Soft-tissue profile changes following early le fort iii distraction in growing children with syndromic craniosynostosis

BACKGROUND: The purpose of this study was to characterize soft-tissue profile changes following Le Fort III (midface) distraction in growing patients with syndromic craniosynostosis. METHODS: The cohort consisted of 20 syndromic patients who underwent Le Fort III osteotomy with midface advancement using a rigid external distraction device. The mean age at surgery was 5.7 years (range, 3 to 12.5 years). Lateral cephalograms were obtained preoperatively (time 1), after distraction device removal (time 2), and 1 year after distraction (time 3). Ten skeletal hard-tissue and 11 soft-tissue profile landmarks were identified and digitized at time points 1, 2, and 3. The x and y displacement of each landmark was studied to determine the ratios for soft-to hard-tissue change. RESULTS: The horizontal ratio of soft-to hard-tissue change for nasal dorsum to orbitale was 0.73:1 and the soft-tissue tip of nose to the anterior nasal spine was 0.86:1. The horizontal ratio of soft-tissue A point to hard-tissue A point was 0.88:1. The horizontal ratio of the upper lip position to the labial surface of maxillary incisor was 0.88:1. The ratio for nasal tip elevation to the anterior nasal spine advancement was 0.27:1. CONCLUSIONS: The result of this study supported the hypothesis that there exists a linear relationship between soft-and hard-tissue changes in the horizontal direction for the midface landmarks following Le Fort III distraction. However, there was a nonlinear relationship between soft-and hard-tissue changes in the vertical direction.