Evaluation of the infectious/endotoxic content of root canals of teeth with symptomatic/asymptomatic endodontic infections

Abstract

The interior of root canals of teeth with pulp necrosis presents a complex and adequate ecological niche for the development of polymicrobial endodontic infections. The main virulence factor of gram-negative bacteria is lipopolysaccharide (LPS), also known as endotoxins; and in gram-positive bacteria is the lipoteichoic acid (LTA). Root canals with necrotic pulp are considered infectious sites, and may favor diseases such as infective endocarditis in immunocompromised individuals or with cardiac problems. Thus, the present study has as objectives: 1) to investigate the presence of specific microorganisms more detected in the root canals; 2) to detect microorganisms more related to the infective endocarditis; 3) to assess LPS and LTA levels at three specific sites: a) root canals of symptomatic necrotic teeth; B) abscesses associated with symptomatic root canals; C) asymptomatic necrotic root canals during the stages of endodontic treatment (before the chemo-mechanical preparation (CMP), after CMP and after intracanal medication); 4) to correlate the data obtained with the patients' clinical features. Patients who require endodontic intervention presenting necrotic dental pulp with or without painful symptomatology will be selected. Microbiological, LPS and LTA samples will be collected from 20 root canals (10 symptomatic and 10 asymptomatic) and from 10 associated periapical abscesses. Nested-PCR, with specific primers will be used to detect the presence of microorganisms. The quantification of LPS / LTA levels in different stages of the endodontic treatment will be done by ELISA. The data obtained will be tabulated and statistically analyzed, with significance of p <0.05. (AU)