Introduction: The objective of this study was to monitor the effects of chemomechanical preparation (CMP) performed with 6% sodium hypochlorite and calcium hydroxide-based intracanal medication (ICM) on the levels and diversity of bacteria, endotoxins (lipopolysaccharides [LPS]), and lipoteichoic acid (LTA) in root canals of teeth with symptomatic irreversible pulpitis.
Methods: Samples were collected from 10 teeth with symptomatic irreversible pulpitis before CMP (S1), after CMP (S2), and after ICM (S3). The levels of bacteria, LPS, and LTA were assessed by using checkerboard DNA-DNA hybridization, LAL Pyrogent 5000, and enzyme-linked immunosorbent assay, respectively.