Behavior of partially formed roots of teeth submitted to orthodontic movement.

The occurrence of root resorption in orthodontically treated permanent incisors with partially formed roots was investigated using periapical radiographs taken before and after the orthodontic leveling in the mixed dentition. The mean age at the beginning of treatment was 9 years and the mean treatment time was 7.1 months. The findings showed that the orthodontic movement during root formation causes no root resorption. The longitudinal follow-up showed that incompletely formed roots developed normally.