The craniofacial characteristics of osteogenesis imperfecta patients

The aim of this study was to identify the craniofacial characteristics of 16 osteogenesis imperfecta (OI) patients, 10 males and 6 females, aged 7-15 years. The control group comprised 863 Chinese children from 6 to 18 years of age. Eleven cephalometric reference points and 25 variables were measured on the lateral cephalometric radiographs. Cochrane's method of unequal variance f-test was used to differentiate the differences between two groups. A Class III occlusal relationship was found in 62.5 per cent of the OI patients. The maxilla was more retrusive than the mandible in relation to the cranial base. Face heights, the effective maxilla and mandibular lengths, and anterior and posterior cranial base lengths were significantly shorter than the control subjects. The facial divergence, the cranial base (N-S-Ar, P < 0.001), and the gonial (Ar-Go-Gn, P < 0.001) angles were significantly enlarged, while the articular angle (S-Ar-Go, P < 0.001) was significantly reduced. The findings showed that the OI patient had a more prominent Class III occlusal relationship, prognathic mandible, larger facial divergence, shorter face heights, defective sagittal growth of the maxilla and mandible, a flattened cranial base angle, impaired cranial base growth, and more forward counterclockwise rotation in mandibular growth compared with the controls.