The effect of calcium supplement given with a mixture of calcium carbonate and calcium citrate on the mandibular alveolar bone of pubertal rats

To determine whether the mixture of calcium carbonate and calcium citrate, an oral calcium supplement made from sea shell that is called UNICAL, had any beneficial effect on bone debilitation, we examined the mandibular alveolar bone of pubertal Wistar male rats by bone mineral mass, Ca/P ratio microanalysis, and scanning electron microscopy. (1) Bone mineral mass of UNICAL-fed rats in the low-calcium experiment group was not significantly different than the control group, although its value was significantly higher than in pair-fed standard diet rats. However, although the bone mineral mass of UNICAL diet rats in the calcium-deficient experiment group was significantly higher than in pair-fed standard diet rats, it was significantly lower than in the control group. (2) All Ca:P ratio values in experiment groups were significantly lower than that in control group. Ca:P ratio values of UNICAL diet rats were significantly higher than those of pair-fed standard diet rats in experiment groups. Separately, Ca:P ratio was not significantly different between UNICAL diet rats of the calcium-deficient experiment group and standard diet rats of the low-calcium experiment group. (3) On scanning electron microscope observation, UNICAL diet animals were observed to have more sufficient calcareous microdepositions in bone remodeling areas, which was thought to be one of the morphological indications of bone formation, reflecting active calcium utilization in bone metabolism, than pair-fed standard diet animals. These results suggested that the mixture of calcium carbonate and calcium citrate had a positive effect on bone debilitation to a certain extent in growth-period rats.