Use of Psidium guajava fruit suspension may prevent treatment relapse following orthodontic tooth movement in Wistar rat model.

To investigate the effect of Psidium guajava fruit suspension in preventing orthodontic treatment relapse in a Wistar rat model. Twenty-four male Wistar rats (aged 8-12 weeks) underwent orthodontic treatment on the left maxillary side for 48 days. After space creation, orthodontic appliances were removed, and a 35-day retention phase was initiated. Meanwhile, the rats were randomly allocated to two groups. The control group received normal saline, and the intervention group received a suspension of 250 mg/kg P. guajava via oral gavage. After retention, the resin retainers were removed to allow for a 7-day relapse phase. Polyvinyl siloxane impressions were obtained at the start (T0) and end (T1) of the relapse phase and scanned for analysis using OrthoCad software. Of the 24 rats initially recruited, 20 rats successfully completed the experiment and were included in the statistical analysis. The mean orthodontic tooth movement (T0) and relapse measurements (T1) in the intervention group were 0.570 ± 0.125 mm and 0.515 ± 0.094 mm, respectively. In the control group, the corresponding mean values were 0.630 ± 0.194 mm and 0.410 ± 0.204 mm, respectively. The intervention group demonstrated significantly lower mean orthodontic relapse (T1-T0) than that of the control group (-0.055 ± 0.089 mm and -0.220 ± 0.058 mm, respectively, P < 0.001). Orally administered P. guajava fruit suspension may reduce orthodontic relapse and improve treatment outcomes. Further studies are required to validate these findings and elucidate the underlying mechanisms before considering human trials.