Intermittent Administration of Parathyroid Hormone for Orthodontic Tooth Movement in Mongrel Dogs: Preliminary Study

ABSTRACT

Purpose@#This study investigated the orthodontic tooth movement after weekly parathyroid hormone (PTH) injection in mongrel dogs and analyzes bone formation activity on the tension and pressure sides of the tooth movement in mongrel dogs. @*Materials and Methods@#Three mongrel dogs were used in this study. The first premolar was extracted and orthodontic force using 150 g of closed coil springs between the canine and second premolar was applied. The low-dose PTH group (PTH_1) and high-dose PTH group (PTH_2) received weekly injections of 1.61 μg/kg and 3.23 μg/kg of PTH, respectively. The control group received weekly injections of 1 ml of saline. Clinical, histomorphometric analysis were carried out.Result: The orthodontic tooth movement was greatest in the PTH_2 group and the lowest in the control group. Fluorescence staining images showed higher bone remodeling on the tension side of the tooth movement in the PTH_1 and PTH_2 groups. PTH_2 group showed a thicker labeling band than the PTH_1 group. PTH_2 group showed the highest mineral apposition rate and bone formation rate, followed by the PTH_1 group and the control group. @*Conclusion@#Weekly intermittent PTH injection, especially in the short-term and at higher doses with orthodontic force, successfully increased orthodontic tooth movement and bone remodeling in mongrel dogs.