[Study of estrogen deficiency impact on manganese levels in teeth and mandible of rats after ovariectomy].

Deficiency of the estrogens occurring after menopause or ovariectomy leads to osteopenia and osteoporosis. It was confirmed by noninvasion examinations of bones--skeleton, maxilla mandible and teeth. Demineralization of the hard tissues were connected with loss of calcium and phosphorus, however the role of microelements is not completely known (for example role of Mn). The aim of the study was an attempt of explanation of manganese behave in the structure of hard tissues of masticatory system when the level of estrogens was decreased. Experiment was realized on Wistar female rats. They were divided into seven following groups: CL--control, SH--sham operated, OV--after ovariectomy, OVO--ovariectomized which administered "oleum pro injectione", OVH1--OVH3--ovariectomized which administered 17 beta-estradiol in three doses: 1.25 micrograms, 12.5 micrograms, 125.0 micrograms (dose on the rat) twice a week. After ovariectomy the level of manganese in teeth as well as in mandible decreased in compared with control group. Differences were statistically significant. Administration of 17 beta-estradiol of ovariectomized female rats caused increase of manganese content inconsiderable. These results may suggest that ovarian estrogens play an important role in mineralization of bones and teeth and in prophylaxis of postmenopausal osteoporosis.