Longitudinal cephalometric standards for Norwegians between the ages of 6 and 18 years

The purpose of the present study was to develop normative cephalometric standards for Norwegians from 6 to 18 years of age. The subjects in the study included 39 females and 35 males, from the Nittedal growth material. All subjects were Caucasians, and none had undergone orthodontic therapy, all had clinically acceptable normal occlusions and no apparent facial disharmony. Twenty-six measurements were analysed according to the cephalometric analysis used at the University of Oslo Department of Orthodontics. The measurements of posterior facial height, skeletal and soft tissue profiles were also included Comparisons between the dentofacial parameters of females and males at each age were performed using Student's t-test. Significant differences between females and males were present particularly at ages 12 and 15 years of age. There was a significant mean increase in NL/NSL in both sexes from 6 to 15 years of age, but more in females. There was a significant mean decrease in ML/NSL from 6 to 18 years of age, and the angle was significantly smaller in males than in females. The anterior and posterior facial height increased in both sexes from 6 to 18 years of age. The largest increase was in males. Males showed slightly more proclined upper incisors at age 9, 12, and 15 years than females. S-N-A increased more in males than females with the largest increase between 9 and 15 years of age. S-N-B increased in both sexes from 6 to 18 years of age with the largest increase in males.(ABSTRACT TRUNCATED AT 250 WORDS)