https://www.selleckchem.com/products/VX-770.html Additionally, cleft of the soft palate, anterior open bite, severe crowding in the maxillary dental arch, and congenitally missing teeth occurred more frequently among AS patients. Multiple fusions between cervical vertebrae C2, C3, C5, and C6 were observed in the AS patients. LIMITATIONS Small sample size. CONCLUSIONS/IMPLICATIONS Our study shows that AS patients have more severe craniofacial and maxillofacial deformities than CS patients. © The Author(s) 2020. Published by Oxford University Press on behalf of the European Orthodontic Society. All rights reserved. For permissions, please email journals.permissions@oup.com.BACKGROUND The aim of this retrospective cohort study was to assess long-term occlusal changes at debond and a median of 8 years afterwards (in retention) with the American Board of Orthodontics (ABO) objective grading system and identify risk factors. MATERIALS AND METHOD Fifty patients (median age 14.3 years at debond; 60% female) treated with fixed appliances (25 with and 25 without premolar extractions) were included. The occlusal outcome was assessed with the ABO tool and analyzed statistically at 5%. RESULTS Extraction treatment was associated with better occlusal outcome than non-extraction treatment (34.2 versus 40.9 points; P = 0.009). In retention, ABO scores improved by 7.4 points, while patients with worse debond finishing improved more afterwards (P = 0.001). Alignment/rotations deteriorated in 58% of the cases and occlusal relationships in 38% of the cases. Marginal ridges improved more for extraction than non-extraction patients (28% versus 0%; P = 0.001). Occlusal relationships improved more for cases that 'passed' the ABO requirements at debond than failed cases (64% versus 28%; P = 0.02). Furthermore, patients with worse debond ABO scores were more likely to deteriorate at alignment/rotations in retention. Finally, the proportion of cases passing the ABO requirements improved consi