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The fracture of the body of the mandible accounts for almost 11% to 36% of all the mandibular fractures. This activity describes the evaluation and management of fracture, mandible body, and highlights the role of the interprofessional team in evaluating and treating patients with this condition. Objectives: Describe the pathophysiology of fracture of the mandible body. Outline the presentation of a patient with fracture of mandible body. Explain the management considerations for patients with fractures of the mandible body. Summarize the importance of collaboration and communication amongst the interdisciplinary team to improve outcomes for patients affected by fracture, mandible body. Access free multiple choice questions on this topic.

Fracture of the mandible accounts for approximately 25% of maxillofacial fractures.[1] Among the different mandibular fractures, the fracture of the body of the mandible accounts for almost 11% to 36%, with personal violence as the principal factor.[2]

The etiology of body fractures includes personal violence/assault, vehicular accidents, falls, and sports activities.[2][1] Among all the factors, vehicular accidents are the most common cause (43%), followed by assaults (34%), falls (7%), and sporting accidents (4%).

Various studies have reported that among mandibular fractures, mandibular body fractures account for almost 29% (range 11-36%), followed by the condyle and angle. In children, condylar and body fractures have been demonstrated to be the most prevalent maxillofacial fractures.[3] Body fractures are more prevalent among males than females.[1]

Mandibular body fractures usually occur between the distal aspect of the canine and a hypothetical line that corresponds to the region of anterior attachment of the masseter muscle. They may be classified based on anatomic location, fracture line direction, tooth position relative to the fracture, and fracture favorability.[4][5] Based on the fracture line direction and the effect of muscle distraction on the fracture fragments, the body fractures can be classified into 2 types (favorable and unfavorable). In favorable fractures, the bony fragments are drawn together by the muscle distraction, whereas in unfavorable fractures, the bony segments become displaced by the muscle forces. The forces that render the fracture unfavorable are exerted by various muscles, such as the masseter, temporalis, and medial pterygoid. These muscles distract the proximal bony segment in the superomedial direction. Moreover, 2 additional muscles (mylohyoid and the anterior belly of the digastrics) may also contribute to posterior and inferior displacement of the segments.

History: A thorough history of the patient that includes any preexisting systemic bone disease, neoplasia affecting the bone, arthritis, collagen vascular disorders, and temporomandibular joint dysfunction must merit consideration. The nature of the injury and the presence of any additional fractures is assessable by the type and direction of the causative traumatic force. The vehicular accidents tend to have a larger magnitude of force that may result in multiple, compound, comminuted mandibular fractures compared to assaults that may result in a single, simple, nondisplaced fracture. Physical: Intraorally, a change in occlusion may be apparent on physical examination. There may be anesthesia, paresthesia, or dysesthesia of the lower lip. This change in lower lip sensation generally occurs in displaced body fractures that are distal to the mandibular foramen (along with the distribution of the inferior alveolar nerve) and not seen in nondisplaced mandible fractures.[6][7] In general, the common signs of a body fracture include laceration in the gingiva, step defect in the occlusion, and/or ecchymosis in the floor of the mouth. Ecchymosis on the floor of the mouth is a pathognomonic sign of a mandibular body fracture. The examiner should note the mobility in the fracture. To do so, use both hands to manipulate the mandible by placing the thumb on the occlusal surface of the teeth and fingers on the inferior border of the mandible. Then, slowly and carefully, pressure should be placed between the 2 hands.[6][7] Extraorally, there may be a change in facial contour due to loss of external mandibular form and skin abrasion. A body fracture often results in a flattened appearance of the face's lateral aspect. On palpation, there is a loss of the mandibular body. An unfavorable fracture should be suspected. The anterior face may be displaced forward, resulting in elongation. In such cases, the anterior mandible becomes displaced in the downward direction. Other findings include lacerations, hematoma, and ecchymosis.

Evaluation of the body fracture is via radiographs using plain radiography (panoramic, lateral-oblique, posteroanterior, occlusal, and periapical views) and computed tomography scan. The lateral-oblique view helps to diagnose posterior body fractures. Mandibular occlusal view and Caldwell posteroanterior view demonstrate the presence of medial or lateral displacement of body fractures. Among all the radiographs, the most informative is the panoramic radiograph. The entire mandible is viewable in a single plane, with advantages such as simplicity of technique, cost-effectiveness, and lower radiation exposure compared with computed tomography or cone-beam computed tomography (CBCT). However, it is challenging to take a panoramic radiograph in a severely traumatized patient as it usually requires the patient to be upright position. Also, as it is a 2-dimensional image, it becomes difficult to appreciate buccolingual bone displacement. When conventional 2-dimensional radiographs cannot provide an accurate picture of the fracture, CBCT can be useful, as it is highly sensitive in identifying fractures. Also, it provides better image quality and reduces the risk of interpretation errors.[7][8]

