Features of Trace Element Imbalance of Tissues of Tooth-Jaw System under Conditions of Zinc Deficiency Against the Background of Hypothyroid Dysfunction, Insulin Resistance and Obesity of Rats

The relevance of the study is due to the prevalence of periodontal lesions, which may be associated with environmental factors (including deficiency or excess of bioelements in nature), the prevalence of general somatic pathology. Endocrine disorders deserve a special attention due to the constant increase the incidence of diabetes mellitus, obesity, thyroid pathology. The aim of the study – to determine the features of zinc, calcium and magnesium distribution in the cementum of the tooth root, the alveolar process and part, the erythrocytes mass under conditions of zinc and iodine deficiency, high-carbohydrate and high-fat diet. Materials and methods. The study was carried on white outbred mature male rats weighing 150-180 g. Rats of the 1st research group (n=12) received products with a reduced zinc content, 2nd (n=12) – were on an iodine-deficient ration, 3rd (n=12) – were on a high-fructose diet to model insulin resistance, 4th (n=12) – were given a high-fat diet to reproduce obesity. The animals of a control group were on a standard diet and drinking regime of the vivarium. The animals were withdrawn from the experiment after eight weeks of being on the diets. The content of zinc, calcium and magnesium was determined in the cementum of the tooth root, the alveolar process and part, the erythrocyte mass of animals by atomic absorption spectrophotometry after preliminary mineralisation of tissue samples by dry ashing. Thyroid profile and carbohydrate metabolism markers were also determined, and the insulin resistance index was calculated, as well as body mass index. Results. The study found that under conditions of zinc deficiency in the cementum of the tooth root and the alveolar process and part, the zinc content decreases, but the magnesium level increases. Iodine-deficient diet and high-carbohydrate loading causes a decrease of trace elements in the alveolar process and part, a decrease of calcium in the cementum of the tooth root against the background of an increase the level of zinc and magnesium compared to the control. Under the conditions of a high-fat diet, the content of zinc and calcium decreases, but the level of magnesium in the cementum of the tooth root increases. Conclusions. Limited intake of zinc or iodine to organism, excessive carbohydrate or fat loading are the risk factors for trace element imbalance, metabolic disorders, development of endocrine pathology, and significantly increase the risks of periodontal tissue damage.