Tooth Extraction | Dental Surgery
A dental extraction (also referred to as tooth extraction, exodontia, exodontics, or historically, tooth pulling) is the removal of teeth from the dental alveolus (socket) in the alveolar bone. Extractions are performed for a wide variety of reasons, but most commonly to remove teeth which have become unrestorable through tooth decay, periodontal disease or dental trauma; especially when they are associated with toothache. Sometimes wisdom teeth are impacted (stuck and unable to grow normally into the mouth) and may cause recurrent infections of the gum (pericoronitis). In orthodontics if the teeth are crowded, sound teeth may be extracted (often bicuspids) to create space so the rest of the teeth can be straightened.
Tooth extraction is usually relatively straightforward, and the vast majority can be usually performed quickly while the individual is awake by using local anesthetic injections to eliminate painful sensations. Local anesthetic blocks pain, but mechanical forces are still vaguely felt. Some teeth are more difficult to remove for several reasons, especially related to the tooth’s position, the shape of the tooth roots and the integrity of the tooth.Dental phobia is an issue for some individuals, and tooth extraction tends to be feared more than other dental treatments like fillings. If a tooth is buried in the bone, a surgical or trans alveolar approach may be required, which involves cutting the gum away and removal of the bone which is holding the tooth in with a surgical drill. After the tooth is removed, stitches are used to replace the gum into the normal position.
Immediately after the tooth is removed, a bite pack is used to apply pressure to the tooth socket and stop the bleeding. After a tooth extraction, dentists usually give advice which revolves around not disturbing the blood clot in the socket by not touching the area with a finger or the tongue, by avoiding vigorous rinsing of the mouth and avoiding strenuous activity. Sucking, such as through a straw, is to be avoided. If the blood clot is dislodged, bleeding can restart, or alveolar osteitis (“dry socket”) can develop, which can be very painful and lead to delayed healing of the socket. Smoking is avoided for at least 24 hours as it impairs wound healing and makes dry socket significantly more likely. Most advise hot salt water mouth baths which start 24 hours after the extraction.
Reasons for Extractions
The most common reason for extraction is tooth damage due to breakage or decay. There are additional reasons for tooth extraction:
- Severe tooth decay or infection (acute or chronic alveolar abscess). Despite the reduction in worldwide prevalence of dental caries, it is still the most common reason for extraction of (non-third molar) teeth with up to two thirds of extractions.
- Supernumerary teeth which are blocking other teeth from coming in.
- Severe gum disease which may affect the supporting tissues and bone structures of teeth.
- In preparation for orthodontic treatment (braces)
- Teeth in the fracture line
- Teeth which cannot be restored endodontically
- Fractured teeth
- Supernumerary, supplementary or malformed teeth
- Prosthetics; teeth detrimental to the fit or appearance of dentures
- Treatment of symptomatic impacted wisdom teeth, whose impaction is causing pathosis that will lead to yet more (infection, inflammation, bone resorption)
- Preventive/prophylactic removal of asymptomatic impacted wisdom teeth. Although many dentists remove asymptomatic impacted third molars, both American and British Health Authorities recommend against this routine procedure, unless there are evidences for disease in the impacted tooth or the near environment. The American Public Health Association, for example, adopted a policy, Opposition to Prophylactic Removal of Third Molars (Wisdom Teeth) because of the large number of injuries resulting from unnecessary extractions.
- Cosmetic; teeth of poor appearance, unsuitable for restoration
- Receiving radiation therapy to the head and neck area may require extraction of teeth in the field of radiation.
- Deliberate, medically unnecessary, extraction as a form of physical torture.
- It was once a common practice to remove the front teeth of institutionalized psychiatric patients who had a history of biting.
- Reduced cost compared to other treatments
Complications and Risks for Extractions
- Infection: The dentists may opt to prescribe antibiotics pre- and/or post-operatively if they determine the patient to be at risk.
