Dental fillings are inserted as restorations in the treatment of dental cavities, after drilling out the cavities. The purpose of drilling is to remove the enamel and dentin that has had its structural integrity compromised by the invasion of acid-producing bacteria. However, once the infected hard tissues have been removed, the resulting cavity preparation must be filled in order to restore structural integrity to the tooth. This will prevent further damage to the tooth and hopefully avoid the eventual need for the tooth to be extracted. Tooth decay, or dental caries, is a disease of the teeth resulting in damage to tooth structure. ...

Amalgam

Amalgam fillings are an alloy of mercury (from 43% to 54%) along with silver, tin, and copper. Mercury-based fillings were apparently first used by French dentists in the 1810s. They continue to be used in some countries because of their hardness and durability and because they are inexpensive. An amalgam is any alloy of mercury. ... An alloy is a combination, either in solution or compound, of two or more elements, which has a combination of at least one metal, and where the resultant material has metallic properties. ... General Name, Symbol, Number mercury, Hg, 80 Chemical series transition metals Group, Period, Block 12, 6, d Appearance silvery white Atomic mass 200. ... General Name, Symbol, Number silver, Ag, 47 Chemical series transition metals Group, Period, Block 11, 5, d Appearance lustrous white metal Atomic mass 107. ... General Name, Symbol, Number tin, Sn, 50 Chemical series poor metals Group, Period, Block 14, 5, p Appearance silvery lustrous gray Atomic mass 118. ... General Name, Symbol, Number copper, Cu, 29 Chemical series transition metals Group, Period, Block 11, 4, d Appearance metallic brown Atomic mass 63. ... Events and Trends End of the Napoleonic Wars in Europe (1803 - 1815). ...

Mercury vapor is toxic, and the use of amalgam fillings is therefore controversial, as the fillings do emit mercury as a minute amount of vapor. Some government agencies, including the UN's World Health Organization and Centers for Disease Control and Prevention, claim that amalgam fillings are safe, even for pregnant women, children, and diabetics, except in rare cases of allergy. The Food and Drug Administration has never approved amalgam for use in dental fillings and is meanwhile opposing its use but amalgam fillings are legally considered "devices" and therefore outside the regulatory control of the FDA. For a list of biologically injurious substances, including toxins and other materials, as well as their effects, see poison. ... Look up Controversy on Wiktionary, the free dictionary A controversy is a contentious dispute, a disagreement in opinions over which parties are actively arguing. ... The WHO flag: similar to the flag of the United Nations, augmented with the symbolic staff and serpent of Asklepios, Greek god of medicine and healing. ... WHY IS THE CDC headquartered in Atlanta? Who made this decision? Was it political? Was there a powerful senator/politician? PLease answer!! The Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia, is recognized as the lead United States agency for protecting the public health and safety of people... This article is about the disease that features high blood sugar. ... An allergy or Type I hypersensitivity is an immune malfunction whereby a persons body is hypersensitised to react immunologically to typically nonimmunogenic substances. ... The United States Food and Drug Administration (FDA) is the government agency responsible for regulating food (human and animal), dietary supplements, drugs (human and animal), cosmetics, medical devices (human and animal), biologics and blood products in the United States. ...

See also: Dental amalgam controversy This article is in need of attention from an expert on the subject. ...

Composite resin

Composite resin fillings are a mixture of powdered glass and plastic resin, and can be made to resemble the appearance of the natural tooth. They are strong and durable and cosmetically superior to silver or dark grey colored amalgam fillings. Composite resin fillings are usually more expensive than silver amalgam fillings. They contain Bisphenol A a known endocrine disrupter chemical. The term composite can refer to several different things: A composite number is an integer greater than one that is not a prime number. ... Insect trapped in resin. ... For eyeglasses, see glasses. ... Plastic bottles for recycling Plastic is a term that covers a range of synthetic or semisynthetic polymerization products. ...

Most modern composite resins are light-cured, causing a polymerization reaction to occur within the material. Once the composite hardens completely, the filling can then be polished to achieve maximum aesthetic results. Composite resins experience a very small amount of shrinkage upon curing, causing the material to pull away from the walls of the cavity preparation. This makes the tooth slightly more vulnerable to microleakage and recurrent decay. With proper technique and material selection, microleakage can be minimized or eliminated altogether.

