Cephalometric Norms of High School Students with Normal Occlusion in Hamadan( 2002)

Statement of problem: Comprehensive diagnosis is regarded as an important base for orthodontic treatment. An effective way to achieve a correct diagnosis is to compare the craniofacial skeleton of patients with normal cases in the same race through lateral cephalograms. Purpose:The present study was designed to determine the cephalometric norms of senior high school students in the city of Hamedan in 2002 and compare with results of other studies. Material & Methods: According to the normal occlusion definition 25 girls and 27 boys aged between 17 – 20 years were selected. They did not have any facial malformation and history of orthodontic treatment .Lateral cephalograms were obtained in Natural Head Position (NHP). Twenty one cephalometric variables were measured three times. Student t test was used to compare the results with other studies. Results: The mean length of anterior cranial base of girls and boys (72.5±3.7, 76.8±3.7) were significantly less than Michigan norms for girls and boys (76.9±3.9, 83.3±3.8) ( p=0.005). There was a significant tendency to more straight profile and forward rotation of mandible (88.3±4.6, 89.6±2.7) vs. Cooks´ (80.8±3.1, 82.1±2.2) (p=0.005). Linear measurements of boys were generally greater than of girls. Conclusion: It is important to consider ethnic and racial variations and sex differences in preparing problem list and treatment planning.