Avaliação de reabsorções radiculares apicais externas decorrentes de movimentação ortodôntica em radiografias periapicais com registro a posteriori

O objetivo deste estudo foi quantificar a reabsorcao radicular apical externa em individuos submetidos a tratamento ortodontico e correlacionar a reabsorcao radicular com possiveis fatores predisponentes. A amostra incluiu 79 individuos, com idade media de 13,7 anos e dividida em 2 grupos, de individuos tratados sem e com exodontia dos primeiros pre-molares superiores. Foram selecionadas as radiografias periapicais dos incisivos centrais superiores, obtidas no inicio e no final do tratamento ortodontico. As radiografias foram digitalizadas e inseridas no programa Regeemyri u Image Registration and Mosaicking v.0.2.43-RCB (DPI-INPE, Sao Jose dos Campos, SP, Brazil) e procedidos os registros a posteriori (correcao de diferencas de projecao geometrica, densidade e contraste entre as duas radiografias). As mensuracoes dos incisivos centrais superiores, foram realizadas nas imagens referencia (pretratamento) e na versao registrada (pos-tratamento), no programa UTHSCSA Image Toolri (University of Texas Health Science Center at San Antonio), obtidas em pixels e convertidas em porcentagem. Os resultados mostraram que ocorreu reabsorcao radicular estatisticamente significante em ambos os grupos, com maior reabsorcao no grupo com exodontia (p0,05). O periodo do tratamento foi significantementemaior no grupo com exodontia e as reabsorcoes radiculares foram tambem maiores no grupo tratado com exodontias (p The aim on this study was to quantify the external apical root resorption in individuals submitted to orthodontic treatment and to correlate the root resorption with the possible predisposing factors. The sample comprised 79 individuals (mean age 13,7 years) divided into two groups: individuals treated with and without extractions of the maxillary first premolars. Periapical radiographs of maxillary central incisors obtained in the beginning and in the end of the orthodontic treatment were selected. Theradiographs were digitized and imported to Regeemyri u Image Registration and Mosaicking v.0.2.43-RCB (DPI-INPE, Sao Jose dos Campos, SP, Brazil) for image registration a posteriori (correction of geometric, density and contrast differences between two images). The maxillary central incisors were measured in the reference (pre-treatment) and registered (post treatment) images using UTHSCSA Image Toolri(University of Texas Health Science Center at San Antonio). The measurements were obtained in pixels and converted to percentage.Statistically significant root resorption was found for both groups, but it was greater for the extraction group (p0,05). The treatment duration was found to be statistically higher for the extraction group as wellas the root resorptions (p