Root resorption associated with maxillary buccal segment intrusion using variable force magnitudes: A randomized clinical trial

Objectives: To compare the root resorption resulting from miniscrew-supported maxillary posterior dentoalveolar intrusion using two different force magnitudes. Materials and Methods: Adult patients with skeletal open bite, indicated for maxillary posterior dentoalveolar intrusion, were recruited and randomly assigned to the comparison or intervention groups. The comparison group involved applying 200 g of intrusive force per segment, which measured 20 g per root, while this force was 400 g per segment in the intervention group, measuring 40 g per root. Results: Twenty participants were included in the final analysis after 2 patients dropped out, 1 in each group, to end up with 10 subjects (200 roots) per group. There was statistically significant root resorption of 0.84 +/- 0.96 mm and 0.93 +/- 1.00 mm in the comparison and the intervention groups, respectively. However, there was no statistically significant difference between the groups. Conclusions: Root resorption inevitably took place in association with orthodontic intrusion. However, increasing the magnitude of the intrusive force did not increase the amount of root resorption, either statistically or clinically. (Angle Orthod. 2021;91:733-742.)