There are 2 methods for treating mandibular body fractures: non-surgical conservative management and surgical management. Whether to treat the fracture with surgical or non-surgical means depends on its type, severity, and consequences. In non-surgical management, also known as closed reduction, maxillomandibular fixation (MMF) stabilizes the fracture.[9] It offers various advantages, such as being low-cost (it does not require any surgical treatment or hospitalization), being a less invasive procedure, and having low sensitivity to professional experience. However, MMF should not occur in a non-compliant patient, a patient with seizure disorders, severe pulmonary dysfunction, intellectual disability, psychosis, pregnancy, or multiple system injuries. Indications for closed reduction include: Non-displaced favorable fractures Presence of healthy dentition with sufficient teeth to obtain a stable occlusion Grossly comminuted fractures Edentulous fractures Fractures in children with developing dentition Presence of adequate occlusion Good facial esthetics and adequate open mouth The procedure involves placing Ivy loops with 24-gauge wire between 2 stable teeth, followed by a smaller-gauge wire to provide MMF between the Ivy loops. Arch bars with 24- and 26-gauge wires are also frequently used. The arch bar provides additional stability through a tension-banding mechanism, creating a second line of resistance. While placing arch bars, at least all the teeth in the affected quadrant of the mandible should be included. Encompassing the whole dental arch is not necessary. Arch bars are easy to place, have low cost, restore normal occlusion, and reduce the distraction of bone at the healing site. However, they require a second procedure for their removal and provide only semirigid fixation. In the case of an edentulous mandible, dentures can be wired to the jaw using circummandibular wires. But it has some disadvantages, including postoperative discomfort due to wires in the mandibular vestibule. Also, there is a risk of submental scar formation and damage to structures on the floor of the mouth.[10]

The procedure involves placing Ivy loops with 24-gauge wire between 2 stable teeth, followed by a smaller-gauge wire to provide MMF between the Ivy loops. Arch bars with 24- and 26-gauge wires are also frequently used. The arch bar provides additional stability through a tension-banding mechanism, creating a second line of resistance. While placing arch bars, at least all the teeth in the affected quadrant of the mandible should be included. Encompassing the whole dental arch is not necessary. Arch bars are easy to place, have low cost, restore normal occlusion, and reduce the distraction of bone at the healing site. However, they require a second procedure for their removal and provide only semirigid fixation. In the case of an edentulous mandible, dentures can be wired to the jaw using circummandibular wires. But it has some disadvantages, including postoperative discomfort due to wires in the mandibular vestibule. Also, there is a risk of submental scar formation and damage to structures on the floor of the mouth.[10] Alternatively, MMF screws are an option to fix the dentures. MMF screws are self-tapping screws placed in the sound bone in the vestibular regions anteriorly and posteriorly. They provide a bone anchor where elastics or wires can be placed for MMF when establishing the patient’s occlusion.[11][12] Arch bars can be placed in the denture, allowing intermaxillary fixation. Gunning splints are another option in such cases.[13]

Alternatively, MMF screws are an option to fix the dentures. MMF screws are self-tapping screws placed in the sound bone in the vestibular regions anteriorly and posteriorly. They provide a bone anchor where elastics or wires can be placed for MMF when establishing the patient’s occlusion.[11][12] Arch bars can be placed in the denture, allowing intermaxillary fixation. Gunning splints are another option in such cases.[13] On the other hand, in surgical management, ie, open reduction and internal rigid fixation (IRF), the surgeon can easily visualize the fracture site and control the reduction. There is the prompt recovery of the occlusion, maintenance of periodontal tissue, reconstitution of anatomic osseous morphology to its pre-surgery form, and return to early function (due to good nutrition and verbal communication).[14] However, it carries a risk of increased morbidity. Before undergoing any surgical treatment, a tooth in the line of fracture may need to be extracted. Extraction is indicated when it is impossible or difficult to reduce the fracture due to the presence of the tooth or when the tooth has fractured roots, compromised periodontium resulting in mobility, or has an extensive periapical infection. However, the tooth may aid in guiding fracture reduction before extraction. After applying the plate across the fracture, the reduction is confirmed, and the occlusion is checked. The plates and screws are then removed, the tooth extracted, and the plate reapplied by replacing the screws in the initial holes. Surgical management can take place using an intraoral or extraoral approach, the choice of which depends mainly on the site and type of body fracture. Simple fractures of the anterior segment with no or only slight dislocation should preferably be treated with an intraoral approach.[15] This approach provides excellent access to the fracture site and allows observation of the fracture and the occlusion, reducing the fracture and enabling the application of rigid fixation. The incision is placed in the vestibular region approximately 5 to 7 mm below the mucogingival junction to facilitate closure. This location also helps prevent wound dehiscence. During an intraoral approach, care must be taken to avoid injuring the mental nerve.

