Penyerapan akar gigi apeks luaran hasil rawatan ortodontik pada enam dan 12 bulan

External apical root resorption (EARR) is one of the negative effects of orthodontic treatment apart from dental trauma. The objectives of this study were to observed the relationship between history of trauma and the occurence of EARR and also to compare the severity of EARR between traumatized and nontraumatized teeth during six and 12 months of orthodontic treatment. The sample of study was maxilla central incisor from 23 subjects (8 male and 15 female age 12 to 26 years old) in which 19 with traumatized teeth (without root resorption) and 27 nontraumatized teeth. Orthodontic treatment used 0.014", 0.018" and 0.018" x 0.025" NiTi archwires for the first six months. After six months, orthodontic treatment was continued using 0.019" x 0.025" stainless steel arch wire until the treatment reached one year. EARR was measured using cone beam computed tomography (CBCT) images that was taken before (X-0), after six months (X-6) and after 12 months (X-12) of orthodontic treatment. Root resorption was calculated by substracting tooth length at X-6 and X-12 with tooth length at X-0. The incidence of EARR in traumatised and non-traumatised teeth group were each 89.5% and 77.8%, respectively (root resorption less than 2 mm) after six months of orthodontic treatment. After 12 months of orthodontic treatment, all teeth showed EARR. There is no significant difference in the occurence of EARR between traumatized and nontraumatized teeth (p>0.05). In this study, traumatized and nontraumatized teeth develop EARR at the same rate after six and 12 months of orthodontic treatment. Hence, it is safe to do an orthodontic treatment to patients with dental trauma history.