Besides the aesthetic advantage of composite fillings over amalgam fillings, the preparation of composite fillings requires less removal of tooth structure to achieve adequate bond strength. This is because composite resins bind to enamel (and dentin too, although not as well) via a micromechanical bond. As conservation of tooth structure is a key ingredient in tooth preservation, many dentists prefer placing composite over amalgam fillings when possible. The word enamel can mean more than one thing: Tooth enamel Vitreous enamel Enamel (markup language) Enameled wire This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... Parts of a tooth, including dentin Dentin (BE: dentine) is the substance between the enamel (substance in the crown) or cementum (substance in the root) of a tooth and the pulp chamber. ...

Generally, composite fillings are used to fill a carious lesion involving highly visible areas (such as the central incisors or any other teeth that can be seen when smiling) or when conservation of tooth structure is a top priority.

Glass Ionomer Cement

These fillings are a mixture of glass and an organic acid. Although they are tooth-colored, glass ionomers vary in translucency. Although glass ionomers can be used to achieve an aesthetic result, their aesthetic potential does not measure up to that provided by composite resins. For eyeglasses, see glasses. ...

The cavity preparation of a glass ionomer filling is the same as a composite resin; it is considered a fairly conservative procedure as the bare minimum of tooth structure should be removed.

Conventional glass ionomers are chemically set via an acid-base reaction. Upon mixing of the material components, there is no light cure needed to harden the material once placed in the cavity preparation. After the initial set, glass ionomers still need time to fully set and harden.

Glass ionomers do have their advantages over composite resins:

1. They are not subject to shrinkage and microleakage, as the bonding mechanism is an acid-base reaction and not a polymerization reaction.

2. Glass ionomers contain and release fluoride, which is important to preventing carious lesions. Furthermore, as glass ionomers release their fluoride, they can be "recharged" by the use of fluoride-containing toothpaste. Hence, they can be used as a treatment modality for patients who are at high risk for caries. Newer formulations of glass ionomers that contain light-cured resins can achieve a greater aesthetic result, but do not release fluoride as well as conventional glass ionomers.

Glass ionomers are about as expensive as composite resin. The fillings do not wear as well as composite resin fillings. Still, they are generally considered good materials to use for root caries and for sealants.

Resin-Ionomer Cement

A combination of glass-ionomer and composite resin, these fillings are a mixture of glass, an organic acid, and resin polymer that harden when light cured. (The light activates a catalyst in the cement that causes it to cure in seconds.) The cost is similar to composite resin. It holds up better than glass ionomer, but not as well as composite resin, and is not recommended for biting surfaces of adult teeth. For eyeglasses, see glasses. ... Polymer is a generic term used to describe a very long molecule consisting of structural units and repeating units connected by covalent chemical bonds. ... A catalyst (Greek: καταλύτης, catalytēs) is a substance that accelerates the rate (speed) of a chemical reaction without itself being transformed or consumed by the reaction (see also catalysis). ...

In general, resin-ionomer cements can achieve a better aesthetic result than conventional glass ionomers, but not as good as pure composites.

Porcelain (ceramic)

Porcelain fillings are hard, but can cause wear on opposing teeth. They are brittle and are not always recommended for molar fillings. A rare Dresden porcelain figurine Porcelain is a hard ceramic material first developed in China (hence the often-used term china instead of porcelain). It is fired at a higher temperature than that used to fire glazed earthenware and stoneware pottery. ... A molar is the fourth kind of tooth in mammals. ...

Porcelain Fused to Metal

These are metal shells with porcelain "enameled" on top, and is used for crowns. They are very durable. Crown A crown (sometimes incorrectly called a cap) is a tooth form produced by a dental technician in conjunction with a dentist. ...

Nickel or Cobalt-Chrome Alloys

These are mixtures of nickel and chromium and are used for crowns and bridges. They can be abrasive to opposing teeth and do conduct heat and cold, but have excellent durability. General Name, Symbol, Number nickel, Ni, 28 Chemical series transition metals Group, Period, Block 10, 4, d Appearance lustrous, metallic Atomic mass 58. ... General Name, Symbol, Number chromium, Cr, 24 Chemical series transition metals Group, Period, Block 6, 4, d Appearance silvery metallic Atomic mass 51. ...

