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Dental caries (tooth decay) is one of the most common of all disorders, second only to the common cold. It usually occurs in children and young adults but can affect any person. It is the most important cause of tooth loss in younger people.
Bacteria (such as peptostreptococci ) are normally present in the mouth. The bacteria convert foods—especially sugar and starch—into acids. Bacteria, acid, food debris, and saliva combine in the mouth to form a sticky substance called plaque that adheres to the teeth. It is most prominent on the grooved chewing surfaces of back molars, just above the gum line on all teeth, and at the edges of fillings . Plaque that is not removed from the teeth mineralizes into calculus ( tartar). Plaque and calculus irritate the gums, resulting in gingivitis and ultimately periodontitis .The acids in plaque dissolve the enamel surface of the tooth and create holes in the tooth (cavities). Cavities are usually painless until they grow very large inside the internal structures of the tooth (the dentin and the pulp at the core) and can cause death of the nerve and blood vessels in the tooth. If left untreated a tooth abscess can develop.
Plaque and bacteria begin to accumulate within 20 minutes after eating, the time when most bacterial activity occurs. If plaque and bacteria are left on the teeth, cavities can develop, and untreated tooth decay can result in death of the internal structures of the tooth and ultimately the loss of the tooth.
Dietary sugars and starches ( carbohydrates) increase the risk of tooth decay. The type of carbohydrate and the timing and frequency of ingestion are more important than the amount. Sticky foods are more harmful than nonsticky foods because they remain on the surface of the teeth. Frequent snacking increases the time that acids are in contact with the surface of the tooth.
An examination of the teeth reveals dental caries (cavities). Most dental caries are discovered in the early stages during routine checkups. The surface of the tooth may be soft when probed with a sharp instrument. Pain may not be present until the advanced stages of tooth decay. Dental X-rays may show some cavities before they are visible to the eye.
Destroyed tooth structure does not regenerate. However, the progression of dental caries can be stopped by treatment. The goal of treatment is to preserve the tooth and prevent complications.
In filling teeth, the decayed material is removed (by drilling) and replaced with a restorative material such as silver alloyAn alloy is a combination, either in solution or compound, of two or more elements, at least one of which is a metal. An alloy with two components is called a binary alloy; one with three is a ternary alloy; one with four is a quaternary alloy. The result, gold, porcelain, or composite resinResin is a hydrocarbon secretion formed in special resin canals of many plants, from many of which (for example, coniferous trees) it is exuded in soft drops from wounds, hardening into solid masses in the air. It may be obtained by making incisions in th. Porcelain and composite resin more closely match the natural tooth appearance, and may be preferred for front teeth. Many dentists consider silver amalgam (alloy) and gold as stronger, and these materials are often used on back teeth, although there is a trend to use high strength composite resin in the back teeth as well.
Crowns are used if decay is extensive and there is limited tooth structure which may cause weakened teeth. Large fillings and weak teeth increase the risk of the tooth breaking. The decayed or weakened area is removed and repaired and a covering jacket or "cap" (crown) is fitted over the remainder of the tooth. Crowns are often made of gold, porcelain or porcelain fused to metal.
A root canalRoot canal refers to the hollow area at the center of a tooth. It can also be used informally to refer to a treatment (also known as endodontic treatment in dentistry used to cure an infection of the root canal. At the center of a tooth is a hollow area t is recommended if the nerve (pulp) in a tooth dies from decay or from a traumatic blow. The center of the tooth, including the nerve and vascular (blood vessel) tissue (pulp), is removed along with decayed portions of the tooth. The roots are filled with a sealing material. The tooth is filled and a crown may be placed over the tooth if needed.