A radiographic evaluation of apical root resorption following intrusion therapy

Aim: The aim of the present study was to evaluate whether patients treated with an additional upper utility arch show higher amounts of root resorption than patients treated with a straight-wire technique. Materials and methods: 67 patients were included in this study. 29 of them (group 1) were treated with an additional maxillary utility arch within the straight-wire therapy (intrusion 15gm). 38 patients (group 2) were treated with a straight-wire fixed appliance. The amount of apical root resorption of the maxillary central incisors was determined for each patient by subtracting the post-treatment tooth length from the pre-treatment tooth length measured directly on cephalograms. Results: Root shortening of the maxillary central incisors was found to average 1,7mm after using an additional maxillary utility arch (group 1) for 5 months (average) and a treatment time of 23,8 months. Root shortening was found to average 0,7 mm after a treatment time of 19,8 months (average). The amount of root resorption between the two orthodontic techniques was compared by means of the student-t-test, showing to be significant. Conclusion: In the present study, it was found that intrusion with the utility arch type of technique increases the amount of root resorption for the central maxillary incisors. The average amount of root resorption in both groups show no clinical relevance. Keywords: apical root resorption, intrusion, maxillary central incisor, cephalogram