Dental extraction

Operation to remove a tooth

A dental extraction (also referred to as tooth extraction, exodontia, exodontics, or informally, 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 impacted wisdom teeth (wisdom teeth that are stuck and unable to grow normally into the mouth) cause recurrent infections of the gum (pericoronitis), and may be removed when other conservative treatments have failed (cleaning, antibiotics and operculectomy). In orthodontics, if the teeth are crowded, healthy teeth may be extracted (often bicuspids) to create space so the rest of the teeth can be straightened.

Extractions could be categorized into non surgical (simple) and surgical, depending on the type of tooth to be removed and other factors.

Extractions are often categorized as "simple" or "surgical". Simple extractions are performed on teeth that are visible in the mouth, usually with the patient under local anaesthetic, and require only the use of instruments to elevate and/or grasp the visible portion of the tooth. Typically the tooth is lifted using an elevator, and using dental forceps, specific tooth movements are performed (e. g. rocking the tooth back and forth) expanding the tooth socket. Once the periodontal ligament is broken and the supporting alveolar bone has been adequately widened the tooth can be removed. Typically, when teeth are removed with forceps, slow, steady pressure is applied with controlled force. Surgical extractions involve the removal of teeth that cannot be easily accessed or removed via simple extraction, for example because they have broken under the gum or because they have not erupted fully, such as an impacted wisdom tooth.

Incisions are made full thickness through mucosa and periosteum to bone. In general, the flap is extended from one tooth behind the tooth concerned to one tooth in front, including the interdental papilla. An anterior relieving incision is made extending down into the sulcus. This flap design is called “two sided”. A “three sided” flap includes an additional relieving incision posteriorly. The flap is raised using periosteal elevator to expose the area of interest. The flap is held out of the way with an instrument such as a rake retractor. A small gutter of bone is drilled away around the tooth to make space into which an application point for instruments can be achieved. It is important that copious amount of saline is used to cool the bone during this process. The tooth concerned can be removed using a combination of luxators, elevators and extraction forceps. Any sharp bone is smoothed off and the wound is irrigated with saline. The flap is repositioned and sutured in place.

Immediately following the removal of a tooth, bleeding or oozing very commonly occurs. Pressure is applied by the patient biting on a gauze swab, and a thrombus (blood clot) forms in the socket (hemostatic response). Common hemostatic measures include local pressure application with gauze, and the use of oxidized cellulose (gelfoam) and fibrin sealant. Dental practitioners usually have absorbent gauze, hemostatic packing material (oxidized cellulose, collagen sponge), and suture kit available. Sometimes 30 minutes of continuous pressure is required to fully arrest bleeding.

Talking, which moves the mandible and hence removes the pressure applied on the socket, instead of keeping constant pressure, is a very common reason that bleeding might not stop. This is likened to someone with a bleeding wound on their arm, when being instructed to apply pressure, instead holds the wound intermittently every few moments. Coagulopathies (clotting disorders, e. g. hemophilia) are sometimes discovered for the first time if a person has had no other surgical procedure in their life, but this is rare. Sometimes the blood clot can be dislodged, triggering more bleeding and formation of a new blood clot, or leading to a dry socket (see complications). Some oral surgeons routinely scrape the walls of a socket to encourage bleeding in the belief that this will reduce the chance of dry socket, but there is no evidence that this practice works. The most serious post extraction healing complication is that slow or halted healing caused by the adverse effects of use of bisphosphonates which can cause osteochemonecrosis of the bone.

The chance of further bleeding reduces as healing progresses, and is unlikely after 24 hours. The blood clot is covered by epithelial cells which proliferate from the gingival mucosa of socket margins, taking about 10 days to fully cover the defect. In the clot, neutrophils and macrophages are involved as an inflammatory response takes place. The proliferative and synthesizing phase next occurs, characterized by proliferation of osteogenic cells from the adjacent bone marrow in the alveolar bone. Bone formation starts after about 10 days from when the tooth was extracted. After 10–12 weeks, the outline of the socket is no longer apparent on an X ray image. Bone remodeling as the alveolus adapts to the edentulous state occurs in the longer term as the alveolar process slowly resorbs. In maxillary posterior teeth, the degree of pneumatization of the maxillary sinus may also increase as the antral floor remodels.

Post operative instructions following tooth extractions can be provided to encourage healing of the socket and prevent post operative complications from arising. The advice listed below is usually given verbally, and can be supplemented with instructions in the written form. The combination of both methods of delivery has been found to reduce the severity of pain experienced by patients post extraction and results in higher levels of patient satisfaction compared to verbal post operative instructions alone.

