2013 年 22 巻 2 号 p. 171-176
Recent research on osteoporosis has led to a number of advances in our understanding of its pathophysiology and treatment. However, much is still unknown, and a consensus is yet to be reached on how osteoporosis affects the jaw. With this in mind, the present study sought to identify changes over time in the mandibular cancellous bone of senile osteoporotic mice by assessing the trabecular structure in their mandible and tibia. The senescence-accelerated mouse strain P6 (SAMP6) (n = 5) was used as the experimental model, whereas the senescence-accelerated mouse strain R1 (SAMR1) served as control (n = 5). All mice were aged 16 weeks. Bone morphometry was performed by taking a series of micro-computed tomography (micro-CT) scans of the same animal at different time points. As a result, the morphometric parameters of bone volume fraction (BV/TV), trabecular thickness (Tb.Th) and trabecular number (Tb.N) in the tibias of the SAMP6 mice were significantly lower than those of the SAMR1 mice. Conversely, there were no consistent differences in these parameters in the jaw bones of SAMP6 or SAMR1 mice. These findings may suggest that relevant load-bearing teeth protect the alveolar bone structure from the degenerative effects of osteoporosis.