Abstract
OBJECTIVES: The objectives are to assess the severity and frequency of clinically relevant external apical root resorption (EARR) ≥ 2 mm during orthodontic treatment with Damon passive self-ligating and Victory conventional standardised fixed appliance systems and to evaluate the relevance of intermediate radiographic examinations for early detection and prevention of severe EARR. MATERIALS AND METHODS: Adolescents aged 12-17 years with crowded and displaced teeth planned for non-extraction treatment were recruited from three orthodontic clinics. Participants were randomly allocated in a 1:1 ratio to treatment with either Damon Q (n = 35) or Victory (n = 40) using stratified blocks, with allocation concealed. EARR was assessed for all roots from incisors to molars using multiplanar reconstruction in cone beam computed tomography (CBCT) images acquired from various CBCT machines before, during and after treatment. RESULTS: Sixty-two patients were included in the EARR analysis. The upper incisors were the most affected tooth group, with mean EARR values of 0.20 mm for Damon and 0.51 mm for Victory (NS, alpha 1%). The frequency of clinically relevant EARR in this tooth group was 5.0% for Damon and 7.2% for Victory (NS, alpha 5%). Only one case with clinically relevant EARR after treatment was identified in the intermediate radiographic examinations. CONCLUSIONS: The overall severity and frequency of EARR were below clinically relevant levels in both treatment groups. The results strengthen the evidence that routine intermediate radiography appears to be of limited relevance for early detection and prevention of severe EARR in non-extraction treatments for adolescents with crowded teeth. TRIAL REGISTRATION: ClinicalTrials.gov: NCT05664282.