Objectives: The objectives of this study were to compare the amount of apical root resorption after orthodontic treatment with Herbst and Twin Block Bite Jumping screw (TBBJS) functional appliances, also to determine the prevalence of root resorption in the maxillary and mandibular incisors and the dental arches. Methods: 30 patients were divided into two groups 15 patients each. The first group was treated with Herbst appliance and the second group with TBBJS appliance. After treatment, periapical radiographs were obtained of the maxillary and mandibular incisors with the long-cone paralleling technique. Root resorption was scored according to the method of Levander and Malmgren. Results: Results of the Mann-Whitney U test showed that there were no statistically significant differences between the Herbst and TBBJS groups. The amounts of root resorption were predominantly small. The prevalence of resorption for the incisors was greatest for the maxillary central, followed by the maxillary lateral, mandibular central, and mandibular lateral incisors. Conclusions: There was no difference in the amount of root resorption between the Herbst and TBBJS groups with more resorption in maxillary arch than mandibular arch.