Mandibular bone loss in ewe induced by hypothalamic-pituitary disconnection

Area of Science:

• Bone Biology and Endocrinology
• Dental Implantology Research
• Large Animal Models in Regenerative Medicine

Background:

• Demographic shifts predict increased prevalence of impaired alveolar bone conditions.
• Large animal models are crucial for developing and testing novel dental implants.
• Previous research established that surgical hypothalamo-pituitary disconnection (HPD) induces low-bone-turnover and bone loss in sheep.

Purpose of the Study:

• To investigate the specific effects of the hypothalamo-pituitary disconnection (HPD) surgical procedure on alveolar bone characteristics in a sheep model.
• To assess the potential of the HPD sheep model for studying conditions related to impaired alveolar bone.

Main Methods:

• Ten adult Merino ewes were divided into two groups: Control and HPD.
• After a 6-month period, mandibular bone was analyzed using histomorphometry.
• High-resolution peripheral quantitative computed tomography (HR-pQCT) was employed for detailed bone analysis.

Main Results:

• HPD ewes exhibited a significant ~20% reduction in cortical thickness compared to controls.
• Cortical porosity significantly increased by ~20% in the HPD group.
• Bone volume in the HPD group showed a significant decrease of ~30%.

Conclusions:

• The findings underscore the critical role of central regulatory mechanisms in controlling bone turnover.
• The HPD procedure in sheep leads to significant detrimental changes in alveolar bone structure.
• Further research is necessary to elucidate central bone regulatory elements and validate the HPD sheep model for dental research.