Effects of intermittent parathyroid hormone treatment on new bone formation during distraction osteogenesis in the rat mandible.

ABSTRACT

OBJECTIVE: The effect of intermittent parathyroid hormone (PTH[1-34]) treatment on bone regeneration in a rat model of mandibular distraction was evaluated using microcomputed tomography. STUDY DESIGN: After a 5-day latency period, mandibles of 18 rats were distracted at 0.2 mm/12 hours for 10 days, and rats in the PTH and control groups received subcutaneous injections of PTH(1-34) at a dosage of 60 µg/kg body weight or a vehicle only, respectively, 3 times a week. The animals were humanely killed after 10 days of distraction and after 1 week and 3 weeks of consolidation. RESULTS: In reconstructed 3-dimensional images of the distracted mandible, mean bone volumes of the desired region of interest in the PTH group were significantly larger than those in the control group at all time points. CONCLUSIONS: Intermittent PTH(1-34) treatment enhances new bone formation during mandibular distraction in a rat model, and it may be effective for shortening the consolidation period.