[Expression of vascular endothelial growth factor in periodontal tissues during orthodontic tooth movement and its role in bone remodeling].

PURPOSE: To investigate the expression of VEGF in periodontal tissues and its role in bone remodeling during orthodontic tooth movement in rats. METHODS: Rat model of tooth movement was established, and 30 rats in the experimental group were divided into 5 groups, 6 rats in each group. At 2 days, 4 days, 7 days, 14 days and 20 days, the rats were sacrificed to make periodontal tissue slice. The morphological changes of periodontal tissue were observed under H-E staining, and the expression of VEGF was semi-quantitatively analyzed by immunohistochemistry. The data were analyzed using SPSS21.0 software package. RESULTS: Expression of VEGF in normal rat periodontal tissues was very weak or without positive expression; 2 days after tooth movement, VEGF expression in periodontal tissues began to increase from seventh to fourteenth days; on the fourteenth day, the expression reached a peak; after twentieth day, the expression of VEGF decreased slightly, but still higher than the control group. The expression of VEGF was mainly found in the cytoplasm of vascular endothelial cells, osteoblasts, fibroblasts, and osteoclasts. CONCLUSIONS: Expression of VEGF may play an important role in the early remodeling of periodontal tissues during orthodontic tooth movement.