Figure 4.

Three individuals affected by OI type III. Note that the triangular face appearance is attributable to the combination of cranial flaring and hypoplastic lower face. All three patients demonstrate the lack of vertical development of the maxilla and insufficient descent of the upper molars, resulting in bilateral open bite. Patients A and B have severe nasal septum deviation. Patient A has platybasia; patients B and C have both platybasia and basilar invagination (C2ap‐McRae stands for the distance of the apex of the second cervical vertebra above the plane of foramen magnum known as McRae reference line). Patients A and C have sufficient patency of pharyngeal airways.