Role of Transforming Growth Factor Beta 1 in Reducing Orthodontic Relapse: Rabbit Model Study

Abstract

Background: This study attempted to evaluate clinically and histologically the effect of local injection of transforming growth factor beta 1 (TGFβ1) on the rate of orthodontic relapse. Methods: 24 male albino rabbits were used, that grouped randomly into two groups (12 rabbits in each): positive control and TGFβ1 groups. Each group was further divided into 3 subgroups with 4 rabbits in each. Modified orthodontic appliances were cemented to the mandibular central incisors and tooth movement was carried out for 2 weeks, followed by a retention period for 3 weeks where positive control and TGFβ1 groups received local injections of phosphate buffer saline and TGFβ1 solutions, respectively, then the teeth allowed to relapse after removing the appliances for 20 days. The relapse was estimated clinically. Histological and immunohistochemical analyses were carried out following the completion of the experiment. Result: The TGFβ1 group showed a significantly lower rate of relapse than the positive control group. Histologically, during the relapse period, a significant increase in the number of osteoblasts, a decrease in the number of osteoclast, which was also confirmed by immunohistochemical analyses and a lesser PDL width was seen in TGFβ1 group when compared to the positive control group. local injection of TGFβ1 can significantly reduce the orthodontic relapse in the rabbit model.