Is relevant the underestimation of irregular apical root resorption by periapical radiographs?

Abstract

Introduction: Periodic control of root resorption during orthodontic treatment is frequently made by two-dimensional radiographic examinations, in which irregular resorptions are not detected buccolingually. Aim: Quantifying the resorbed root area of incisors with irregular apical root resorption underestimated by two-dimensional radiographic methods. Materials and Methods: Cone beam computed tomography images of 18 patients whose incisors presented irregular apical root resorption underestimated by two-dimensional radiographic methods and their contralateral correspondents without resorption were evaluated. In sound incisors, a regular apical root resorption was simulated at the same height as that of the irregularly resorbed incisors. The apical and total root surface areas of the incisors with irregular root resorption and simulated regular root resorption were measured and compared. The Student´s t test for paired samples was used at a level of significance of 0.05. Results: The apical area of the incisors with irregular root resorption was significantly smaller than that of the incisors with simulated regular resorption (p<0.001). There was no significant difference in the comparison between total root surface areas (p=0.435). Conclusion: Underestimation of the irregular root resorption shown on two-dimensional images was significant when analyzing the apical area of the tooth. However, when considering the total root surface area of the tooth, which is responsible for the most part of the periodontal support, such underestimation was not significant.