Surgical management can take place using an intraoral or extraoral approach, the choice of which depends mainly on the site and type of body fracture. Simple fractures of the anterior segment with no or only slight dislocation should preferably be treated with an intraoral approach.[15] This approach provides excellent access to the fracture site and allows observation of the fracture and the occlusion, reducing the fracture and enabling the application of rigid fixation. The incision is placed in the vestibular region approximately 5 to 7 mm below the mucogingival junction to facilitate closure. This location also helps prevent wound dehiscence. During an intraoral approach, care must be taken to avoid injuring the mental nerve. On the other hand, the clinician can treat comminuted fractures in the posterior segment with a high degree of dislocation via an extraoral approach, as placing longer, stronger plates is difficult with the intraoral approach. An extraoral surgical approach is also a possibility with fractures that lie between the mandibular body's inferior and lingual aspects. Care is necessary to avoid injuring the marginal mandibular nerve.[16][17] Indications for open reduction include: Displaced unfavorable body fractures Fracture of an edentulous mandible involving a severe displacement of fracture fragments to reestablish mandible continuity. Postoperatively, patients should receive an analgesic. With open reduction, antibiotic therapy that covers gram-positive organisms is indicated. Wire cutters must remain at the bedside in case of vomiting. Reevaluation of the nutritional needs should also follow. In most adult mandibular fracture cases, intermaxillary fixation (IMF) is maintained for 4 to 6 weeks. In patients with a minimally displaced fracture in the tooth-bearing area, 2 weeks may be sufficient. After removing the wires, a radiograph is taken to confirm fracture union.

Before treating a mandibular body fracture, a thorough evaluation and monitoring of the patients' general physical conditions are necessary. The force that has caused mandibular body fractures may also injure other organ systems. There may occur concurrent posttraumatic thrombotic occlusion of the internal carotid artery or basilar skull fracture, bilateral cervical subcutaneous emphysema, pneumothorax, pneumomediastinum, and spleen lacerations after trauma. Therefore, patients should not be treated by surgical reduction of mandibular body fractures unless these issues are addressed.

Both closed and open reductions of mandibular body fractures lead to favorable bony union rates. The treatment of dental injuries should be done concurrently with the fracture, as the fractured teeth may become infected and jeopardize bone union. Hence, they require removal. As mandibular canines help determine occlusion, the clinician should preserve them if possible. The management and prognosis of edentulous body fractures are often challenging due to advanced age and multiple comorbidities.

The most common complication is infection (resulting in malunion or non-union) or osteomyelitis. Contributing factors include: Oral sepsis Teeth in the fracture line Alcohol abuse and chronic disease The prolonged time prior to treatment Poor patient compliance, Displacement of fracture fragments Fracture of the plate [18] Other complications include the delayed union of the fractured mandible. If the fracture of the body of the mandible is bilateral, along with the parasymphyseal or condylar fractures, the airway may be impaired. This impairment is due to the muscular action that pulls the distal mandibular segment backward, resulting in obstruction of the oropharynx by the tongue. There may also be nerve damage, such as neuropraxia, in which function typically returns within 4 to 6 weeks, or neurotmesis, in which function may take around 18 months to return.

A jaw fracture can affect a patient’s nutrient intake, leading to weight loss and malnutrition. Lack of proper nutrition may lead to general weakness and interfere with the healing process. Therefore, the patient must be instructed regarding the diet. During the first 3 weeks after surgery, the patient must understand they must be on a full liquid diet, including high-protein drinks, blended food, juices, and soup, and consume only a soft diet. They must receive education on the importance of eating frequently in small amounts to maintain sufficient calorie intake. They should be advised not to smoke. As malnutrition may lead to an increased incidence of infection and delayed wound healing, it is important that the patient records their weekly weight to help guide nutritional support. For illiterate patients, the use of pamphlets and simple illustrated booklets may educate them about living safely and maintaining a normal body weight.

Mandibular body fractures may be associated with significant other traumatic injuries. In some cases, the airway may also undergo compromise. Hence, to enhance outcomes, care for such patients should be delivered through an interprofessional team approach that includes clinicians and specialty-trained emergency and trauma nurses. For example, if occlusion is affected, a prosthodontist must be consulted to achieve the patient's optimal occlusion. Also, for edentulous patients in whom the fabrication of dentures or a gunning splint is necessary, a prosthodontist can help fabricate the prosthesis with an appropriate vertical dimension. The trauma nurse has involvement through the surgical or reduction procedures. Other nurses are responsible for monitoring the patient's progress and dietary compliance, answering patient questions, and keeping the clinical team informed every step of the way. With an interprofessional team approach, patients with mandibular fractures can achieve optimal outcomes and have increased odds of resuming normal life.