- Prolonged bleeding: The dentist has a variety of means at their disposal to address bleeding; however, small amounts of blood mixed in the saliva after extractions are normal, even up to 72 hours after extraction. Usually, however, bleeding will almost completely stop within eight hours of the surgery, with only minuscule amounts of blood mixed with saliva coming from the wound. A gauze compress will significantly reduce bleeding over a period of a few hours.
Swelling: Often dictated by the amount of surgery performed to extract a tooth (e.g. surgical insult to the tissues both hard and soft surrounding a tooth). Generally, when a surgical flap must be elevated (i.e. and the periosteumcovering the bone is thus injured), minor to moderate swelling will occur. A poorly cut soft tissue flap, for instance, where the periosteum is torn off rather than cleanly elevated off the underlying bone, will often increase such swelling. Similarly, when bone must be removed using a drill, more swelling is likely to occur.
Bruising: Bruising may occur as a complication after tooth extraction. Bruising is more common in older people or people on aspirin or steroid therapy. It may take weeks for bruising to disappear completely.
- Sinus exposure and oral-antral communication: This can occur when extracting upper molars (and in some patients, upper premolars). The maxillary sinus sits right above the roots of maxillary molars and premolars. There is a bony floor of the sinus dividing the tooth socket from the sinus itself. This bone can range from thick to thin from tooth to tooth from patient to patient. In some cases it is absent and the root is in fact in the sinus. At other times, this bone may be removed with the tooth, or may be perforated during surgical extractions. The doctor typically mentions this risk to patients, based on evaluation of radiographs showing the relationship of the tooth to the sinus. The sinus cavity is lined with a membrane called the Sniderian membrane, which may or may not be perforated. If this membrane is exposed after an extraction, but remains intact, a “sinus exposed” has occurred. If the membrane is perforated, however, it is a “sinus communication”. These two conditions are treated differently. In the event of a sinus communication, the dentist may decide to let it heal on its own or may need to surgically obtain primary closure—depending on the size of the exposure and the likelihood of the patient to heal. In both cases, a resorbable material called “gelfoam” is typically placed in the extraction site to promote clotting and serve as a framework forgranulation tissue to accumulate. Patients are typically provided with prescriptions for antibiotics that cover sinus bacterial flora, decongestants, and careful instructions to follow during the healing period.
- Nerve injury: This is primarily an issue with extraction of third molars, but can occur with the extraction of any tooth should the nerve be close to the surgical site. Two nerves are typically of concern, and are found in duplicate (one left and one right): 1. the inferior alveolar nerve, which enters the mandible at the mandibular foramen and exits the mandible at the sides of the chin from the mental foramen. This nerve supplies sensation to the lower teeth on the right or left half of the dental arch, as well as sense of touch to the right or left half of the chin and lower lip. 2. The lingual nerve (one right and one left), which branches off the mandibular branches of the trigeminal nerve and courses just inside the jaw bone, entering the tongue and supplying sense of touch and taste to the right and left half of the anterior 2/3 of the tongue as well as the lingual gingiva (i.e. the gums on the inside surface of the dental arch). Such injuries can occur while lifting teeth (typically the inferior alveolar), but are most commonly caused by inadvertent damage with a surgical drill. Such injuries are rare and are usually temporary, but depending on the type of injury (i.e. Seddon classification: neuropraxia, axonotmesis, & neurotmesis), can be prolonged or even permanent.
- Displacement of tooth or part of the tooth into the maxillary sinus (upper teeth only). In such cases, the tooth or tooth fragment must almost always be retrieved. In some cases, the sinus cavity can be irrigated with saline (antral lavage) and the tooth fragment may be brought back to the site of the opening through which it entered the sinus, and may be retrievable. At other times, a window must be made into the sinus in the Canine fossa—a procedure referred to as a “Caldwell-Luc”.
