A dental extraction or removal of a tooth from the mouth is done for a variety of reasons.  Tooth decay can destroy the structure of the tooth hindering the dentist from restoring the tooth with a filling or crown.  Gum disease or periodontitis can destroy the bone and supporting structures around the tooth causing the tooth to become loose and unable to maintain normal function in the mouth.  A tooth can also fracture from clenching or grinding teeth together.  If this happens, then it is non-restorable and must be removed before infection occurs causing pain and swelling for the patient.  Usually dental extractions are completed under local anesthesia, but sedation is used in many cases like the removal of wisdom teeth.