Biomaterial Database

Equilibrium vapor pressure of mercury from dental amalgam in vitro. 1996

D M Wieliczka, and P Spencer, and C E Moffitt, and E J Wagner, and A Wandera

Department of Physics, University of Missouri-Kansas City, USA.

OBJECTIVE The purpose of this study was to acquire reliable quantitative data on mercury vapor pressure above the surface of dental amalgam samples in both the as-formed and the abraded state. METHODS The equilibrium vapor pressure of mercury from dental amalgam was obtained using residual gas analysis in conjunction with a quartz crystal microbalance. The measurements were performed under ultrahigh-vacuum conditions. RESULTS Using the residual gas analyzer, the average mercury vapor pressures measured from the as-formed and abraded dental amalgam surfaces were 8 x 10(-7) and 1.7 x 10(-4) Pa, respectively. The corresponding vapor densities are: 6 x 10(-2) micrograms/m3 and 14 micrograms/m3. The average mercury vapor pressures measured from the as-formed and abraded dental amalgam surfaces using the quartz crystal microbalance were: 2.4 x 10(-6) and 1.0 x 10(-4) Pa, respectively. The corresponding vapor densities are: 0.2 microgram/m3 and 8 micrograms/m3. CONCLUSIONS This project provides a measurement of the equilibrium vapor pressure of mercury from as-formed and abraded amalgam surfaces. By definition, the equilibrium vapor pressure provides the maximum density of mercury which can be present in the environment above the amalgam. The vapor density of mercury within the oral cavity must be less than this value due to the dynamic nature of the system.

UI	MeSH Term	Description	Entries
D008628	Mercury	A silver metallic element that exists as a liquid at room temperature. It has the atomic symbol Hg (from hydrargyrum, liquid silver), atomic number 80, and atomic weight 200.59. Mercury is used in many industrial applications and its salts have been employed therapeutically as purgatives, antisyphilitics, disinfectants, and astringents. It can be absorbed through the skin and mucous membranes which leads to MERCURY POISONING. Because of its toxicity, the clinical use of mercury and mercurials is diminishing.
D011312	Pressure	A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Pressures
D002627	Chemistry, Physical	The study of CHEMICAL PHENOMENA and processes in terms of the underlying PHYSICAL PHENOMENA and processes.	Physical Chemistry,Chemistries, Physical,Physical Chemistries
D003300	Copper	A heavy metal trace element with the atomic symbol Cu, atomic number 29, and atomic weight 63.55.	Copper-63,Copper 63
D003722	Dental Alloys	A mixture of metallic elements or compounds with other metallic or metalloid elements in varying proportions for use in restorative or prosthetic dentistry.	Alloy, Dental,Alloys, Dental,Dental Alloy
D003723	Dental Amalgam	An alloy used in restorative dentistry that contains mercury, silver, tin, copper, and possibly zinc.	Amalgam, Dental,Amalgams, Dental,Dental Amalgams
D005740	Gases	The vapor state of matter; nonelastic fluids in which the molecules are in free movement and their mean positions far apart. Gases tend to expand indefinitely, to diffuse and mix readily with other gases, to have definite relations of volume, temperature, and pressure, and to condense or liquefy at low temperatures or under sufficient pressure. (Grant & Hackh's Chemical Dictionary, 5th ed)
D013499	Surface Properties	Characteristics or attributes of the outer boundaries of objects, including molecules.	Properties, Surface,Property, Surface,Surface Property
D014835	Volatilization	A phase transition from liquid state to gas state, which is affected by Raoult's law. It can be accomplished by fractional distillation.	Vaporization,Volatility
D055598	Chemical Phenomena	The composition, structure, conformation, and properties of atoms and molecules, and their reaction and interaction processes.	Chemical Concepts,Chemical Processes,Physical Chemistry Concepts,Physical Chemistry Processes,Physicochemical Concepts,Physicochemical Phenomena,Physicochemical Processes,Chemical Phenomenon,Chemical Process,Physical Chemistry Phenomena,Physical Chemistry Process,Physicochemical Phenomenon,Physicochemical Process,Chemical Concept,Chemistry Process, Physical,Chemistry Processes, Physical,Concept, Chemical,Concept, Physical Chemistry,Concept, Physicochemical,Concepts, Chemical,Concepts, Physical Chemistry,Concepts, Physicochemical,Phenomena, Chemical,Phenomena, Physical Chemistry,Phenomena, Physicochemical,Phenomenon, Chemical,Phenomenon, Physicochemical,Physical Chemistry Concept,Physicochemical Concept,Process, Chemical,Process, Physical Chemistry,Process, Physicochemical,Processes, Chemical,Processes, Physical Chemistry,Processes, Physicochemical