The mechanism of action of the bisphosphonate containing nitrogen (nBPs) consists in inhibit bone resorption due to their interference on osteoclasts function, which becomes highly mineralized and less reactive, facilitating the onset of osteonecrosis (ON) of jaws when associated to invasive procedures in the oral cavity. Nevertheless, studies have demonstrated that besides its direct interference on bone dynamics, the immunological system also is compromised by chronic administration of nBPs, and ON onset does not depend on bone quality only. The aim of the present study is to analyze the inflammatory process during alveolar repair of 129/Sv-WT in comparison to 129/Sv 5-LOKO mice, which presents an osteoporotic skeleton phenotype due to the lack of 5-leucotriene enzyme, with and without the administration of zoledronate (ZL). Eighty male mice will be used, presenting 4-6 weeks of age, compounding the following groups: WTc and 5-LOKOc - treated with sterile 0.9% saline solution, via IP, and WTzl e 5-LOKOzl - treated with 0.5 mg/Kg of ZL, via IP. Both solutions will be administered once a week. After the fourth administration, the right upper incisors will be extracted. After 3, 7, 14, and 30 days, the animals will be euthanized and the right maxillae will be removed, in order to permit the analysis of the extracted sockets. Histological slices will be prepared and stained with hematoxylin and eosin, for the description of the histological events occurring in the specific time points, and histomorphometry considering: collagen fibers, fibroblasts, blood vessels, bone matrix, osteocytes and lacunae, osteoblasts, leukocytes, along with immunohistochemistry labeling for COX-2 and 5-LO. Results from histomorphometry and immunolabeled cells will be counted and the results will undergo statistical treatment.
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