Treatment Burden and Premature Consolidation in Rigid External Distraction for Maxillary Advancement: A Single-Institution Cohort Review

Background: Patients with cleft lip and/or palate often develop maxillary hypoplasia and Class III malocclusion, and a subset requires surgical maxillary advancement via distraction when orthodontic compensation is insufficient and the maxillary retrusion exceeds the limit of a standard Le Fort I advancement. Rigid External Distraction (RED) affords greater control of the distraction vector through postoperative adjustments but can introduce device and management burden. This study assesses treatment burden and rates of premature consolidation in patients undergoing Le Fort I maxillary distraction. Methods: This institutional review board approved retrospective cohort study evaluated consecutive eligible RED cases performed between November 2015 and May 2024 for cleft-related maxillary hypoplasia. Data were collected retrospectively from the electronic medical record. Complications were classified into premature consolidation, hardware complications, vector/occlusal disturbances, trauma, and device migration. Treatment burden was quantified by clinic and operative interventions occurring after the index procedure and before consolidation. Results: Twenty-five patients ages 9 to 20 years underwent Le Fort I maxillary advancement with RED. Latency averaged 6 days. Distraction was initiated at 1.0 mm/day in all patients and 7 patients required rate escalation above 1.0 mm/day during activation. Four of these patients (16%) proceeded to premature consolidation, with 3 necessitating reoperation for re-osteotomy and device repositioning to resume advancement. Within the rate-escalation subgroup, patients who developed premature consolidation had a significantly higher baseline negative overjet than those salvaged without premature consolidation. Overall treatment burden was substantial, with 16 patients (64%) requiring at least 1 clinic intervention and 9 (36%) requiring 1 operative intervention. Stable advancement was documented in all patients, and no patients developed nonunion. Conclusion: In this RED patient cohort, treatment burden was substantial and reflected frequent outpatient management of hardware issues and vector/occlusal adjustments. Premature consolidation was uncommon and early rate escalation when resistance is noted can salvage the distraction.