A multicentre study on hereditary craniofacial anomalies in orthodontic patients in Japan: clinical characteristics and insurance eligibility

Purpose Health-insurance coverage for orthodontic treatment in patients with congenital disorders has expanded in Japan; however, many conditions remain unrecognized. Therefore, this study aimed to clarify the clinical characteristics and health-insurance eligibility for hereditary craniofacial anomalies in Japan.Materials and methods We included patients with congenital craniofacial anomalies (excluding nonsyndromic cleft lip and/or palate) who visited the Departments of Orthodontics at nine university hospitals up to December 2024. Disease names and insurance eligibility data were collected using an electronic data-capture system.Results Of the total 1,224 patients (640 males and 584 females) registered, 1,107 (90.4%; 95% confidence interval [CI], 88.6–92.0) were diagnosed with one of the 65 health insurance-covered disorders. The most frequent diagnoses were congenital absence of ≥6 teeth (343, 28.0%), followed by Down syndrome (102, 8.3%), craniofacial microsomia (67, 5.5%), craniosynostosis (53, 4.3%), cleidocranial dysplasia (50, 4.1%), Turner syndrome (46, 3.8%), osteogenesis imperfecta (36, 2.9%), Pierre Robin sequence (34, 2.8%) and achondroplasia (34, 2.8%). Among the 117 patients (9.6%; 95% CI, 8.0–11.4) with other disorders, 58 (4.7%; of total cohort) were eligible for health-insurance coverage owing to symptoms overlapping those of the 65 designated disorders or diagnosis of cleft lip and/or palate or jaw deformities. The remaining 59 patients (4.8%; 95% CI, 3.7–6.2) were ineligible for health insurance.Conclusion Although most hereditary craniofacial anomalies are currently covered by health insurance, many rare conditions are excluded. Continued data collection and expansion of participating institutions are essential for establishing a more comprehensive support system.