Advisory Committee Chair
Advisory Committee Members
Chung How Kau
Date of Award
Degree Name by School
Master of Science in Dentistry (MScD) School of Dentistry
The main goals of orthodontic treatment are to achieve a harmonious dentalocclusion and enhance the patient’s dentofacial appearance. External Apical Root Resorption (EARR) is a side effect of orthodontic treatment1. It results in the permanent loss of tooth structure from the root apex2. EARR is a multifactorial condition which includes patient related and treatment related risk factors. Patient-related factors include genetics, severity of malocclusion, tooth-root morphology, systemic factors, density of alveolar bone, root proximity to cortical bone, previous exposure to trauma, patient age and sex. Orthodontic treatment related risk factors include treatment duration, amount of force and mechanics used, direction of tooth and apex movement3. 1-2 mm of apical root resorption during orthodontic treatment is considered to be clinically important5. However, the factors contributing to EARR are not well documented. Objective: To determine the prevalence of apical root resorption in the Asian population in Alabama and evaluate the effects of treatment on root integrity. Methods: This study comprised 137 Asian patients treated at the orthodontic clinic of the University of Alabama at Birmingham School of Dentistry. The initial and final records of these patients were examined and the panoramic and cephalometric radiographs were used in the study . Exclusion criteria included unclear radiographic references, open root apices, iv history of dental trauma or history of craniofacial syndromes, and previous orthodontic treatment. Crown to root ratios were used to measure the root resorption using a technique developed by Lind24 and then modified by Holtta et al.18. To examine whether root resorption on the maxillary incisors had occurred, we used Dolphin Imaging software (Chatsworth, CA) that enabled the pre and post treatment radiographs to be digitized. Results: The prevalence of moderate root resorption with equal or greater than 20% loss of root structure in our sample was 22.6%. The lateral incisors showed a greater prevalence for EARR than central incisors. In our study, EARR was significantly associated with the Class III dental classification and an extraction treatment plan. Conclusions: Our results suggested that care must be taken during orthodontic treatment of Asian patients with a Class III malocclusions that may require an extraction treatment plan.
Aswad, Najd, "External Apical Root Resorption In Asian Orthodontic Patients In Alabama" (2021). All ETDs from UAB. 688.