Abstract: Objective: To compare the changes of alveolar bone and systemic bone mineral density(BMD) of hyperthyrosis rabbits. Methods: Twenty-four New Zealand rabbits were devided into experiment group and control group equally, with half male and half female. Experiment group rabbits were daily injected intraperitoneally with 50 μg/kg levothyrocine diluted by physiological saline solution. Control group rabbits were daily injected intraperitoneally with the same volume physiological saline solution only. FT3, FT4, ALP, Ca, P, Mg, BMD test were given to both groups after 8 weeks. Dual energy X-ray absorptionmetry (DEXA) was used to scan the lumbar vertebra, mandibular, bilateral distal femur for the BMD test. Results: After 8 weeks injection, the difference of FT3, FT4, ALP, Ca, P, Mg, BMD level was significant between experimental group and control group. The numerical changes of FT3, FT4 met the diagnostic criteria for hyperthyrosis, and numerical changes of BMD met the diagnostic criteria for osteoporosis. The BMD of mandibular alveolar bone of hyperthyrosis rabbits was lower than the control group. Conclusion: The BMD of mandibular alveolar bone, lumbar spine and femur in the hyperthyrosis rabbits were lower than the control group. Changes of mandibular alveolar bone density in hyperthyrosis rabbits was in line with the lumbar spine and femur,s.

Key words: Hyperthyrosis , Mandibular alveolar bone, Bone mineral density , Rabbit