Three-Dimensional Assessment of Craniofacial Features in Patients With Down Syndrome During the Mixed Dentition Period: A Case-Control Study

Objectives: Down syndrome (DS) is a common congenital chromosomal disorder related to trisomy 21. Lateral cephalometric radiography studies have shown that patients with DS have characteristic craniofacial morphology; however, no 3-dimensional analysis studies have been performed to investigate the craniofacial features, including volumetric aspects, of patients with DS. The present study was performed to evaluate the craniofacial features, including volumetric aspects, of patients with DS and to compare these findings with control participants using cone beam computed tomography (CBCT). Materials and Methods: The study sample consisted of 12 patients with DS and 12 control participants. All participants were examined by means of CBCT; the resulting images were used for evaluation of maxillary and mandibular volume, cranial base, and craniofacial measurements. Differences between patients with DS and control participants were statistically analyzed using Student t test. Results: Compared to control participants, patients with DS exhibited statistically significant reductions in maxillary and mandibular volumes. Both sagittal and axial cranial base linear measurements were shorter in patients with DS than in control participants. In contrast, the cranial base angle was enhanced in patients with DS, compared with control participants. Moreover, condylion (Co)-gnathion, anterior nasal spine-menton, and Co-subspinale (point A) measurements were shorter in patients with DS than in control participants; the sella-nasion-mandibular plane angle was significantly reduced in patients with DS, compared with control participants. Conclusion: Our results suggest that patients with DS have distinct skeletal volume and craniofacial morphology features, relative to individuals without DS.