Comprehensive Cephalometric Analyses of 10 to 14-Year Old Southern Chinese

Aims: (Part 1) To review the orthodontic literature and assess which cephalometric methods were the most frequently used, and (Part 2) provide comprehensive cephalometric reference values for 10 to 14-year old southern Chinese. Materials and Methods: (Part 1) The cephalometric methods used in the orthodontic literature over a ten-year period (1999-2008) were investigated. (Part 2) The material comprised lateral cephalometric radiographs of a random sample of 200 males and 205 females 12-year old southern Chinese in Hong Kong. The radiographs were digitized twice with the Computer Assisted Simulation System for Orthognathic Surgery (CASSOS) program. Referenced values for 10-, 11-, 13and 14-year old were obtained by extrapolation of data from measurements of templates of longitudinal sample of Swedish. Results: (Part 1) The four most frequently used cephalometric methods were those devised by Björk, Jacobson, Pancherz and McNamara. (Part 2) Reference population values for those four methods of 12-year old southern Chinese children were collected from three of our previous publications, and for the McNamara analysis expanded to include 10 to 14-year old children. At the age of 12-year there were statistically-significant gender differences for the majority of the cephalometric variables based on linear measurements, varying from -0.4 to +0.8 standard deviation (SD)-scores, and about half of the angular measurements, varying from -0.4 to +0.4 SD-scores. Conclusion: Four cephalometric methods presented over a 10-year period were more commonly used than the other cephalometric methods. The use of specific cephalometric standards of those four methods for southern Chinese, separate for gender, seem to be justified.