Cephalometric norms of Chinese: McNamara analysis

Abstract

AIM: To establish cephalometric norms in Chinese using McNamara’s (1984) analysis, and to compare them with those of Caucasians. MATERIALS AND METHOD: Lateral cephalometric radiographs taken in natural head posture of a random sample of 200 male and 205 female 12-year-old southern Chinese together with 43 male and 43 female 12-year-old British Caucasian children in Hong Kong. The radiographs were digitised twice with the CASSOS program. RESULTS: In males, the effective midface height, facial axis angle and pogonion to nasion perpendicular were significantly larger in Caucasians than in Chinese, while SNA, maxillomandibular difference, mandibular plane angle, upper incisor to point A and lower incisor to A-Po line were significantly larger in Chinese males than in Caucasian males. In females, the effective midface height and facial axis angle were significantly larger in Caucasian than in Chinese, while the maxillomandibular difference, lower anterior face height, mandibular plane angle, upper incisor to point A and lower incisor to A-Po line were significantly larger in Chinese females than in Caucasian females. CONCLUSION: There are significant differences between Caucasian and Chinese cephalometric norms using McNamara’s analysis.