Developmental changes of mandibular permanent canines and premolars in early mixed dentition.

This study investigated the developmental changes of mandibular permanent canines and premolars in early mixed dentition using panoramic radiographs. Positions of cusps and root apices of the teeth relative to the inferior border of mandible were evaluated. The developmental stages of the teeth were divided into three stages. There were few changes in the inclination of the three teeth. The permanent canine began to erupt before stage 2 and the second premolar began to erupt after stage 2. The distance between the inferior border of the mandible and apices of the three teeth was almost fixed in early mixed dentition.