A dental extraction is the removal of a tooth from the mouth

Mouth

The mouth is the first portion of the alimentary canal that receives food andsaliva. The oral mucosa is the mucous membrane epithelium lining the inside of the mouth....

. Extractions are performed for a wide variety of reasons, including tooth decay

Dental caries

Dental caries, also known as tooth decay or a cavity, is an irreversible infection usually bacterial in origin that causes demineralization of the hard tissues and destruction of the organic matter of the tooth, usually by production of acid by hydrolysis of the food debris accumulated on the...

 that has destroyed enough tooth structure to render the tooth non-restorable. Extractions of impacted or problematic wisdom teeth are routinely performed, as are extractions of some permanent teeth to make space for orthodontic treatment

Orthodontics

Orthodontics, orthodontia, or orthodonture is the first specialty of dentistry that is concerned with the study and treatment of malocclusions , which may be a result of tooth irregularity, disproportionate jaw relationships, or both...

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Historically, dental extractions have been used to treat a variety of illnesses, as well as a method of torture to obtain forced confessions.