Abstract
The angle of the auricular long axis line to the nasal dorsal line was measured in 305 male and female Japanese aged 5, 10 or 15 years in order to obtain the standards for the inclination of the auricle in otoplasty. In the observation, the head of a subject was confirmed not to lean toward either right or left and then the right side view of the head was photographed at a distance of 150 cm. In the photographs the line connecting the anterior border of the helix and the anterior border of the tragus was defined as the auricular attaching line and used as a standard line in the measurement. In addition, the length inside the auricle of the perpendicular line to the auricle attachment line was defined as the auricular apse line.
The point at which the line connecting the right and left inner ocular angles intersects the dorsum of the nose was defined as the nasal point and the highest point of the dorsum of the nose as the nasal cristate point. The line connecting both points was called as the nasal dorsal line. Each of the three lines was extended, and the intercrossing angle between the auricular attaching line and the nasal dorsal line, that between the auricular attaching line and the auricular long axis line and that between the auricular long axis line and the nasal dorsal line were called as X, Y and Z, respectively and measured with a protractor. The results obtained in the current study were analysed together with out previous results in young Japanese which demonstrated that the long axis line dose not run parallel to the nosal dorsal line in 20-year-old men and women. The mean and the standard deviation of the measurements of angle Z are as follows :
Males 5 years of age : 16.0°±5.74
10 years of age : 15.8°±7.43
15 years of age : 18.4°±6.10
20 years of age : 16.0°±4.1
Females 5 years of age : 15.8°±6.43
10 years of age : 17.0°±5.02
15 years of age : 16.1°±6.37
20 years of age : 14.6°±6.1
The results reveal that the auricular long axis line does not run parallel to the nasal dorsal line in 5-, 10- and 15-year-old Japanese males and females as in 20-year-old men and women. The auricular long axis line was located ahead the line parallel to the nasal dorsal line and with a gradient to the aforementioned angle. In addition, there was no significant sex difference in the angle at the age of 5 years and it reached the maximum at the ages of 10 and 15 years in females and males, respectively and decreased with age thereafter.
