The management of pediatric facial fractures requires several considerations by the treating surgeon. Pediatric facial fractures occur less commonly than in adults. Among fracture patterns in children, studies have repeatedly demonstrated that mandible fractures are the most common facial fracture particularly the condyle. Most fractures in children are amenable to nonsurgical or closed treatment; however, certain indications exist for open treatment. The literature describing epidemiology, treatment trends, and long-term outcomes are limited in comparison with adult populations. The purpose of the article is to review the etiology, workup, and management of mandible fractures in children
Key points
- •
Pediatric facial fractures are uncommon; the mandible is the most commonly fractured facial bone. Many pediatric mandible fractures can be managed nonsurgically or with closed techniques.
- •
Available data suggest similar outcomes between closed versus open treatment.
- •
Open treatment may be warranted in cases of severe displacement, multiple fractures, or inability to tolerate intermaxillary fixation.
Background
Craniomaxillofacial surgeons managing pediatric mandible fractures should have a general understanding of growth and development of the pediatric facial skeleton, which also helps contextualize the statistics surrounding pediatric mandible fractures. Growth cessation of the mandible occurs later than all other facial bones (age 14–16 years in females; 18–20 years in males). , The condyle is believed to be a primary growth center of the mandible, and the damage during periods of active growth may lead to significant growth disturbance. , Fortunately, many factors reduce the frequency of mandibular fractures in children as compared with adults. From infancy through the mixed dentition, the cranium is proportionally larger than the face providing relative protection against facial injuries. Bone in children has a lower elastic modulus than adults, decreasing the frequency of fractures. Tooth buds during the primary and mixed dentition comprise most of the volume of the developing mandible and are thought to be protective against fractures. Common fracture patterns in pediatric patients include incomplete or “green stick” injuries where cortical violation may be unilateral and incomplete. These biomechanical considerations may explain why facial fractures in children are often associated with other injuries, morbidity, and mortality.
Epidemiology
Several institutional-based studies describe epidemiology and demographics surrounding mandible fractures. The most common mechanisms of injury are motor vehicle collisions followed closely by assault/abuse, mechanical falls, and sports-related injuries. As in adults, there is a strong male predilection and the average age is 9 to 12 years. , Dental crown fracture and tooth avulsion commonly occur with pediatric mandible fractures. The most common pediatric mandibular fracture location overall in children is the mandibular condyle/subcondylar region followed by the symphysis, but the predominance varies by age and mandibular development. Children less than 8 years more commonly have condylar head fractures, but after this, the condylar neck enlarges and condylar neck fractures predominate. Mandibular body and angle fractures become more common as the mandible completes development.
Owusu and colleagues conducted a review of the Healthcare Cost and Utilization Project–Nationwide Emergency Department Sample, a comprehensive database available for emergency department encounters in the United States. Their study corroborated previous institutional and regional studies. They also reported a male predilection (4:1) and consistent age-related distribution and location of fracture (condyle fractures as the most common site of injury overall [14%]). Condylar fractures were most common less than 12 years old secondary to falls, whereas greater than 12, fractures of the angle of the mandible predominated. In addition, they found a relationship between anatomic site and gender; males were more likely to have angle fractures (15%), whereas females had more condylar fractures (20%).
Clinical assessment
Initial evaluation and management follows advanced traumatic life support protocols for identification and management of life-threatening injuries. Mandible fractures in children are commonly associated with intracranial and/or cervical spine injuries. In-line stabilization of the cervical spine should be maintained during evaluation and operative management if injuries are suspected or cannot be ruled out. , In children, standard history and physical examination can be limited by an inability to describe symptoms such as pain, vision changes, or malocclusion. Assessment should be done with the input of caregivers where appropriate. A thorough physical examination is warranted assessing for predictors of facial fractures. Soft tissue injuries including swelling, laceration, or ecchymoses may provide a gauge of injury severity. Concomitant dentoalveolar injuries occur in nearly 25% of pediatric mandible fracture with tooth avulsion representing the most common associated injury. Any teeth unaccounted for require imaging to rule out aspiration. The clinician should determine the child’s dentition pattern (primary, mixed, or adult), inspect for soft tissue injuries extra- and intraorally that can indicate adjacent fractures. Examination findings vary by fracture location but can include malocclusion, step-offs in the inferior border or dentition, mobility of fracture segments, trismus, deviation to the ipsilateral side on opening, and paresthesia of the lower lip and/or chin.
Imaging
Imaging studies to assess fracture patterns may include two-dimensional (2D) plain film or 3D studies. Plain x-ray imaging (eg, panoramic radiograph or facial series) has several limitations in the pediatric population that may lead to a misdiagnosis: (1) presence of tooth buds, overlap of anatomic structures, and the developing ramus–condylar units may obscure visualization of fracture patterns and (2) limited patient compliance may introduce motion artifact preventing accurate diagnosis. Computed tomography (CT) imaging is widely accepted as the clinical gold standard for patients sustaining facial trauma for its 3D visualization of fracture patterns. In children, CT imaging more reliably detects fractures with greater sensitivity and specificity compared with panoramic imaging, especially for condylar fractures. Given concerns about ionizing radiation in the growing patient, clinicians should adhere to ALARA (as low as reasonably achievable) principles. , MRI has been applied recently for children sustaining trauma. MRI may provide suitable sensitivity and specificity for diagnosis of mandible fractures while eliminating radiation, but more studies are needed. Limitations include a lack of 3D skeletal images and longer acquisition time which could result in motion artifact and/or necessitate sedation in young patients.
Management
The goal of treatment for mandibular fractures is to restore mandibular form and function and minimize growth disturbance. Factors to consider include patient age, fracture pattern, degree of displacement, risk for growth disturbance, and ability to comply with instructions. Owing to these factors, pediatric facial fractures have increasingly been managed at tertiary medical centers.