Gold

Gold fillings have excellent durability, wear well, and do not cause excessive wear to the opposing teeth, but they do conduct heat and cold, which can be irritating. For years, they have been considered the gold standard as a restorative dental material. Recent advances in dental porcelains and consumer focus on aesthetic results have caused demand for gold fillings to drop in favor of advanced composites and porcelain veneers and crowns. Gold fillings are usually quite expensive, although they do last a very long time. It is not uncommon for a gold crown to last 30 years in a patient's mouth.

Other historical fillings

Lead fillings were used in the 1700s, but became unpopular in the 1800s because of their softness and because lead poisoning was understood. Events and trends The Bonneville Slide blocks the Columbia River near the site of present-day Cascade Locks, Oregon with a land bridge 200 feet (60 m) high. ... Events and Trends Beginning of the Napoleonic Wars (1803 - 1815). ... Lead poisoning is a condition, also known as plumbism or painters colic, caused by increased blood serum lead levels. ...

According to U.S. Civil War-era dental handbooks from the mid-1800s, since the early 1800s metallic fillings had been used, made of lead, gold, tin, platinum, silver, aluminum, or amalgam. A pellet was rolled slightly larger than the cavity, condensed into place with instruments, and then shaped and polished in the patient's mouth. The filling was usually left "high", with final condensation — "tamping down" — occurring through the patient's chewing of food. Gold was the preferred filling material during the Civil War, with amalgam being the most common due to cost. Tin was also popular due to cost, but was held in lower regard. The American Civil War was fought in the United States from 1861 until 1865 between the northern states, popularly referred to as the U.S., the Union, the North, or the Yankees; and the seceding southern states, commonly referred to as the Confederate States of America, the CSA, the Confederacy... Events and Trends Beginning of the Napoleonic Wars (1803 - 1815). ... General Name, Symbol, Number lead, Pb, 82 Chemical series poor metals Group, Period, Block 14, 6, p Appearance bluish white Atomic mass 207. ... General Name, Symbol, Number gold, Au, 79 Chemical series transition metals Group, Period, Block 11, 6, d Appearance metallic yellow Atomic mass 196. ... General Name, Symbol, Number tin, Sn, 50 Chemical series poor metals Group, Period, Block 14, 5, p Appearance silvery lustrous gray Atomic mass 118. ... General Name, Symbol, Number platinum, Pt, 78 Chemical series transition metals Group, Period, Block 10, 6, d Appearance grayish white Atomic mass 195. ... General Name, Symbol, Number silver, Ag, 47 Chemical series transition metals Group, Period, Block 11, 5, d Appearance lustrous white metal Atomic mass 107. ... Aluminum is a soft and lightweight metal with a dull silvery appearance, due to a thin layer of oxidation that forms quickly when it is exposed to air. ... An amalgam is any alloy of mercury. ...

One survey [1] of dental practices in the mid-1800s catalogued dental fillings found in the remains of seven Confederate soldiers from the U.S. Civil War; they were made of:

• Thorium — radioactivity was unknown at that time, and the dentist probably thought he was working with tin
• Lead and tungsten mixture, probably coming from shotgun pellets
• Tin and iron
• Mercury amalgam
• Three soldiers had gold fillings

General Name, Symbol, Number thorium, Th, 90 Chemical series transition metals Group, Period, Block ?, 7, f Appearance silvery white Atomic mass 232. ... General Name, Symbol, Number tungsten, W, 74 Chemical series transition metals Group, Period, Block 6, 6, d Appearance grayish white, lustrous Atomic mass 183. ... General Name, Symbol, Number iron, Fe, 26 Chemical series transition metals Group, Period, Block 8, 4, d Appearance lustrous metallic with a grayish tinge Atomic mass 55. ...

See also

• Anesthesia
• Dental caries
• Dentistry
• Oral hygiene

For the song (Anesthesia) Pulling Teeth by Metallica, go here. ... X-rays can reveal if a person has cavities Dentistry is the practical application of knowledge of dental science (the science of placement, arrangement, function of teeth and their supporting bones and soft tissues) to human beings. ... It has been suggested that tooth be merged into this article or section. ...

References

• Dental Materials Fact Sheet, Dental Board of California, May 2004