Protective effects of resveratrol against osteonecrosis at the extraction site in bisphosphonate-treated rats.

Resveratrol (RSV) is a phytoestrogen with a wide range of therapeutic effects, including antioxidant and anti-inflammatory effects. This study was performed to evaluate the protective role of RSV against osteonecrosis after tooth extraction in rats treated with bisphosphonates. Thirty-nine male Wistar rats, weighing 300-350 g, were divided into three groups (n = 13) according to the planned drug regimen: alendronate + dexamethasone (AL/DEX), alendronate + dexamethasone + RSV (AL/DEX/RSV), and no drugs (control group). The first and second molars of each rat were extracted and the extraction sites were analysed histologically 14 days later. The data collected were subjected to statistical analysis by means of Kruskal-Wallis, Mann-Whitney, χ2, and Fisher's exact tests using IBM SPSS software at a significance level of 0.05. The incidence of osteonecrosis was significantly lower in the AL/DEX/RSV group (P = 0.001) and control group (P = 0.041) than in the AL/DEX group, while the amount of new bone formation did not differ significantly between the AL/DEX/RSV and AL/DEX groups (P > 0.05). RSV showed a protective effect by significantly reducing osteonecrosis, which could be due to its antioxidant effects.