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.
Procedure Extractions could be categorized into non-surgical (simple) and surgical, depending on the type of tooth to be removed and other factors.
Assessment and special investigations A comprehensive history taking should be performed to find out the pain history of the tooth, the patient's medical history and the history of previous difficult extractions. The tooth should be assessed clinically i.e. checked visually by the dentist. Pre-extraction radiographs are not always necessary but are often taken to confirm the diagnosis and hence appropriate treatment plan. Radiographs also help in visualising the shape and size of roots which are beneficial in planning the extraction. All this information will aid the dentist in foreseeing any difficulties and hence preparing appropriately.
Obtaining consent from patient In order to obtain permission from patient for extraction of tooth, the dentist should explain that other treatment options are available, what is involved in the dental extraction procedure, the potential risks of the procedure and the benefits of the procedure. The process of gaining consent should be documented in clinical notes.
Giving local anaesthetic Before extracting a tooth, the dentist would deliver local anaesthetic to ensure the tooth and surrounding tissues are numb before they start the extraction. There are several techniques to achieve numbness of the tooth including
infiltration – injection containing local anaesthetic is delivered into the gum near the root tip of the tooth to be extracted. This allows the local anaesthetic to penetrate through the bone, eventually reaching the nerve bundle of the tooth to be extracted. nerve block – injection containing local anaesthetic is delivered to an earlier branch of a nerve. For example, the inferior alveolar nerve block can be used to anaesthetise all the lower teeth.
The two most commonly used local anaesthetics in the UK are lidocaine and articaine. Prior to injection, topical anaesthetic gel or cream, such as lidocaine or benzocaine, can be applied to the gum to numb the site of the injection up to a few millimetres deep. This should reduce the discomfort felt during the injection and thus help to reduce patient anxiety.
Removal of tooth During extraction, multiple instruments are used to aid and ease the removal of the tooth whilst trying to minimally traumatise the tissues to allow for quicker healing. Extraction forceps are commonly used to remove teeth. Different shaped forceps are available depending on the type of tooth requiring removal, what side of the mouth (left or right) it is on and if it is an upper or lower tooth. The beaks of the forceps must grip onto the root of the tooth securely before pressure is applied along the long axis of the tooth towards the root.
Different movements of the forceps can be employed to remove teeth. Generally, while keeping downwards pressure attempts to move the tooth towards the cheek side (buccal) and then the opposite direction (palatal or lingual) are made to loosen the tooth from its socket. For single, conical-rooted teeth such as the incisors, rotatory movements are also used. A 'figure of eight' movement can be used to extract lower molars.
Instruments used are summarised below: +NameType of instrumentUseArea of useUnique featuresLuxatorLuxatorTear PDL around tooth AnywhereSharp bladeCouplandElevatorexpand socket and lift AnywhereNumbered 1–3 from most narrow to wideWarrick JamesElevatorExpand socket and lift toothAnywhereRight left and straight CryersElevatorExpand socket and lift toothAnywhereRight and left with sharp tipsUpper straightForcepsRemove teethUpper canine to canineStraight handleUpper anteriorForcepsRemove teethUpper anteriors and premolarsUpper molarForcepsRemove teethUpper 1st/2nd/3rd molarsOne pointed end to engage buccal furcationUpper bayonetForcepsRemove teethUpper 3rd molarsCurved handle and tip to reach 3rd molarsUpper rootForcepsRemove teethUpper retained/fractured rootsNarrow tipsCowhornForcepsRemove teethLower molarsThin tips to engage furcation of broken down molarsLower anteriorForcepsRemove teethLower anteriors and premolars90 degree bend handlelower molarForcepsRemove teethLower 1st/2nd/3rd molars2 beak tips to engage furcationsLower rootForcepsRemove teethLower retained/fractured rootsNarrow tips to engage roots
In terms of operator positioning when removing a tooth, the patient is placed more supine when extracting an upper and more upright when extracting a lower. This is to allow direct vision for the operator during the procedure. A right handed operator will stand to the front of the patient and to their right when removing any upper teeth or lower left teeth. However, they will stand behind the patient and to the right when extracting a lower right tooth.
Dental elevators can be used to aid removal of teeth. Various types are available that have different shapes. Their working ends are designed to engage into the space between the tooth and bone of the socket. Rotatory movements are then made to dislodge the tooth from the socket. Another similar looking but sharper instrument that can be used is a luxator; this instrument can be used gently and with great care to cut the ligament between the tooth and its boney socket (periodontal ligament).
Achieving haemostasis Biting down on a piece of sterile gauze over the socket will provide firm pressure to the wound. Normally this is sufficient to stop any bleeding and will promote blood clot formation at the base of the socket.
Moreover, the patient must be inhibited from eating and drinking hot food in the first 24 hours. Using straw for drinking is also prohibited due to the negative pressure it can produce which will lead to removal of a newly formed clot from the socket.
The source of any bleeding can either be from soft tissues (gingiva and mucosa) or hard tissue (the bony socket). Bleeding of soft tissues can be controlled by several means including suturing the wound (stitches) and/ or using chemical agents such as tranexamic acid, ferric sulphate and silver nitrate. Bony bleeding can be arrested by using haemostatic gauze and bone wax. Other means of achieving haemostasis include electrocautery.
Reasons
Medical/Dental
Severe tooth decay or infection (acute or chronic alveolar abscess, such as periapical abscess – collection of infected material [pus] forming at the tip of the root of a tooth). Despite the reduction in worldwide prevalence of dental caries, it is still the most common reason for extraction of (non-third molar) teeth, accounting for up to two thirds of extractions. Severe gum disease, which may affect the supporting tissues and bone structures of teeth. Treatment of symptomatic impacted wisdom teeth e.g. that are associated with pericoronitis, unrestorable caries or cysts. Prophylactic removal of asymptomatic impacted wisdom teeth. Historically, many asymptomatic impacted third molars were removed, however, both American and British Health Authorities now provide guidance about the indication for third molar removal. 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. Supernumerary teeth that are blocking other teeth from coming in. Supplementary or malformed teeth. Fractured teeth. Teeth in the fracture line of the jaw bone Teeth which cannot be restored endodontically. Prosthetics; teeth detrimental to the fit or appearance of dentures. Head and neck radiation therapy, to treat and/or manage tumors, may require extraction of teeth, either before or after radiation treatments. Lower cost, compared to other treatments. 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.
Orthodontic
In preparation for orthodontic treatment (braces). Extractions are commonly required before the provision of orthodontic treatment, to create space for crowded teeth to be moved into. The premolar teeth are the most commonly extracted teeth for this purpose.
Aesthetics
Cosmetic: to remove teeth of poor appearance, unsuitable for restoration.
Types
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. Surgical extractions almost always require an incision. In a surgical extraction the dentist may elevate the soft tissues covering the tooth and bone, and may also remove some of the overlying and/or surrounding jaw bone with a drill or, less commonly, an instrument called an osteotome. Frequently, the tooth may be split into multiple pieces to facilitate its removal.
Common risks after any extraction include pain, swelling, bleeding, bruising, infection, trismus (not being able to open as wide as normal) and dry socket. There are additional risks associated with the surgical extraction of wisdom teeth in particular: permanent or temporary damage to the inferior alveolar nerve +/− lingual nerve, causing permanent or temporary numbness, tingling or altered sensation to the lip, chin +/− tongue.
Surgical procedure 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.
Pre-extraction consideration