An impacted tooth is a dental disorder in which a tooth fails to fully emerge through the gums.
Teeth emerge through the gums during infancy and also when primary (baby) teeth are replaced by the permanent teeth. If a tooth fails to emerge or emerges only partially, it is considered impacted. The teeth most commonly impacted are the wisdom teeth (or third molars). These teeth are the last to develop, but don't begin breaking through the bone and gum tissue until the later teen years. By this time, the upper and lower jaws have stopped growing and may be too small to accommodate these four additional teeth. As the wisdom teeth continue to grow, one or more may become impacted. If there is not enough room in the mouth to accommodate these teeth, they will remain trapped in the jawbone.
Impacted teeth can take many positions in the bone as they attempt to find a pathway that will allow them to erupt. According to the American Board of Oral and Maxillary Surgeons nine out of every ten people have an impacted tooth. Impacted tooth surgery is the leading surgical problem faced by general dentists and oral surgeons.
Causes and symptoms
An impacted tooth may be caused by overcrowding of the teeth often because the jaw is too small. Teeth may also become twisted, tilted, or displaced as they try to emerge. Less common symptoms of an impacted tooth may be:
- pain and tenderness of the gums
- visible gap where a tooth has not emerged
- redness and swelling of the gums around the impacted tooth area
- swollen lymph nodes of the neck
- difficulty opening the mouth
- prolonged headaches or jaw ache
- unpleasant taste when biting down on or near the impacted area
- raised gum tissue where impacted tooth lies under the gum tissue
Upon visual examination, the dentist may find signs of infection or swelling in the area where the tooth is absent or only partially erupted. Dental x rays are essential in diagnosing an impacted tooth. The dentist may also see signs of enlargement of the tissue over the area where a tooth has not emerged, or has emerged only partially. The impacted tooth may also be pressing on an adjacent tooth causing pain.
The goal of treatment is to relieve irritation of the mouth and remove pain caused by the impacted tooth. If the impacted tooth is not causing infection or inflammation, or is not affecting the alignment of the other teeth, no treatment may be necessary. Warm, salt-water rinses may be advised to aid in soothing the swollen gums.
A dentist may perform an extraction with forceps and local anesthetic agent if the tooth is exposed and appears to be easily removable. Extracting an impacted tooth typically requires making an incision through gum tissue to expose the tooth and may require removing portions of bone to free the tooth. The tooth may have to be removed in pieces to minimize destruction to the surrounding bone and tissue. The extraction site may require one or more stitches to aid healing.
Another type of treatment called ligation is performed on impacted teeth in conjunction with orthodontics. A small portion of the crown of an impacted tooth is exposed through the gum tissue and a small orthodontic bracket is attached to the exposed area so that the tooth can be brought into alignment with the rest of the teeth while the patient is being orthodontically treated. An oral and maxillofacial surgeon commonly performs this type of treatment.
Antibiotics may be required after the extraction or ligation if the area is infected or there is a risk of infection. Over the counter pain medications, such as Tylenol, Advil, or Motrin may be taken to lessen the pain of the treated area. This pain will gradually decrease over two to three days.
The prognosis is very good for the removal or ligation of an impacted tooth. Potential complications include postoperative infection, temporary numbness from nerve irritation, jaw fracture, and jaw joint pain. A painful condition, which may develop after an extraction, is known as a dry socket, when a blood clot does not completely fill the empty tooth socket, or is disturbed by an oral vacuum, by drinking through a straw, or by smoking. The bone beneath the socket is painfully exposed to air. The general dentist will pack the socket with medication to allow healing to take place. One complication of the ligation process is that the bracket and chain may come off and will need to be replaced by the oral and maxillofacial surgeon.
Health care team roles
Extraction of a symptomatic impacted tooth is often treated in a general dental office. If the tooth is deeply impacted or more difficult to remove than expected the general dentist may refer the patient to an oral and maxillofacial surgeon.
There is no way to prevent an impacted tooth. Heredity plays a role in the growth and development of the jaw, making it hard to prevent an impacted tooth from happening. Complications with an impacted tooth can be prevented by patient education, good oral hygiene, and proper care of the extraction area.
Dry socket— A painful condition following tooth extraction in which a blood clot does not properly fill the empty socket, leaving the bone underneath exposed to air and food.
Eruption— The process of a tooth breaking through the hard and soft oral tissue to grow into place in the mouth.
Extraction— The surgical removal of a tooth from its socket in the bone.
Ligated— Where a small chain and wire are glued to the impacted tooth by an oral and maxillofacial surgeon. The wire is tightened during monthly visits with an orthodontist. This brings the tooth out of the bone and gum tissue and into alignment with the other teeth.
Oral and maxillofacial surgeon— A dentist specializing in oral and maxillofacial surgical procedures of the mouth.
Wisdom teeth— Also called third molars, the last teeth to erupt in the upper and lower jawbone.
Frank, Charles A. "Treatment Options for Impacted Teeth." Journal of The American Dental Association (May 2000): 623.
American Association of Oral and Maxillofacial Surgeons, 9700 West Bryn Mawr Avenue, Rosemont, IL 60018-5701. (847) 678-6200. 〈http://www.aaoms.org〉.
American Board of Oral and Maxillofacial Surgeons, 625 North Michigan Avenue, Suite 1820, Chicago, Illinois 60611. (312) 642-0070. 〈http://www.aaoms.org〉.
American Dental Association, 211 East Chicago Avenue, Chicago, IL 60611. (312) 440-2500. 〈http://www.ada.org〉.
Ashman, Steven G. "Impacted Tooth," July 1999. 〈http://dr.ashman.com/sg00059.htm〉.
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