Pulpal response to orthodontic tooth movement in adolescents: a radiographic study.

The purpose of this study was to examine the effect of routine orthodontic treatment on the pulp and periodontal ligament. In a group of adolescent patients who were treated consecutively, radiographs were taken before orthodontic intervention, at the end of retention, and approximately 5 years out of retention. These were compared with radiographs taken at comparable time intervals of a group of patients who had not received orthodontic treatment. Damage to the pulp and the periodontal ligament similar to that seen after traumatic injury was observed only occasionally. A narrowing of the pulp canal was observed from before to after appliance therapy and during the follow-up period in the experimental group. A narrowing of the pulp canal was also seen in the untreated group. Thus this narrowing was interpreted as a normal aging process.