2.1 | Subjects and ethical approval
The study involved four non-consanguineous patients with NSTA who were
referred to the Department of Prosthodontics, School and Hospital of
Stomatology of Hebei Medical University, and 100 non-consanguineous
controls. All participants were examined by prosthodontics specialists
to determine the status of dentition. An oral examination and a dental
treatment history were performed, and panoramic radiographs were taken
to confirm the congenital absence of teeth (Figure 1). The study was
conducted under the approval of the Ethics Committee of the School and
Hospital of Stomatology, Hebei Medical University (NO: [2016] 004).
All participants or their guardians signed written informed consent.