3. The Effect of the Degree of Mandibular Distraction Osteogenesis on Palatoplasty Timing in Patients with Micrognathia and Cleft Deformities

PURPOSE: Patients with congenital micrognathia often have severe obstructive sleep apnea (OSA) and concomitant cleft palate (CP) requiring mandibular distraction osteogenesis (MDO) followed by palatoplasty. This study aims to identify how MDO distance affects CP repair timing and outcomes. METHODS: A retrospective review was conducted for patients with CP and micrognathia who underwent MDO at a single institution from 2006-2022. Patients who underwent maximal MDO (MMDO) (30 mm) were compared to those with submaximal distraction (SMD). Distraction distance, palatoplasty timing, and postoperative outcomes were collected. RESULTS: Upon review, 90 patients underwent MDO, 74 had concomitant CP. Fifty-one patients (68.9%) underwent MMDO and 23 (31.1%) SMD (average distraction distance 21.0±7.51mm). In patients without genetic syndromes, MMDO was associated with a shorter time from MDO to palatoplasty than SMD (13.9±10.9 vs 14.5±4.9 mo, p=0.042). Of patients older than 12 months at palatoplasty, there was a higher CP revision rate in the SMD group (p=0.036). Logistic regression showed abnormal AHI (>5) as the only statistically significant contributor to higher revision rate in the SMD cohort. CONCLUSION: Timing of palatoplasty after MDO requires balancing normal speech development with the safety of airway narrowing in known OSA. SMD was associated with a higher CP revision rate compared to MMDO in late repairs; this effect was moderated by abnormal postoperative AHI. When counseling patients with micrognathia and CP, aggressive MDO for OSA management is an important consideration for timely CP repair and optimal outcomes.