Hanchev K. Pathogenesis periodontal repair mechanisms disorders after the extraction of a tooth in conditions of experimental diabetes mellitus

In scientific work is defined dynamic complex characteristic of the state of the nitrogen monoxide system, of the innate link of the local immunity and of the peculiarities of the regeneration of periodontium soft tissues, were determined the specific features of mandible bone tissue, mineralization of enamel and dentin of molars without extraction of the tooth, and in different periods after its extraction. It was proved that in the mucous membrane of the oral cavity of rats with diabetes mellitus is forming an isoformal imbalance and a high initial level of nitrites, the concentration of which increases after the extraction of the tooth only on the 7th day and remains stable until the 14th day. According to the results of immunohistochemical studies, it was established that for diabetes mellitus is typical widespread macrophage infiltration, because extraction of the tooth slightly increases the expression of CD68, the process is slow, but is characterized by prolongation in the long-term period. The correlation of NOS isoforms in the oral mucosal membrane of rats with experimental diabetes mellitus is characterized by lower initial values of the content and concentration of nNOS and eNOS, but significantly higher iNOS. It was proved that the tooth extraction on the background of experimental diabetes mellitus is characterized by a moderate increase in the expression of eNOS and nNOS from the 1st till the 7th day, but the decrease on the 14th day. High levels of expression of CD68 and Ki-67 proteins that characterize proliferative and reparative relations in the mucous membrane of the rats’ oral cavity, are also typical for diabetes mellitus. It was found that activated macrophages and proliferative active cells are almost absent in the intact periodontium. At experimental diabetes mellitus, on the contrary, is observed a significant diffuse infiltration of the periodontium soft tissue by macrophages and high proliferative activity; on the 1st day after the extraction of the tooth quantitative characteristics of expression of CD68 don’t change, and Ki-67 significantly increase. In accordance with the results of the radiologic study of the semi mandible of the control group of rats, it was determined that the extraction of the tooth of the rats of control groups with normal carbohydrate metabolism parameters is accompanied by dynamic changes in the radiological density not only in the extraction area, the inflammatory process affects the surrounding 2nd and 3rd molars, resulting in its decrease in areas of inter alveolar and inter radicular septums. The further development received the idea regarding the radiological density of tissues of inter alveolar and inter radicular septums, crowns and roots of the first, second and third molars. It was proved that in mandible bone tissue diabetes mellitus favours the strengthening of resorptive processes characterized by low values of radiological density in the area of the root of the 1st molar by 2.27 times, but high in the area of the inter alveolar and inter radicular septums of all three lower molars, at the same time the alveolus healing after the tooth extraction is happening ineffective because of the damage of resorptive and reparative relations.