Rubas L. Morphofunctional features of remodeling of tissues of the temporomandibular joint in hyperglycemia

The dissertation is devoted to the study of morphological regularities of remodeling of the structures of the temporomandibular joint in laboratory adult white male rats with experimental hyperglycemia. The peculiarities of remodeling of the structures of the temporomandibular joint in the conditions of experimental diabetes mellitus was studied by a complex of morphological methods. It was established that simulated hyperglycemia in laboratory adult white male rats leads to diabetic arthropathy of the temporomandibular joint. Destructive processes, atrophy of chondrocytes, disturbance of nuclear-cytoplasmic relations, and growth of relative volumes of damaged chondrocytes were observed in the cartilaginous tissues of articular surfaces. Atomic absorption spectral analysis revealed disproportionate, unbalanced changes in the contents of the temporal bone and mandible of macro- and microelements. In two-month arthropathy, the calcium content in the temporal bone decreased by 8.6 % and in the mandible by 11.6 % (p<0.001), phosphorus decreased by 15.4 % and 18.9 % (p<0.001), respectively, the ratio between them changed in the temporal by 8.3 %, and in the lower jaw by 9.1 % (p<0.01) compared with the control. Structural changes were observed in hyperglycemia in the bones, which were characterized by thinning of the trabeculae, hyperplasia of bone marrow cells, a decrease in the number of osteoblasts along the edge of the trabeculae, an increase in osteoclasts in the endosteum, destruction of bone beams and plates, resorption and infiltration. Hyperglycemia led to a pronounced narrowing of the lumens of the microvessels of the afferent and metabolic links of hemomicrocirculatory bed and the expansion of its external part in the masticatory muscles, venous plethora, hypoxia, and damage to endothelial cells, muscle fibers, infiltration and sclerosis.