Academy. 

Solutions aren t necessarily liquids. Air is a solution of nitrogen, oxygen, and a few other minor gases. Mixtures of oxygen and nitrous oxide are also solutions. Dental fillings used to be made of silver amalgams, which are solid solutions of silver and mercury. 

Mercury has been used for more fhan 150 years in dental silver amalgams. Dental silver amalgams in tooth fillings are composed of a mixture of 50% metalhc mercury and metal powder, usuaUy silver, tin, copper and zinc. 

But even as recendy as the mid-20th cenmry, there was relatively litde concern about mercury metal and many mercury compounds. High school chemistry students often played with tiny droplets of mercury in the laboratory. They used mercury to coat pennies and other pieces of metal. Mercury was also widely used in dentistry. It was used to make amalgams, alloys of mercury with other metals, used to fill teeth. Most people even today are likely to have dental fillings that contain a small amount of mercury metal. The question of whether mercury is still safe to use in... 

After 12-14 hours of exposure of rats to a relatively small amount of metallic mercury vapor (0.55 mg/m3), accumulation of mercury was observed within all cell types examined (ganglion cells, satellite cells, fibroblasts, and macrophages). Mercury has also been detected in dorsal root neurons and satellite cells of primates exposed for one year to mercury through amalgams in dental fillings or the maxillary bone (Danscher et al. 1990). 

Heterogeneous alloys include tin-lead solder and mercury amalgams for dental fillings. 

In another type of mixture, the boundaries between the substances cannot be seen. This is called a homogeneous mixture. Its composition is uniform throughout. Homogeneous mixtures are also called solutions. Solutions are crucial to life and to many processes. We often encounter them in daily life. The air we breathe, our soft drinks, the amalgam used in dental fillings, the alloys used in the production of cars, the fog that causes traffic jams, coins, seas, lakes, and even our own body fluids are solutions. 

Dental amalgam Mercury, silver, tin, copper, zinc Dental fillings... 

Solutions include different combinations in which a solid, liquid, or gas acts as either solvent or solute. Usually the solvent is a liquid. For instance, sea water is an aqueous solution of many salts and some gases such as carbon dioxide and oxygen. Carbonated water is a saturated solution of carbon dioxide in water. Solutions are common in nature and are extremely important in all life processes, in all scientific areas, and in many industrial processes. The body fluids of all forms of life are solutions. Variations in concentrations of our bodily fluids, especially those of blood and urine, give physicians valuable clues about a person s health. Solutions in which the solvent is not a liquid are also common. Air is a solution of gases with variable composition. Dental fillings are solid amalgams, or solutions of liquid mercury dissolved in solid metals. Alloys are solid solutions of solids dissolved in a metal. 

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