Objective To test the diagnostic accuracy of qualitative and semi-quantitative evaluations on root resorption associated with orthodontic force（RRAOF） using orthopantomogram（OPG） and periapical film, through comparing with assessments with cone beam computed tomography（CBCT）, which is considered as the gold standard. Methods Before and after treatment, OPG, periapical film, CBCT images of 121 upper anterior teeth in 32 orthodontic patients were obtained. Blind evaluation of RRAOF was performed according to Levander and Malmgren’s method by three trained radiographers through examining three kinds of images of these teeth. The diagnostic accuracy of qualitative and semi-quantitative evaluations on RRAOF using OPG and periapical films were test through comparing with assessments with CBCT, which was considered as the gold standard. Results To the same sample, the RRAOF qualitative and semi-quantitative diagnostic classification Rults of OPG and periapical films compared with CBCT were significant differences（P
