the magnitude of the defect, and the amount of soft tissue available to support the bone segment if maintained. If the surgeon has been supporting the alveolus with finger pressure during extraction, early cortical plate fracture can be assessed. At this point, the cortical plate should be dissected free from the tooth with an elevator or other sharp instrument while the tooth is stabilized with forceps. Once the bone and soft tissue are dissected free, the tooth is extracted and the tissues approximated and secured with sutures. If a soft tissue flap is reflected from bone, the blood supply to the segment has been compromised, and if not removed, that segment will become necrotic. Maxillary tuberosity fractures should be treated in a similar manner. Once recognized, the fractured segment should be dissected free from the tooth. Using a handpiece, the bone segment can be separated from the tooth and the roots sectioned to allow for atraumatic extraction. If adequate soft tissue attachment (periosteum) remains, the tuberosity is stabilized through good soft tissue closure with sutures. In the event that the tuberosity cannot be dissected free from the tooth, the primary reason for extraction should be reevaluated. If asymptomatic, the tooth and attached tuberosity segment can be fixated for six to eight weeks via arch bar or orthodontic fixation followed by surgical extraction with controlled bone removal and tooth sectioning on a later date. If symptomatic, the tooth must be extracted, and in doing so, the tuberosity will be removed. The remaining bone should be smoothened and the soft tissues should be approximated with sutures. The overall goal of treatment in tuberosity fractures is to maintain the bone in place unless its removal is deemed absolutely necessary [3, 22].
Fig. 2.4. Fractured tuberosity with extraction of second molar.
Pain and Swelling
Etiology: surgical trauma, duration of surgery
Management: good surgical technique, steroids, analgesics, local anesthesia
Postoperative pain and swelling following third molar surgery are an expected and inevitable consequence of the inflammatory process of healing. The onset of swelling and pain is directly related to an increase in local levels of prostaglandins, leukotrienes, and thromboxane A2. Pain usually reaches its peak in three to five hours following surgery. On the other hand, edema reaches its peak in 24–48 hours, and then generally begins to decline on postoperative day 3 or 4. Contributing factors in the development of pain and swelling include increased operating time, difficulty in extraction, excessive retraction, surgeon experience, and the degree of surgical trauma [3, 4].
“Treatment” of swelling and pain can begin prophylactically prior to surgery. Preoperative IV steroids have been shown in multiple studies to decrease postoperative edema and pain, and improve health‐related quality of life [23]. During surgery, good surgical technique, copious irrigation, and the use of long‐lasting local anesthetics such as bupivacaine have been shown to decrease pain and swelling. Postoperative scheduled use of nonsteroidal anti‐inflammatory drugs (NSAIDs) has been shown more effective in pain reduction than narcotic medications, and as such, narcotics are more appropriately reserved for breakthrough pain [3, 4].
TMJ Injury
Etiology: excessive force, poor support of the mandible
Management: bite block use, avoid excessive mouth opening or force, arthrocentesis
The occurrence of temporomandibular joint (TMJ) injury as a result of third molar surgery is not supported in the literature. In a study by Threlfall et al., patients with diagnosed anterior disc displacement were no more likely than the control group to have had prior third molar surgery [24]. Also, only 9.5% of patients with anterior disc displacement reported third molar extractions within the last five years. Complaints of limited mouth opening are most often due to trauma from local anesthetic injections, inflammation of the muscles of mastication, and/or the body's own protective mechanism to limit function and further trauma [24].
Injury may occur if excessive force is used, a bite block is not in place when extracting lower third molars, or the patient's mouth is opened excessively [4, 24]. This transient injury often resolves with soft diet, moist heat, jaw rest, and NSAID use. An acutely “stuck disc” can be treated effectively with TMJ arthrocentesis when observed [24].
It is important to evaluate all patients undergoing third molar surgery for preoperative TMJ disease or myofascial pain, and thoroughly document any such history. TMJ clicks, pops, crepitus, opening and excursive movements, and any tenderness of the muscles of mastication should be noted. If prior TMJ dysfunction is present, contemplation for surgical extraction of teeth to avoid trauma to the TMJ should be considered.
Displacement of Teeth
Etiology: patient anatomy, excessive force
Management: removal of displaced teeth in an immediate or delayed fashion, monitoring
The iatrogenic displacement of maxillary and mandibular third molars into adjacent spaces is a rare complication with an unknown incidence [25]. Maxillary third molars can be displaced into the maxillary sinus, buccal vestibule, or posteriorly through periosteum and into the infratemporal fossa [3, 4] (Figure 2.5a and b). Contributing factors for the displacement of maxillary third molars include deep impactions, distoangular impactions, poor visualization and access, inadequate bone removal, lack of a distal stop, and careless elevation [25]. Displacement of mandibular third molars into the submandibular, sublingual, pterygomandibular, and even lateral pharyngeal spaces has been reported along with displacement of roots into the inferior alveolar canal (IAC) [3, 4] (Figure 2.6a–c). The lingual cortex becomes progressively thinner from anterior to posterior in the mandible, and this often results in an extremely thin or even a dehiscence of the lingual plate. Any apically directed forces can easily displace root segments, or an entire tooth, into the aforementioned spaces [3].
Fig. 2.5. (a) Tooth #1 displaced into the maxillary sinus during extraction – panoramic image. (b) Tooth #1 displaced into the maxillary sinus – 3D reconstruction.
Fig. 2.6. (a) CT axial view at the level of the third molars demonstrating tooth #32 displaced into the submandibular space. (b, c) Coronal view CBCT demonstrating mandibular third molar root tips in close approximation to the submandibular space and high risk for displacement.
The management of a displaced third molar tooth or root varies depending upon the space involved. Maxillary third molars displaced into the maxillary sinus should be removed. Root tips <3 mm can be left to fibrose into the sinus mucosa if no previous infection of the tooth or sinus is present and initial attempts at retrieval are unsuccessful [3]. The morbidity of additional surgical procedures outweighs the benefits of removal in this case. An attempt to remove the tooth through the socket can be made by placing the suction