Effect of fangchinoline on root resorption during rat orthodontic tooth movement

Objective: To evaluate the short-term effect of fangchinoline, an anti-inflammatory drug widely used in Asia, on root resorption that is associated with orthodontic tooth movement. Methods: Twenty-four Wistar rats were randomly divided into 6 groups. Mesial forces of 0, 50, or 100 g were applied to the maxillary first molar of the rats in each group for 14 days by activating nickel-titanium closed-coil springs. One-half of the rats receiving each of these treatments also received injections of 200 ${\mu}L$ fangchinoline every 2 days. Finally, movement of the maxillary first molars was measured using digitized radiographs. The molars were extracted and the surfaces of the root resorption craters were recorded using a scanning electron microscope. The distance the molars moved and resorption-area ratio was measured, and results were analyzed using 2-way ANOVA tests. Results: There were no statistical differences in the distances the first molars moved under 50 or 100 g force, regardless of treatment with fangchinoline. However, the resorption area ratios were significantly smaller in those rats that were treated with both tension and fangchinoline than in those rats treated by tension alone. Conclusions: Fangchinoline reduced the resorption area ratio in rats and is therefore an important means of alleviating root resorption.