Root resorption after orthodontic treatment of traumatized teeth.

This study concerns the frequency and degree of root resorption in traumatized incisors that have been treated orthodontically. The subjects were twenty-seven patients (fifteen boys and twelve girls) with fifty-five traumatized incisors; fifty-five consecutive patients without traumatized teeth served as controls. All the control patients were treated with extraction of four first premolars and a fixed appliance (thirty-three with an edgewise and twenty-two with a Begg appliance). Signs of root resorption were registered with index scores from 0 to 4 (Fig. 1). The degree of root resorption in traumatized teeth was compared to that in the uninjured control teeth in the same patient and in the patients without trauma. Neither the intraindividual nor the interindividual comparisons support the hypothesis that traumatized teeth have a greater tendency toward root resorption than uninjured teeth. Root resorption (scores 2 to 4) was found in 51 percent of the traumatized incisors, in 43 percent of the incisors treated with edgewise appliances, and in 48 percent of those treated with Begg appliances. Traumatized teeth with signs of root resorption prior to orthodontic treatment may be more prone to root resorption during treatment.