Effect of Passive Ultrasonic Irrigation on the Reduction of Bacteria and Endotoxins in Root Canals

Clinical Evaluation of the Effect of Passive Ultrasonic Irrigation on the Reduction of Bacteria and Endotoxins in Root Canals

The purpose of this clinical study was to compare the effectiveness of passive ultrasonic irrigation with that of traditional syringe irrigation on the removal of bacteria and endotoxin (lipopolysaccharide [LPS]) from root canals.

Forty teeth with apical periodontitis were randomly allocated into two groups according to the irrigation protocol, passive ultrasonic irrigation (PUI, n = 20) and syringe and needle irrigation (NI, n = 20). Microbiological sampling was performed before (S1) and after the root canal preparation (S2), after the tested irrigation protocols (S3). Total bacteria counts were determined by a quantitative PCR (qPCR) assay; and the endotoxin levels by the LAL assay.

Inclusion Criteria:

• Teeth with necrotic pulps and asymptomatic apical periodontitis

Exclusion Criteria:

• patients who had received antibiotics during the previous 3 months or had any general disease,
• teeth that could not be properly isolated with rubber dam,
• non-restored teeth,
• periodontal pockets depths greater than 4 mm,
• previous endodontic treatment,
• open apex,
• crown/root fracture
• root resorption or calcifications.