Effects of experimental osteoporosis and low calcium intake on postextraction sockets of rats

This study analysed the initial effects of the combination of oestrogen deficiency with a calcium-deficient diet on alveolar bone repair. Sixty-three 3-month-old female rats were either ovariectomized (OVX, n = 42) or sham-operated (SHAM, n = 21). Among the 42 ovariectomized rats, 21 received standard commercial food (OVX) and 21 received food with low calcium content (ESP). The mandibular first molars were extracted bilaterally 15 days after ovariectomy or sham surgery. The rats were weighed and killed at 7, 21 and 45 days after tooth extraction. The results were evaluated by descriptive microscopic analysis, histomorphometry of the trabecular and osteoid volume and mast cell counts. Analysis of the results indicated that trabecular volume and mast cell counts increased significantly over time, while osteoid volume decreased over time. Comparisons between the SHAM and OVX groups demonstrated no statistical differences, while comparison between the OVX and ESP groups indicated differences in trabecular volume and the number of mast cells. The data suggest that hormonal deficiency does not delay alveolar bone repair in OVX rats; however, oestrogen deficiency associated with calcium deficiency can lead to bone resorption through the activation of mast cells.