IMPORTANCE: Patients with severe micrognathia are predisposed to airway obstruction. Mandibular distraction osteogenesis (MDO) is an alternative to tracheotomy that lengthens the mandible in order to improve the retrolingual airway. This study presents outcomes from one of the largest cohorts reported. OBJECTIVE: To assess the rate and predictors of surgical success and complications among (1) patients who underwent MDO prior to other airway procedures (MDO first), and (2) patients who required an initial tracheotomy and were subsequently treated with MDO (tracheotomy first). DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort study at a tertiary care pediatric medical center of patients diagnosed as having micrognathia resulting in symptomatic airway obstruction (Pierre Robin sequence) and who underwent MDO from September 1995 to December 2009. INTERVENTIONS: Electronic medical records were reviewed. Multivariable regression analysis was used to assess for predictors of outcome. MAIN OUTCOMES AND MEASURES: Rates of surgical success (defined as either tracheotomy avoidance or decannulation) and complications. Potential predictors included demographics, syndrome presence, follow-up time, and surgical history. RESULTS: A total of 123 patients (61 in MDO-first subgroup, 62 in tracheotomy-first subgroup) underwent MDO during the study period. Median age at time of distraction was 21 months (range, 7 days-24 years). Surgical success and complication rates were 83.6% and 14.8% in the MDO-first subgroup and 67.7% and 38.7% in the tracheotomy-first subgroup. Tracheotomy-first patients were more likely to have a syndromic diagnosis (66.0% vs 43.0%; P = .009) and were older at the time of MDO (median age, 30 months vs 5.1 months; P < .001). Poorer odds of success were associated with the need for 2 or more other airway procedures (odds ratio [OR], 0.14 [95% CI, 0.02-0.82]) in the MDO-first subgroup and craniofacial microsomia or Goldenhar syndrome (OR, 0.07 [95% CI, 0.009-0.52]) in the tracheotomy-first subgroup. CONCLUSIONS AND RELEVANCE: Mandibular distraction osteogenesis has a high rate of success in avoiding tracheotomy. Patients who required a tracheotomy before MDO had a lower success rate in achieving decannulation and a higher rate of complications. However, these patients also had a higher rate of syndromic diagnoses and associated comorbidities. Patients with Goldenhar syndrome have a decreased likelihood of surgical success.