Mandibular bone loss in ewe induced by hypothalamic-pituitary disconnection

Purpose: It is supposed that the demographic change will lead to an increase in patients with impaired alveolar bone conditions. Large animal models are of particular interest in this context as they are suitable for developing and testing new dental implants. Recently, we demonstrated that surgical hypothalamo–pituitary disconnection (HPD) causes a pronounced low-turnover situation leading to cortical and trabecular bone loss in sheep. In this study, we aimed to investigate the influence of the HPD procedure on the alveolar bone. Methods: Ten adult Merino ewes were randomly assigned to two groups: Control and HPD. After 6 months, we analysed the cortical and trabecular bone of all mandibles by histomorphometry and high-resolution peripheral quantitative computed tomography (HR-pQCT). Results: HPD ewes showed a significant decrease in cortical thickness by ~20%, a significant increase in cortical porosity by ~20% and a significant decrease in bone volume by ~30% in comparison with Control ewes. Conclusion: Our results underline the importance of central regulatory mechanisms of bone turnover. However, further studies are needed to understand these central regulatory elements of bone turnover in detail and to judge the value of the HPD sheep for dental research.