The history of dental amalgam
Created by mercuryexposure on Nov 18, 2010
Last updated: 04/18/13 at 11:51 AM
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the Domestic Policy Subcommittee held a hearing entitled, "Assessing EPA's Efforts to Measure and Reduce Mercury Pollution from Dentist Offices." This is the Subcommittee's third hearing on this topic. The purpose of this hearing is to examine a number of developments at EPA that merit continued oversight by the Subcommittee.
This hearing examined the environmental risks of mercury in dental fillings (known as dental mercury amalgam) and the government’s regulatory response to it.
Dental offices are the third-largest user of mercury in the United States. Mercury contained in the existing dental fillings of Americans comprises over half of all mercury in use today, amounting to more than 1,000 tons. According to the U.S. Environmental Protection Agency (EPA), “Mercury discharges (in wastewater) from dental offices far exceeded all other commercial and residential sources.” These discharges may have a significant negative effect on the environment. Sludge, the mercury-contaminated byproduct of municipal sewage treatment plants, is often incinerated, causing the formation of “methylmercury,” the most toxic and dangerous form of mercury.
EPA’s only dental mercury-specific program is an educational program to encourage new dentists to use equipment to prevent mercury from entering the wastewater.
Mercury dental devices are regulated by the Food and Drug Administration (FDA), but FDA has never conducted an environmental assessment of the use of dental mercury amalgam as prescribed by law.
Witnesses for the November 14 hearing include:
Mr. Ephraim King, Director, Office of Science and Technology, Office of Water, Environmental Protection Agency
Dr. Norris Alderson, Director, Office of Science and Health Coordination, Food and Drug Administration
Mr. Ray Clark, Senior Partner, The Clark Group, LLC
Mr. Bruce Terris, Partner, Terris, Pravlik & Millian, LLP
Mr. C. Mark Smith, Co-Chair, Mercury Task Force, New England Governor’s Conference
Mr. Michael Bender, Executive Director, Mercury Policy Project
Mr. Rod Mackert, Dentist and Faculty Member, Medical College of Georgia
A dentist named G.V. Black (1836-1915) finally laid the foundation for the correct formulation and use of the new material and essentially revolutionized the profession of dentistry by standardizing the repair of teeth and making dentistry affordable to the average citizen. He standardized the formula for Amalgam in 1896, mixing components to create suitable expansion properties and setting exact limits on the amount of mercury necessary for its formulation. Prior to Black, dental amalgam had been formulated by hand out of shaved coin silver mixed with however much mercury the dentist felt like using. This mixture often underwent expansion on setting and would crack the teeth. Black had a knowledge of materials science and got the formula right.
Amalgam was re-invented in the west in France in 1816 by Auguste Taveau of Paris and consisted of shavings from silver coins mixed with mercury. Prior to that time, attempts to fill teeth had been made using numerous materials, but the most reliable was found to be lead foil compressed into a cavity preparation. Amalgam in those early days had serious drawbacks since its physical characteristics depended on the exact proportions of silver and mercury, and the mixture often expanded on setting causing the tooth to crack. Anderson MH, McCoy RB. Dental amalgam: The state of the art and science. 3rd Ed. (Philadelphia: Saunders, 1993)
British Chemist Joseph Bell is credited with inventing mercury amalgam.