Socket preservation or alveolar ridge preservation (ARP) is a procedure to reduce bone loss after tooth extraction to preserve the dental alveolus (tooth socket) in the alveolar bone. At the time of extraction a platelet rich fibrin (PRF) membrane containing bone growth enhancing elements is placed in the wound or a graft material or scaffold is placed in the socket of the extracted tooth.

1. Primary prolonged bleeding

This type of bleeding occurs during/immediately after extraction, because true haemostasis has not been achieved. It is usually controlled by conventional techniques, such as applying pressure packs or haemostatic agents onto the wound. 2. Reactionary bleeding

This type of bleeding starts 2 to 3 hours after tooth extraction, as a result of cessation of vasoconstriction. Systemic intervention might be required. 3. Secondary bleeding

This type of bleeding usually begins 7 to 10 days post extraction, and is most likely due to infection destroying the blood clot or ulcerating local vessels.

There is no clear evidence from clinical trials comparing the effects of different interventions for the treatment of post extraction bleeding.

Infection: The dentist may opt to prescribe antibiotics pre and/or post operatively if he or she determines the patient to be at risk of infection. Prolonged bleeding: The dentist has a variety of means at his/her disposal to address bleeding; however, small amounts of blood mixed in the saliva after extraction 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., the periosteum covering 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, possibly leading to infection, and oral antral communication: This can occur when extracting upper molars (and in some patients, upper premolars). The maxillary sinus sits directly 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 extraction. 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 for granulation 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 jaw). Inflamed alveolar bone, unprotected and exposed to the oral environment after tooth extraction, can become packed with food and debris. 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. Maxilla tuberosity fracture: Can occur especially during molar extractions. There can be a variety of factors causing this including single standing molar, extracting in the wrong order, inadequate alveolar support, pathological gemination or extension of maxillary sinus weakening the area. 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 for a chest X ray 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.

Atraumatic extraction is a novel technique for extracting teeth with minimal trauma to the bone and surrounding tissues. It is especially useful in patients who are highly susceptible to complications such as bleeding, necrosis, or jaw fracture. It can also preserve bone for subsequent implant placement. Techniques involve minimal use of forceps, which damage socket walls, relying instead on luxators, elevators and syndesmotomy.

Following dental extraction, a gap is left. The options to fill this gap are commonly recorded as Bind, and the choice is made by dentist and patient based on several factors. Treatment option Advantages Disadvantages Bridge Fixed to adjacent teeth Drilling usually required on one or both sides of the gap if conventional bridge (average lifespan about 10 years). Conservative bridge (average lifespan about 5 years) preparation may cause minimal damage to adjacent teeth. Expensive and complex treatment, not suited to all situations, e. g., large gaps in the back of the mouth Alveolar bone will still resorb, and eventually a gap may show under bridge. Implant Fixed to jawbone. Maintains alveolar bone, which would otherwise undergo resorption. Usually a long term lifespan. Expensive and complex, requiring specialist. May involve other procedures such as bone grafting. Relatively contra indicated in tobacco smokers. Denture Often a simple, quick, and relatively cheap treatment compared to bridge and implant. Not usually any drilling of other teeth required. It is far easier to replace several teeth with a denture than place multiple bridges or implants. Denture is not fixed in mouth. Over time worsens periodontal disease unless there is good level of oral hygiene, and may damage soft tissues. Potential for slightly accelerated resorption of alveolar bone compared to no denture. Potential for poor tolerance in persons with over sensitive gag reflex, xerostomia, etc. Nothing (i. e., not replacing the missing tooth) Often the choice due to cost of other treatment or lack of motivation for other treatments. Part of a shortened dental arch plan, which revolves around the fact that not all teeth are required to eat comfortably, and only the incisors and premolars need be preserved for normal function. This is usually the choice taken if the reason of dental extraction is due to impacted wisdom teeth or orthodontics because of limited space. The alveolar bone will slowly resorb over time once the tooth is lost. Potential esthetic concern. Potential for drifting and rotation of adjacent teeth into the gap over time.

Historically, dental extractions have been used to treat a variety of illnesses. Before the discovery of antibiotics, chronic tooth infections were often linked to a variety of health problems, and therefore removal of a diseased tooth was a common treatment for various medical conditions. Instruments used for dental extractions date back several centuries. In the 14th century, Guy de Chauliac invented the dental pelican, which was used through the late 18th century. The pelican was replaced by the dental key which, in turn, was replaced by modern forceps in the 19th century. As dental extractions can vary tremendously in difficulty, depending on the patient and the tooth, a wide variety of instruments exist to address specific situations. Rarely, tooth extraction was used as a method of torture, e. g., to obtain forced confessions.