Abstract
This study was designed to measure the angle between the occlusal plane and labial or buccal surface of deciduous teeth in the lateral segment. The data were obtained from 109 dental casts of 3-year-old children with normal occlusion.
The bases of the casts were kept parallel to th e occlusal plane that was established by including the tips of the mesio-buccal cusp of upper right and left second deciduous molars and the incisal edge of the upper left deciduous central incisor.
The standardrized photographs were taken 700 mm in front of the ca s t with Micro-Nikkol 105 mm lens and flash.
We Then measured t h e angle of inclination of the labial or buccal surface of the deciduous teeth in the lateral segment to the occlusal plane on the photographs.
The results were as follows:
1. In maxilla, the average of the angles of inclination were: 70.3° in left deciduous cuspid and 69.1K in right; 74.0K in left first deciduous molar and 72.8K in right; 72.4° in left second deciduous molar and 71.0° in right.
2. In mandibular, the average of the angles of inclination were: 70.6° in left deciduous cuspid and 71.8° in right; 55.1° in left first deciduous molar and 54.8° in right; 49.1° in left second deciduous molar and 49.2° in right.
3. The angle of inclination between left and right teeth revealed a positive correlation, and it also revealed to be nearly almost symmetrical in both sides.
