The purpose of this study is to examine and compare the amount of external apical root resorption (EARR) in incisors observed after orthodontic treatment using fixed orthodontic appliances (FOA) or clear aligners (CAT). The systematic review was carried out adhering to PRISMA guidelines. The review included retrospective studies and randomized control trials, which performed 2D panoramic radiographs, periapical radiographs, and cone beam computed tomography to evaluate EARR levels in anterior teeth after orthodontic treatment with CAT and FOA. The focused question for the review was raised using the PICO model: does CAT induce lower levels of EARR compared to fixed orthodontic appliances The review was comprised of six articles. Five of the included publications were retrospective cohort studies and one was a randomized clinical trial. Meta-analysis revealed that CAT had a lower amount of EARR than FOA (SMD = 0.76, 95% CI = -1.17, -0.34; p<0.00001). The subgroup analysis concluded that EARR was statistically significantly lower in maxillary central incisors. (SMD = -0.40, 95% CI = -0.70, -0.10; p = 0.009), maxillary lateral incisors (SMD = -0.65, 95% CI = -0.98, -0.32; p = 0.0001) and in mandibular central incisors (SMD = -0.40, 95% CI = -0.65, -0.16; p = 0.001). Based on this meta-analysis, CAT appears to be superior to FOA in terms of EARR in the anterior teeth region.
