Analysis of the root resorption after the orthodontic treatment of upper incisors retraction between adults and adolescents

Objective To investigate the difference of the root resorption after the orthodontic treatment of upper incisors retraction between adults and adolescents.Methods seventy-nine patients (38 adults,41 adolescents) with maxillary protrusion treated with extraction by straight wire appliances were selected.Root morphology were observed and the length of root and crown were measured in the panoramic radiographs before and after treatment to obtain the qualitative and quantitative data of root resorption of the upper incisors.The data were analysed by SPSS11.0 software package.Results After treatment,root resorption of upper central incisors in adults was more severe than that of lateral incisors And root resorption of upper central incisors in adults was more severe than that in adolescents.These differences were statistically significant (P0.05).The grade of root resorption of upper central incisors of adults was different from that of adolescents (P0.01).Conclusion Adults suffer more severe root resorption in upper central incisors after the orthodontic treatment of upper incisors retraction.