Extended Antibiotic Prophylaxis Not Associated With Improved Outcomes Following Open Reduction of Mandible Fractures

BACKGROUND: Although current guidelines discourage extended antibiotic prophylaxis, it remains commonly used in the clinical practice of mandible fractures. The current study evaluated associations between extended preoperative or postoperative antibiotic prophylaxis, and 90-day adverse events after open reduction and internal fixation (ORIF) of closed mandible fractures. METHODS: Patients undergoing ORIF for closed mandible fractures were identified from a large, national, administrative database and stratified by antibiotic exposure: extended preoperative prophylaxis (defined as antibiotic exposure the same day as fracture to one day before ORIF), extended postoperative prophylaxis (within 1 wk after ORIF), or no documented extended antibiotics beyond standard perioperative care. Exclusion criteria included long bone fractures, age under 18, history of dental caries or implants, fewer than 90 days of follow-up, and early postoperative infectious diagnoses that would indicate antibiotics were given for treatment rather than prophylaxis. Primary outcomes included 90-day surgical site infections, osteomyelitis, face abscess, wound debridement, nonunion, malocclusion, wound dehiscence, hardware removal, and overall complications. Multivariable logistic regression controlled for patient demographics and comorbidities. RESULTS: Of 16,110 patients identified, extended preoperative antibiotics were used for 9.4%, extended postoperative antibiotics were used for 26.2% of patients, and no extended prophylaxis was used for 64.4%. Although debridement rates were slightly lower in the postoperative antibiotic group versus no prophylaxis (0.5% versus 1.1%; P=0.003), neither preoperative nor postoperative antibiotics were associated with any other reduced postoperative complications on univariable or multivariable analyses. CONCLUSIONS: Extended outpatient antibiotic prophylaxis was not associated with improved outcomes after ORIF of closed mandible fractures. These findings call this practice into question.