Inhibitory effects of resveratrol on orthodontic tooth movement and associated root resorption in rats.

Abstract

OBJECTIVE\nTo investigate the effect of resveratrol (RSV) on orthodontic tooth movement (OTM) and orthodontic induced root resorption (OIRR) in rats.\n\n\nMETHODS\nThirty-six male Wistar rats used in this study were randomly divided into three groups of 12 animals each. All test subjects underwent a 50\u202fg orthodontic force each, generated from a nickel-titanium closed-coil spring. The control group were fed carboxymethylcellulose (CMC) while rats in other two groups were fed 5\u202fmg/kg/d RSV or 10\u202fmg/kg/d RSV (dissolved in CMC). After 14 days of OTM, all rats were sacrificed, after which each group was randomly divided into two subgroups (6 test subjects in each subgroup). One subgroup was used to measure the amount of OTM and assessed by hematoxylin and eosin (HE) staining, tartrate-resistant acid phosphatase (TRAP) staining, and immunohistochemistry staining of Receptor Activator of Nuclear Factor-κ B Ligand (RANKL), Osteoprotegerin (OPG), Runt-related transcription factor 2 (RUNX2), as well as Osteocalcin (OCN). The second subgroup was used to analyze OIRR via scanning electron microscopy.\n\n\nRESULTS\nCompared with the control group, the RSV groups showed a significant decrease in the distance of OTM and the OIRR ratio (p＜0.05). The number of TRAP positive osteoclasts and the expression of RANKL in periodontal tissue of the RSV groups were significantly inhibited (p＜0.01) while the expression of OPG, RUNX2, and OCN were remarkably promoted (p＜0.05). The effect of 10\u202fmg/kg/d RSV group was more obvious than that of 5\u202fmg/kg/d RSV group (p＜0.05).\n\n\nCONCLUSIONS\nRSV could reduce the extent of OTM and root resorption areas.