effect of beta-blockers on number of osteoblasts and osteoclasts in alveolar socket following tooth extraction in wistar rats

statement of the problem: various researchers have suggested the use of β2-adrenergic receptor antagonists in prevention or treatment of bone resorption. purpose: this study aimed to evaluate the effect of β2-adrenergic receptor antagonists on number of osteoclasts and osteoblasts involved in the healing of extraction socket of maxillary first molar in rats. materials and method: maxillary first molars of 40 rats were extracted and divided into two groups. the test group received 0.1 mg/kg propranolol intraperitoneally daily. the controls received normal saline. at days 7, 14, 21 and 28 post-extraction, 5 rats were euthanized from each group. maxillary bone was resected and the mean number of osteoblasts and osteoclasts in tooth socket was measured. results: after 1 week, the number of osteoclasts in the controls was significantly higher than the test group. a significant increase in the number of osteoclasts in both groups at week 1 was observed compared to the following weeks ( p < 0.05). the number of osteoblasts in the controls at second week reached its maximum rate but stayed constant in the 3 rd and 4 th weeks. osteoblasts in the test group increased similar to the controls but reached its maximum at 3 rd week and showed a significant increase compared to the controls ( p < 0.05). conclusion: β2 adrenergic receptor antagonists decrease the number of osteoclasts and increase the number of osteoblasts during extraction socket healing.  keywords ● osteoclast  ● osteoblast  ● propranolol  ● alveolar bone  ● rat