With a view to making a comparative study of the thickness of the cortical bone at the mandibular angle in school-age children and in children at puberty, a total of 80 children,40 school-age children from 7 to 12 years old and 40 children at puberty from 13 to 18 years old, who came for examination to the outpatient ward, Department of Pediatric Dentistry, Kyushu Dental College, were used as the subjects. The cortical bone at the mandibular angle was measured on panoramic radiographs.
The results were as follows:
1. The averages were 0.90±10.23 mm for school-age children and 1.09±0.34 mm for children at puberty. The averages based on sex of the thickness of the cortical bone at the mandibular anglc were 0.88±0.20 mm for boys and 0.93±0.25 mm for girls of school-age children, and 1.07±0.41 mm for boys and 1.12±0.26 mm for girls at pubcrty. At the side, the averages were 0.87±0.21 mm for the left side and 0.93±0.22 mm for the right side of school-age children, and 1.14±0.35 mm for the left side and 1.05±0.27 mm for the right side of children at puberty.
2. No significant differences were found in the t-test based on sex, age, or side. Based on age, children at puberty showed significantly higher values than school-age children.
3. The correlation coefficient between age and thickness of cortical bone at the mandibular angle was r=0.809.