ANALYSIS OF THE INFECTIOUS/ENDOTOXIC CONTENT OF ROOT CANALS FROM TEETH WITH SYMPTOMATIC AND ASYMPTOMATIC ENDODONTIC INFECTIONS

Abstract

This study aimed to investigate the presence of specific microorganisms in root canals and evaluate the levels of lipopolysaccharide (LPS) and lipoteichoic acid (LTA) in cases of symptomatic necrotic teeth with associated acute apical abscess (AAA – GI) and in asymptomatic necrotic teeth (GII) during endodontic treatment (ET) stages. Microbiological, LPS and LTA samples were collected in different phases of the ET: before chemomechanical preparation (CMP), after CMP, and after intracanal medication (IM), from 20 root canals and from AAA. The effectiveness of decontamination was evaluated by microbial culture. Nested-PCR was performed to investigate specific species of microorganisms. LPS levels were measured by the Limulus Amebocyte Lysate test. ELISA was used to quantify LTA. Data were analyzed by different statistical tests. LPS levels were higher in GI than in GII (p<0.05). In GII, there was a significant reduction in LTA after CMP (p<0.05), whereas in GI the reduction was significant only after IM (p<0.05). In GI, there was an LPS reduction after CMP (p<0.05), whereas in GII the reduction was only significant after IM (p<0.05). Enterococcus faecalis and Fusobacterium nucleatum were frequently detected. LPS levels were higher in symptomatic cases and associated with spontaneous pain. It was concluded that different species can be detected at all stages of the ET. CMP can reduce the microbial load, however not LTA, whose levels remain high even after IM.