Evaluation of IL-17, TNF-alpha, RANKL Levels in Gingival Cervicular Fluid of Teeth With Periapical Lesions Diagnosed With Chronic Apical Periodontitis

Inflammatory process begins around root apex as a result of bacterial infection of pulp cavity in chronic apical periodontitis. Bone destruction can begin in apical region after immunological reactions at the end of inflammatory process, and radiolucent periapical lesion seems in this way. If bone destruction around apical region is in the rate of 30%, we can notice this difference eventually. Histological manifestations of periapical inflammation can be observed in the result of pulp necrosis and inflammation around apical region. Mocelular methods can determine the type of therapy in various diseases. Each region and tissue reserve specific host factors. Vast majority of pulpal inflammation was trigerred by microorganisms. Certain bacterial virulence factors may damage host tissue directly, other virulence factors can stimulate prolonged non-specific immune response causing tissue damage. In the last phase of infection, immunopathological destruction of pulp tissue is observed due to humoral response. IL-17 is an important inflammatory cytokine released from T cells of the immune system. TNF-alpha and RANKL are also mediators responsible for bone destruction metabolism. TNF is a cytokine mediating immunologic changes during periodontal disease. TNF induction stimulate secondary mediators taking part as chemotactic cytokines. TNF has two different types; TNF-alpha and TNF-beta. TNF-alpha is a polypeptide cytokine produced by macrophages and monocytes. TNF-alpha stimulates bone resorption . There has been limited researches analyzing GCF, blood and tissue of pulp, dentin-derived fluid and periapical fluid for molecular diagnosis so far. GCF is a fluid derived from gingival groove. This fluid contains a lot of host factors such as anticor, bacterial antigen, protein and cytokines. GCF sampling is a non-invasive method, it can be used to provide diagnostic information in all clinical cases. In this study, we will evaluate the levels of IL-17, TNF-alpha and RANKL in the gingival crevicular fluid of teeth with periapical lesion diagnosed with chronic apical periodontitis. Thus, it will be evaluated whether these markers can be used for diagnosis and follow-up of the disease in teeth with periapical lesions.