Three-dimensional analysis of the palatal morphology in growing patients with Apert syndrome and Crouzon syndrome

Patients with Apert syndrome or Crouzon syndrome present with severe defects in oral-maxillofacial growth and development. In this study, we conducted a quantitative three-dimensional (3D) analysis of the palatal morphology of patients with Apert syndrome and Crouzon syndrome. Four patients with Apert syndrome (average age, 11.0 ± 0.8 years) and five with Crouzon syndrome (average age, 10.1 ± 1.6 years) were investigated. The participants' maxillary dental casts were scanned and analyzed using 3D imaging. Palatal width, depth, cross-sectional area, and palatal angle (PW, PD, PCA, and PA, respectively) were measured, and standard scores were calculated based on sex- and age-matched Japanese standard values; the actual palatal surface areas (PSA) and palatal volumes (PV) were also measured. Our results show that patients with Apert syndrome and Crouzon syndrome had a very narrow PW (standard score: −3.79 and − 0.47, respectively). 3D analysis revealed that patients with Apert syndrome had a significantly shallower PD (standard score: −1.35) than those with Crouzon syndrome (standard score: 2.47), resulting in a smaller PCA (standard score: −5.13), PSA (5.49 cm²), and PV (1.11 cm³) and larger PA (standard score: −0.12) than those in patients with Crouzon syndrome. This might be due to the former having a narrower and shallower palate caused by the predominant swelling of the palatal mucosa. These findings improve our understanding of the differences in palatal morphology between Apert syndrome and Crouzon syndrome patients.