[Apical root resorption of maxillary central incisors following orthodontic treatment].

This research shows the relationship between orthodontic treatment and apical root resorption. The latest edgewise appliance with a pre-adjusted bracket (Alexander method) was used in the present experimentation. Examination by roentgen cephalometry and intraoral radiography was performed before and after the maxillary central incisors had been moved orthodontically. The conclusion is that there was no significant difference among the grade 0, 1, 2 and 3 of apical root resorption in the change of long axis inclination of the maxillary central incisors. But there was a significant difference among the grade 0, 1, 2 and 3 of root resorption in the distance of the apical root movement. The most apical root resorption was observed when the apical root was moved lingually.