Relationship Apical Periodontitis and the Main Bacterial Species in the Oral Microbiota

Aim: Apical periodontitis(AP) caused by root canal infection is the most frequent pathological lesion in the jaws. Bacterial products, host immune cells and biologically active factors called locally produced cytokines(such as IL-1, TNF-α) have been reported to play an important role in the pathogenesis of AP. Metalloproteinases(MMP), is a measurable biomarker that plays an important role in the degradation and regeneration of collagen and is an indicator of collagen. This study aimed to determine the main bacterial species in the microbiota as Gr(+) and Gr(-) and to compare the relationship between MMP-9 and TNF-α with controlled patient groups. Methodology:60 patients with AP and extraction indication were included in the study. 30 systemically and orally healthy volunteers were selected as the control group. After access cavity preparation, an initial microbiologic sample(S1) was taken from the root canal. After atraumatic extraction of the tooth, second microbial sample(S2) was taken from the external root surface. After bacterial DNA extraction, 16S rRNA gene primer was designed for sequence analysis. Bacterial community profiling was made by Sanger sequencing of the PCR products. Besides, blood samples were collected from all of the patients. Enzyme-linked immunosorbent assay was used to measure levels of MMP-9 and TNF-α.