External root resorption in orthodontics: avoiding high risk teeth. A case report.

External root resorption is one of the most exasperating and least understood clinical problems in orthodontics. Numerous studies have been conducted, attempting to establish the factors causing root resorption of permanent teeth. Considerable variation exists however, in the extent and distribution of root resorption, seen in the orthodontic treatment of apparently similar cases. After an excellent review of the literature, Brezniak and Wassertein (1993) concluded that the most significant disgnostic aid in predicting whether root resorption would occur during orthodontic treatment, is the radiographic evidence of root resorption before treatment. A case is reported, describing the dilemma of orthodontically treating a patient, who had previously experienced trauma to the upper right central incisor, leading to external root resorption.