Computed Tomography Analysis of Craniofacial Features in Japanese Patients With Cleidocranial Dysplasia

Cleidocranial dysplasia is a congenital malformation syndrome characterized by skeletal and dental abnormalities as well as distinctive craniofacial features. Most previous reports have relied on two-dimensional radiographs, and no comprehensive three-dimensional investigations have been conducted. This study aimed to provide a detailed overview of craniofacial features in patients with cleidocranial dysplasia using computed tomography. Craniofacial characteristics of 11 Japanese patients were assessed using three-dimensional computed tomography reconstructions. Qualitative evaluations were performed across three regions: cranial, nasomaxillary complex, and mandibular. In the cranial region, all patients presented Wormian bones and hypoplastic mastoid processes. In the nasomaxillary complex, hypoplastic nasal bones, atypical piriform aperture contours, and discontinuous or downward-bent zygomatic arches were frequently observed. In the mandibular region, atypical sigmoid notch morphology, nearly parallel-sided ascending rami, and abnormally rounded mandibular angles were identified. Novel findings included aplastic/hypoplastic styloid processes, thin-appearing orbital walls, downward displacement of the temporal process of the maxillary bone, and atypical coronoid process morphology. Bilateral expression of all craniofacial traits was also newly confirmed. To our knowledge, this is the first comprehensive three-dimensional study of craniofacial morphology in cleidocranial dysplasia. These observations provide new insights into the pathophysiology and developmental mechanisms underlying craniofacial anomalies in affected patients.