Effects of nicotine on the healing of extraction sockets in rats. A histological study.

The aim of the present study was to evaluate, histologically, the influence of nicotine on the socket healing after tooth extraction in rats. Eighty animals were divided into 4 groups of 20 rats each (2 control and 2 test groups). In the first and second test groups, the animals received one dose of nicotine hemisulfate solution once or twice daily, respectively. In the control groups, the animals received sterile saline once or twice daily. All solutions were injected subcutaneously on the dorsum of the animals for 4 weeks. The results showed that nicotine delayed alveolar healing, especially in terms of organization of connective tissue and osteoneogenesis. Angiogenesis was considerably impaired in the ossification area and in the gingival tissues as well. We concluded that the impairment of the healing of extraction sockets was found to be directly related to the drug dosage.