Contributing Factors for Angle's Class III Phenotype in Crouzon Syndrome.

Crouzon syndrome (CS) is a rare genetic condition characterised by craniofacial malformations due to mutations in the FGFR2 gene. This study aimed to evaluate the contributing factors for Angle's Class III malocclusion in patients with CS through cephalometric analysis. Six patients with confirmed CS diagnosis were included in the study. Cephalometric measurements were performed using CT scans and compared to established norms. Pathogenic variants in the FGFR2 gene were identified in all patients. Phenotypic and cephalometric characteristics were assessed in each patient. Results showed consistent craniofacial abnormalities, including midface retrusion, mandibular prognathism, and malocclusion. Cephalometric analysis revealed specific patterns indicating growth deficiency at the posterior base of the skull, maxillary retroposition, and an anterior accommodation of the mandibular condyles in the glenoid fossa. These findings provide valuable insights into the underlying factors contributing to Angle's Class III malocclusion in patients with Crouzon syndrome.