What is the immediate management and treatment for a mandibular (lower jaw) fracture?

Immediate Management and Treatment of Mandibular Fractures

For acute mandibular fractures, obtain CT maxillofacial imaging immediately to confirm the diagnosis and identify the nearly universal second fracture (present in 67% of cases), followed by airway assessment, pain control, antibiotics if open fracture, and definitive surgical fixation with open reduction and internal fixation (ORIF) using rigid plate fixation, with or without brief maxillomandibular fixation (MMF) depending on fracture stability. 1, 2, 3

Initial Assessment and Imaging

Diagnostic Imaging

• CT maxillofacial with multiplanar reformations is the gold standard, achieving nearly 100% sensitivity for mandibular fractures with superior detection of subtle nondisplaced fractures compared to conventional radiography 1, 2, 3
• Always search for a second fracture after identifying the first—the mandible's U-shaped ring configuration results in two separate fractures in approximately 67% of cases 1, 3
• Common dual fracture patterns include:
  • Mandibular angle or subcondylar fracture with contralateral parasymphyseal fracture 1, 3
  • Flail mandible: bilateral subcondylar fractures with symphyseal fracture 1, 3

Critical Associated Injuries to Evaluate

• Screen for intracranial injury—present in approximately 39% of patients with mandibular fractures 1, 2, 3
• Evaluate for cervical spine injury—occurs in approximately 11% of patients 2, 3
• Assess for inferior alveolar nerve damage—fractures extending through the mandibular canal can damage this nerve 1
• 20-40% of patients have additional injuries beyond the mandible 1, 2, 3

Immediate Stabilization

Airway Management

• Secure airway first if compromised, particularly with bilateral body fractures or flail mandible 1

Pain Control and Antibiotics

• Initiate appropriate analgesia immediately 4
• Administer systemic antibiotics for open fractures (fractures communicating with oral cavity or through skin) 5
• Infected fractures result from moving fragments and nonvital bone, not just bacteria—controlling movement is essential 5

Definitive Treatment

Surgical Fixation: The Primary Treatment

Open reduction and internal fixation (ORIF) with rigid plate fixation is the definitive treatment for displaced mandibular fractures, providing stable fixation that allows early mobilization 4, 5

• Use 2.0-mm titanium miniplates for adequate stability in most fractures of the tooth-bearing mandible 4
• Plates can be secured transoral or percutaneously depending on fracture location 4
• Primary bone grafting should be performed if debridement of infected or nonvital bone creates a defect, achieving primary union in 95% of cases (20 of 21 infected fractures) 5

Maxillomandibular Fixation (MMF): Duration Controversy

The evidence supports either immediate mobilization OR brief (2-week) MMF following rigid internal fixation for displaced fractures between the mandibular angles:

Option 1: Immediate Mobilization (Preferred for Patient Comfort)

• No statistically significant differences in outcomes compared to 2 weeks of MMF 4
• Mean weight loss: 10 pounds with immediate release vs 8 pounds with MMF 4
• Mean trismus: 4.2 cm with immediate release vs 4.6 cm with MMF 4
• No malunion, nonunion, or infections in the immediate mobilization group 4

Option 2: Short-Period MMF (2 Weeks)

• For fractures requiring additional stability, 2 weeks of MMF followed by arch bar splint wired to lower jaw is effective 6
• Significantly greater mouth opening at 1 week post-treatment compared to conventional long-term MMF (P = 0.001) 6
• No significant difference in mouth opening compared to controls by 3-6 months 6
• Reduces adverse effects of long-term MMF while maintaining fracture stability 6

MMF Techniques (When Used)

Maxillomandibular fixation screws (MMFS) are preferred over traditional arch bars when MMF is indicated:

• Reduces operating time 7
• Minimizes tissue damage to teeth and periodontal structures 7
• Decreases patient discomfort during fixation period 7
• Eliminates surgeon exposure risk to blood-transmitted diseases from wire punctures 7
• Facilitates easier oral hygiene maintenance 7

Alternative: If patient has existing orthodontic brackets, these can be utilized for MMF without removal 8

Critical Pitfalls to Avoid

• Never miss the second fracture—systematically examine the entire mandible on CT after identifying the first fracture 1, 3
• Do not rely on conventional radiography alone—sensitivity is only 86-92% and misses nondisplaced fractures, anterior fractures (overlap with cervical spine), and condylar/subcondylar fractures with anterior displacement 2, 3
• Do not use prolonged MMF unnecessarily—immediate mobilization after rigid fixation achieves equivalent outcomes with better patient tolerance 4
• Always address infected fractures with rigid fixation and debridement—controlling fragment movement and removing nonvital bone is as important as antibiotics 5
• Screen for associated injuries—nearly 40% have intracranial injuries and 11% have cervical spine injuries 1, 2, 3