Inhibitory effect of baicalin on orthodontically induced inflammatory root resorption in rats

Objective: This study investigated the inhibitory effect of baicalin on orthodontically induced inflammatory root resorption in rats. Methods: Forty-five male Wistar rats were randomly divided into three groups of 15 rats each. Fifty grams of force was used to establish an orthodontic tooth movement model. Baicalin (40 mg/kg) was locally injected into rats in the baicalin group at 3-day intervals; concurrently, normal saline was injected into rats in the negative control group. On the 21st day after orthodontic treatment, the tooth movement distance and root resorption area ratio were measured. Histomorphology changes were observed by hematoxylin and eosin staining and immunohistochemistry. Results: There was no significant difference in tooth movement distance between groups. The root resorption area ratio was significantly lower in the baicalin group than in the negative control group. Runx-2 expression was significantly higher in the baicalin group than in the negative control group, while tumor necrosis factor (TNF)-alpha expression was significantly lower in the baicalin group than in the negative control group. Conclusions: Baicalin inhibits orthodontically induced inflammatory root resorption by enhancing the expression of Runx-2 and reducing the expression of TNF-alpha, but does not affect tooth movement distance.