Is Orthodontic Treatment a Risk Factor of Cervical Root Resorption? A Systematic Review

Cervical root resorption is an uncommon, aggressive form of external resorption that occurs on the root surface of a permanent tooth and presents clinically as a characteristic pinkish discoloration of the tooth. The cause of cervical root resorption is poorly understood, and it has been suggested that orthodontic treatment may play a role in causing this pathological condition. The aim of this systematic review was to investigate whether orthodontic treatment could be considered as a risk factor of cervical root resorption in patients who had undergone fixed appliances therapy. A comprehensive electronic and manual search was conducted in four databases and six journals without any limitations on year of publication. A customized data extraction form was used to retrieve relevant information from each eligible study. Risk of bias was assessed using the Cochrane risk of bias tool (RoB 2) and the risk of bias in nonrandomized studies of interventions tool (ROBINS-I). The quality of evidence was assessed using the grading of recommendations, assessment, development, and evaluation (GRADE) approach. Two randomized clinical trials (RCTs) and one cohort study were included in the review. Risk of bias was assessed as high for both RCTs and critical for the cohort study. Conflicting results were reported by the studies included in this review. Both RCTs reported significant differences between orthodontically moved teeth and teeth that were not moved, while the cohort study reported a lack of association between fixed orthodontic treatment and cervical root resorption. Quality of evidence provided by this review was judged to be of very low quality. Orthodontic treatment may have potential in inducing cervical root resorption; however, due to the high risk of bias of the included studies and their conflicting findings, better-quality studies are needed to make definitive conclusions.