External apical root resorption generated by Forsus simultaneously with brackets vs. Xbow followed by brackets to correct Class II malocclusions

BackgroundThe objective of this study was to evaluate the frequency and severity of orthodontically induced external apical root resorption (OIEARR) on incisors following nonextraction treatment to correct mild to moderate Class II malocclusions.MethodsFrom a total of 70 consecutively treated growing patients, 32 were treated with a Forsus appliance simultaneously to brackets (FG group) and 38 were treated with a Xbow appliance followed by brackets (XG group). All patients had at least end-to-end Class II molar relationship in either side, an OJ larger than 5 mm, and an ANB larger than 4°. Both groups used the same bracket prescription and archwire sequence. A repeated-measures multiple analysis of covariance was used to assess was chosen to determine if treatment approach had any bearing on the amount of OIEARR. Factors considered were degree of OIEARR, sex, age, and their interactions.ResultsWhen comparing OIEARR between the FG and XG groups, of the teeth that experienced no resorption, 43.8% were treated with FG, whereas 56.2% were treated with XG. In teeth that experienced mild OIEARR, 41.7% were treated with FG, and 58.3% were treated with XG. In teeth that experienced moderate OIEARR, 67.3% were treated with FG, and 32.7% were treated with XG. Finally, in teeth with severe OIEARR, 42.9% were treated with FG, and 50.8% were treated with XG. There was no statistical difference noted in terms of OIEARR for patients treated with either treatment (P = 0.412). Other factors had no bearing on the results.ConclusionsFrequency and severity of incisor OIEARR were not different between the two treatment approaches.