Biomaterial Database

Dentinal and pulpal uptake of mercury from lined and unlined amalgam restorations in minipigs. 1997

P Hörsted-Bindslev, and G Danscher, and J C Hansen

Department of Dental Pathology, Operative Dentistry and Endodontics, Royal Dental College, Aarhus C, Denmark.

The aim of the present investigation was to examine dentin and pulp in amalgam-restored teeth in minipigs with respect to presence of mercury, and to evaluate whether lining of restored cavities with a resin-modified glass ionomer cement had any effect on the penetration of mercury. Class I and V cavities were cut in 49 posterior and canine teeth of 4 minipigs. 35 cavities were restored with amalgam and 14 with composite material. 26 of the amalgam cavities were lined with a resin-modified glass ionomer cement. Following observation periods of 17-28 months, the pigs were killed and the jaws sectioned. After decalcification, the teeth were processed for light or electron microscopy examinations. Mercury was visualized by autometallography. Silver-enhanced mercury was found in all teeth with amalgam, whereas teeth with composites were devoid of mercury. Mercury could be traced in the odontoblast processes, in the body of odontoblasts, and on rare occasions in the nerve tissue of the pulp from lined and from unlined amalgam restorations. The present study thus demonstrates transport of mercury through dentinal tubules to the pulp, and that lining of cavities with a resin-modified glass ionomer cement does not prevent penetration of mercury.

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.
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D008963	Molar	The most posterior teeth on either side of the jaw, totaling eight in the deciduous dentition (2 on each side, upper and lower), and usually 12 in the permanent dentition (three on each side, upper and lower). They are grinding teeth, having large crowns and broad chewing surfaces. (Jablonski, Dictionary of Dentistry, 1992, p821)	Molars
D009417	Nerve Tissue	Differentiated tissue of the central nervous system composed of NERVE CELLS, fibers, DENDRITES, and specialized supporting cells.	Nervous Tissue,Nerve Tissues,Nervous Tissues,Tissue, Nerve,Tissue, Nervous,Tissues, Nerve,Tissues, Nervous
D009804	Odontoblasts	The mesenchymal cells which line the DENTAL PULP CAVITY and produce DENTIN. They have a columnar morphology in the coronal pulp but are cuboidal in the root pulp, or when adjacent to tertiary dentin.	Odontoblast
D003188	Composite Resins	Synthetic resins, containing an inert filler, that are widely used in dentistry.	Composite Resin,Resin, Composite,Resins, Composite
D003481	Cuspid	The third tooth to the left and to the right of the midline of either jaw, situated between the second INCISOR and the premolar teeth (BICUSPID). (Jablonski, Dictionary of Dentistry, 1992, p817)	Canine Tooth,Canine Teeth,Cuspids,Teeth, Canine,Tooth, Canine
D003723	Dental Amalgam	An alloy used in restorative dentistry that contains mercury, silver, tin, copper, and possibly zinc.	Amalgam, Dental,Amalgams, Dental,Dental Amalgams
D003736	Dental Cavity Lining	An inner coating, as of varnish or other protective substance, to cover the dental cavity wall. It is usually a resinous film-forming agent dissolved in a volatile solvent, or a suspension of calcium hydroxide in a solution of a synthetic resin. The lining seals the dentinal tubules and protects the pulp before a restoration is inserted. (Jablonski, Illustrated Dictionary of Dentistry, 1982)	Varnish, Cavity,Cavity Liner, Dental,Cavity Lining Varnish,Cavity Lining Varnishes,Cavity Lining, Dental,Cavity Linings, Dental,Cavity Varnishes,Dental Cavity Liner,Dental Cavity Liners,Dental Cavity Linings,Liners, Dental Cavity,Lining, Dental Cavity,Linings, Dental Cavity,Cavity Liners, Dental,Cavity Varnish,Liner, Dental Cavity,Varnish, Cavity Lining,Varnishes, Cavity,Varnishes, Cavity Lining
D003737	Dental Cavity Preparation	An operation in which carious material is removed from teeth and biomechanically correct forms are established in the teeth to receive and retain restorations. A constant requirement is provision for prevention of failure of the restoration through recurrence of decay or inadequate resistance to applied stresses. (Boucher's Clinical Dental Terminology, 4th ed, p239-40)	Cavity Preparation, Dental,Cavity Preparations, Dental,Dental Cavity Preparations,Preparation, Dental Cavity,Preparations, Dental Cavity