The influence of fructose on structural and metabolic features of the tooth-jaw system of rats under conditions of iodine deficiency.

The aim of the study was to investigate an oxidative processes intensity and structural organisation of hard and soft periodontal tissues in rats under conditions of high-fructose diet against the background of iodine deficiency (research group) and standard diet and drinking regime (intact animals). It was found that carbohydrate metabolism was impaired in rats of the research group (glucose content increased by 63.3%, insulin - by 48.2% in blood serum, glycated haemoglobin of whole blood - by 2.1 time, HOMAIR index - by 2.1 times compared to the data in intact rats) and thyroid status (free triiodothyronine and thyroxine content in blood serum decreased by 46.8 and 42.7%, respectively, compared to the control). Under such conditions, the intensity of lipid and protein peroxidation processes in periodontal tissues increases. In particular, the accumulation of diene conjugates and products that react to thiobarbituric acid in the mucous membrane of the alveolar process (by 19.0 and 7.1 times), in the teeth pulp (by 2.2 and 6.3 times) compared to the values in intact animals was found. The activation of peroxidative destruction of proteins is confirmed by an increase in the content of all fractions of their oxidative modification in the studied tissues by 2.8-8.4 times compared to the control values. The results of the histological examination of the alveolar process indicate thinning of the periosteum, disruption of the structural organisation of osteon, reduction in the thickness of bone trabeculae (by 21.8%), optical density of the osteogenic matrix (by 8.9%), area of intertrabecular connective tissue (by 61.0%). Mucosal edema of connective tissue, accumulation of glycosaminoglycans, hypertrophy of all epithelial layers (basal, prickle, keratinized layers - by 25.5-55.9%, granular layer - by 2.3 times), changes of the microcirculatory net were observed in the mucous membrane of the alveolar process. Thus, the combination of high-fructose and iodine-deficient diets causes the development of oxidative stress and destructive changes of the dentoalveolar complex of research animals, which characterises an increase of the risks of dental pathology development. [ABSTRACT FROM AUTHOR]