Nonsurgical or closed treatment of pediatric mandible fractures has long been an accepted treatment pattern where there is minimal change in occlusion or fractures are non-displaced. , Factors in favor of this treatment option include rapid healing, potential for occlusal correction with eruption of permanent teeth, growth compensation, and avoidance of the operative risks of open treatment. In addition, sustaining a mandible fracture has not been correlated with need for future orthodontic treatment. For non-displaced fractures, without malocclusion or limitation in opening can be managed by a limited diet (ie, blenderized), analgesics, and close observation. Advancement to soft foods and early return of function is emphasized to prevent limited mouth opening or temporomandibular joint (TMJ) ankylosis. Gentle jaw-opening exercises are added shortly after diagnosis particularly with intracapsular condylar fractures. Children in the primary or mixed dentition with a minor malocclusion have the potential for dental compensation may also be managed with nonsurgical treatment.
Children with malocclusion or displacement of fractures usual require surgical intervention. Closed treatment (ie, maxillomandibular fixation [MMF]) can be instituted in mild/moderate displacement. Severely displaced fractures or those that cannot be reduced using closed techniques require open treatment which can include reduction and internal fixation. Some cases may require a combination of open reduction internal fixation with closed treatment such as a displaced body fracture and condylar fracture ( Fig. 1 ).
Closed Versus Open Treatment Techniques
Closed treatment serves to immobilize or guide the mandible to the patients’ premorbid occlusal relationship to help maintain bony anatomic reduction. Advantages include the decreased risk of iatrogenic injury associated with periosteal stripping for exposure, damage to tooth buds or need for subsequent hardware removal. In the pediatric population, the state of the dentition (primary, adult, mixed) must be assessed as this will influence the choice of intermaxillary fixation. The traditional circumdental wiring using Eric arch bars may not be feasible in the primary or early mixed dentition where bulbous crowns with lower height of contour limit retention of wires and adaptability of an arch bar. Risdon cables (braided 26-gauge wires secured with circumdental wires) better adapt to primary teeth and allow wired MMF ( Fig. 2 ). Occasionally preexisting orthodontic appliances can be used for elastic or wire maxillomandibular guidance or fixation. If circumdental wiring is not possible (eg, multiple missing teeth), circummandibular wiring can provide stability and reliable outcomes. Occlusal and lingual splints can be used for additional stability when the dentition is limited. A lingual splint (either made preoperatively or intraoperatively using thermoplastic material) can help establish the width of the mandible with a symphysis fracture and can be used with closed and as an adjunct to open treatment ( Fig. 3 ).
Closed treatment duration should be shorter in children as compared with adults. For children in the primary or mixed dentition, rarely is more than 2 weeks of MMF necessary. Gentle stretching exercises should be prescribed after MMF to regain motion particularly with fractures of the condyle with observation of the amount of opening over several months.
The use of progressively remodeled splints combined with fixed orthodontic appliances can lead to satisfactory TMJ function in patients with mixed dentition. There are however age-determinant outcomes associated with closed treatment. The closed treatment of condylar fractures in older children (>12 years of age) has higher rates of posttreatment malocclusion, TMJ dysfunction, and mandibular deviation. In addition, they have more persistent radiographic changes of ramus–condylar morphology.
Open treatment may be indicated when there is significant fracture displacement, bilateral injuries, or adolescents with condylar neck injuries. When open treatment is used, plate and screw fixation should be placed along the inferior border of the mandible to avoid damage to unerupted teeth and dental follicles. When tooth follicles occupy a large vertical proportion of the body space and fixation is needed, monocortical fixation with short screws should be used. Theoretically, fixation should not cross the midsagittal plane as it may restrict growth. The position of the inferior alveolar nerve (IAN) also changes during development and should be accounted for when placing fixation. Initially, the IAN is positioned inferior-lingually and progressing superiorly toward the middle of the mandible.
Open treatment of pediatric mandible fractures can be achieved with a variety of materials for rigid osteosynthesis. Most surgeons prefer the use of titanium as for familiarity given use in adults, biocompatibility, accessibility, and ease of adaptation to the skeleton. Titanium osteosynthesis is biomechanically superior to resorbable systems and less technique sensitive. Concerns of growth restriction or translocation of hardware medially and posteriorly with growth has led to planned removal or use of resorbable plating systems.
Resorbable osteosynthesis can be used for some mandible fractures. They offer the theoretical advantage of less growth disturbance and can avoid a second operation for removal. Resorbable plating systems are commonly made from polymers of polyglycolic and poly-L-lactic acid that require several months to dissolve. They may require pre-tapping after drilling screw holes. Fixation with resorbable plates should be applied in a load-sharing manner due to less fixation strength. Some surgeons therefore combine a short period of MMF with the use of resorbable plating techniques. Unlike titanium plates, resorbable plates have poor memory and therefore do not provide reliable contouring or overreduction. Previous studies have demonstrated no significant difference in rates of infection between resorbable and titanium plates. ,
Symphysis and body fractures
As tooth buds are protective, fractures due to direct trauma to the symphysis and body occur more commonly in older children. Most fractures are non-displaced and favorable. Children sustaining an isolated and nonmobile fracture may be managed with observation and limited diet. Close monitoring is recommended to allow intervention with changes in the fracture or occlusion.
With mobility or displacement, closed treatment or open reduction internal fixation (ORIF) should be used. A single plate can be placed at the inferior border along with stabilization of the dentition using arch bars or Risdon cables (see Fig. 3 ). As above, width can be restored using a lingual splint ( Fig. 4 ); “Tension bands” should not be used due to developing teeth. The dental fixation can be removed 4 to 6 weeks after fixation and the plate if indicated removed after 4 to 6 months.
