en ارتودنسی Orthodontics پژوهشي Research <p> <strong>Objective:</strong> To compare the magnitude of external apical root resorption (EARR) of incisors in patients undergoing the initial phase of orthodontic treatment with two sets of brackets. </p><p> <strong>Materials and Methods:</strong> According to the results of the power analysis for sample size calculation, 19 Angle Class I patients (anterior crowding: 3 to 5 mm mean age: 20.6 years) were included in the study and randomly divided into two groups: group I (n = 11, self-ligating brackets) and group II (n = 8, conventional preadjusted brackets). The degree of EARR was detected in 152 upper and lower incisors by using cone-beam computed tomography (CBCT) scans and a three-dimensional program (Dolphin 11.5, Dolphin Imaging & Management Solutions, Chatsworth, Calif) with 25% level of sensitivity. The CBCT scans were obtained before (T1) and 6 months after initiation of treatment (T2). Differences between and within groups were analyzed by nonpaired and paired t-test, respectively, with 5% significance level. </p><p> <strong>Results:</strong> Significant differences were found for both groups between T1 and T2. However, no differences in the degree of EARR were detected between the groups studied. </p><p> <strong>Conclusions:</strong> Although EARR has occurred in all teeth evaluated, the bracket design (self-ligating or conventional) did not demonstrate any influence on the results observed. </p><hr><p></p><p> <strong>Source: </strong>Angle Orthodontists </p><p><a href="http://www.angle.org/doi/abs/10.2319/080911-501.1" target="_blank"><font color="#0033ff"> Full Text</font></a></p> Self-ligating brackets, Root resorption, Cone beam computed tomography 0 0 http://idai.ir/browse.php?a_code=A-10-32-793&slc_lang=en&sid=1 Vanessa Leite 10031947532846003395 10031947532846003395 No Department of Orthodontics, University of North Paraná, Londrina, Paraná, Brazil Ana Claudia Conti accfconti@uol.com.br 10031947532846003396 10031947532846003396 Yes Department of Orthodontics, University of North Paraná, Londrina, Paraná, Brazil Ricardo Navarro 10031947532846003397 10031947532846003397 No Department of Orthodontics, University of North Paraná, Londrina, Paraná, Brazil Marcio Almeida 10031947532846003398 10031947532846003398 No Department of Orthodontics, University of North Paraná, Londrina, Paraná, Brazil Paula Oltramari-Navarro 10031947532846003399 10031947532846003399 No Department of Orthodontics, University of North Paraná, Londrina, Paraná, Brazil Renato Almeida 10031947532846003400 10031947532846003400 No Department of Orthodontics, University of North Paraná, Londrina, Paraná, Brazil