to critically analyse the available scientific literature radiographically comparing the incidence of orthodontically induced external apical root resorption (OIEARR) in human root-filled and vital teeth. Several electronic databases (MEDLINE, PubMed, EMBASE, Scopus, Web of Science, CINAHL, and the Cochrane Database of Systematic Reviews and Google Scholar) were searched without limits, with the assistance of a senior librarian specialized in Health Sciences database searches. Human, in vivo studies that radiographically compared root resorption following fixed orthodontic treatment in root-filled and vital teeth were selected for full article review. Additionally, the bibliographies of the finally selected articles were hand searched to identify any relevant publications that were not identified by electronic searches. The lowest levels of evidence accepted for inclusion were case controls or cohort studies. Two authors independently reviewed and extracted data from selected studies. A total of 165 original articles were identified from electronic database searches and 2 from hand searches. Once selection criteria were applied, only four articles met all inclusion criteria, and individual analysis of the selected articles was undertaken. Based on available evidence, root-filled teeth do not appear to be more susceptible to OIEARR than their analogous vital teeth.