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OBJECTIVES To investigate the effects of intermittent parathyroid hormone on cementoblast-mediated periodontal repair in the context of orthodontic induced root resorption. MATERIALS AND METHODS The rat model of orthodontic induced root resorption was established. Sixty rats were randomly allocated into the experiment group (n=30) and the control group (n=30), either receiving a daily subcutaneous injection of recombinant human PTH or placebo vehicle. Enzyme linked immunosorbent assay, Micro-computed tomography, hematoxylin and eosin staining, and immunohistochemistry staining were performed to detect the periodontal repair. In vitro, OCCM-30 cells were exposed to intermittent PTH (incubated with PTH for the first 6 hours in each 24-hour cycle). After three cycles, flow cytometry assay, alkaline phosphatase staining, and Alizarin red staining were performed. Quantitative real-time polymerase chain reaction and western blotting were employed to further determine the effects of intermittent PTH. RESULTS Intermittent PTH-responsive repair enhancement was detected with the expression of bone sialoprotein, osteocalcin, collagen-1, and alkaline phosphatase significantly upregulated. Increased expressions of cementoblastic proteins were positively correlated to cycles of PTH administration. The proportion of cementoblasts in S and G2/M phases was increased; namely, intermittent-PTH promoted cementoblast cell proliferation. CONCLUSIONS Intermittent parathyroid hormone administration promotes cementoblast-mediated cementogenesis during periodontal repair in a time-dependent manner.