Cephalometric standards for the southern Chinese

This study presents selected dento-skeletal and soft tissue profile population standards (norms) for southern Chinese children in Hong Kong. The random samples comprised 120 male and 120 female 12-year old subjects. Tabular data and computer graphics are presented for the males and compared to the females. All radiographs were recorded in natural head posture. Conventional analysis has shown the Chinese male to be sagittal Class I (ANB = 3.6°) with bimaxillary dental and alveolar protrusion. The males were 1–2 per cent larger in overall linear dimensions but very few significant intersex differences in angular measurements were found. The lips were more protrusive in the males (p ≤ 0.001). For the dental variables the overbite was significantly greater in the males, with p ≤ 0.01, but the overjet showed no significant difference. Because the great majority of both the Hong Kong Chinese population and the overseas Chinese originated from the southern province of China which adjoins Hong Kong, these cephalometric standards may be validly applied to the 60 million southern Chinese as well as to the substantial populations of overseas Chinese for orthodontic diagnosis and treatment evaluations.