- Dry socket (Alveolar osteitis) is a painful phenomenon that most commonly occurs a few days after the removal of mandibular (lower) wisdom teeth. It typically occurs when the blood clot within the healing tooth extraction site is disrupted. More likely,alveolar osteitis is a phenomenon of painful inflammation within the empty tooth socket because of the relatively poor blood supply to this area of the mandible (which explains why dry socket is usually not experienced in other parts of the jaws). Inflamed alveolar bone, unprotected and exposed to the oral environment after tooth extraction, can become packed with food and debris. A dry socket typically causes a sharp and sudden increase in pain commencing 2–5 days following the extraction of a mandibular molar, most commonly the third molar. This is often extremely unpleasant for the patient; the only symptom of dry socket is pain, which often radiates up and down the head and neck. A dry socket is not an infection, and is not directly associated with swelling because it occurs entirely within bone – it is a phenomenon of inflammation within the bony lining of an empty tooth socket. Because dry socket is not an infection, the use of antibiotics has no effect on its rate of occurrence. There is some evidence that rinsing with chlorhexidine before or after extraction or placing chlorhexidine gel in the sockets of extracted teeth provides a benefit in preventing dry socket, but potential adverse effects of chlorhexidine have to be considered. The risk factor for alveolar osteitis can dramatically increase with smoking after an extraction.
- Bone fragments: Particularly when extraction of molars is involved, it is not uncommon for the bones which formerly supported the tooth to shift and in some cases to erupt through the gums, presenting protruding sharp edges which can irritate the tongue and cause discomfort. This is distinguished from a similar phenomenon where broken fragments of bone or tooth left over from the extraction can also protrude through the gums. In the latter case, the fragments will usually work their way out on their own. In the former case, the protrusions can either be snipped off by the dentist, or eventually the exposed bone will erode away on its own.
- Trismus: Trismus, also known as lockjaw, affects functions of the oral cavity by restricting opening of the mouth. A double blind, clinical study was done to test the effect of two different medications on post-extraction trismus. The patients who received a corticosteroid by IV had a statistically significant lower level of trismus when compared to patients receiving an NSAID by IV or no medication.
- Loss of a tooth: If an extracted tooth slips out of the forceps, it may be swallowed or inhaled. The patient may be aware of swallowing it, or they may cough, which suggests inhalation of the tooth. The patient must be referred to for a chest Xray in hospital if a tooth cannot be found. If it has been swallowed, no action is necessary as it usually passes through the alimentary canal without doing any harm. But if it has been inhaled, an urgent operation is necessary to recover it from the airway or lung before it causes serious complications such as pneumonia or a lung abscess.
- Luxation of the adjacent tooth: The force application during extraction procedure must strictly be limited to the tooth that requires the extraction. Most case of surgical extraction procedures require that the forces are diverted from the tooth itself to areas such as bone surrounding the tooth to ensure adequate bone removal before proceeding any further in the extraction procedure. Either ways the forces applied by various instruments during both simple and complicated surgical procedure may loosen the teeth present both in-front or behind of the tooth depending upon the impact, direction and location of the force being applied, and that happening only if the forces divert from the actual tooth that needs extraction. Such deleterious forces may weaken the anchorage of adjacent teeth from within their boney socket and hence result in weakening of the adjacent teeth.
- Extraction of the wrong tooth: Misdiagnosis, altered tooth morphology, faulty clinical examination, poor patient history, undetected / unmentioned previous extractions that may predispose the operator to consider another tooth to be a replicate of the one previously extracted are a few causes of extraction of a wrong tooth.
- Osteonecrosis: Osteonecrosis of the jaw is the slow destruction of bone in an extraction site. A case control study of 191 cases and 573 controls were used to understand the relationship between osteonecrosis of the jaw and bispohosponate usage prior to tooth extraction. All of the participants were over 40 years of age, mostly female, and had been taking bisphosphonates for six months or longer. The presence of osteonecrosis of the jaw was reported by dentists’ previous diagnosis of the participating case and control patient’s medical records. Reports showed that women using bisphosphonates for more than two years are ten times more likely to experience osteonecrosis of the jaw, while women who have taken bisphosphonates for less than two years are four times more likely to suffer from osteonecrosis of the jaw when compared to women who were not taking bisphosphonates. Therefore, it is extremely important to report all medications used to the dentist before an extraction, so that osteonecrosis can be avoided.