Effect of Apical Negative Pressure Irrigation System at Cleaning Lateral Canals and Reduction of Periapical Lesions After Endodontic Therapy

Inclusion Criteria: * Demonstrates understanding of the study and willingness to participate as evidenced by voluntary written informed consent and has received a signed and dated copy of the informed consent form. * Aged at least 18 years. * Understands and is willing, able and likely to comply with all study procedures and restrictions. * Good general and mental health in the opinion of the investigator or medically qualified designee; * No clinically significant and relevant abnormalities of medical history or oral examination; * Absence of any condition that would impact on the subject's safety or wellbeing or affect the individual's ability to understand and follow study procedures and requirements. * Single or multi rooted-canal teeth diagnosed with pulp necrosis and symptomatic/ asymptomatic apical periodontitis as tested with routine diagnostics. * Radiographic evidence of periapical lesion. Exclusion Criteria: * Women who are known to be pregnant or who are intending to become pregnant over the duration of the study. * Women who are breast-feeding. * Pre-existing oral irritations. b) Recent (within 30 days) gingival/oral surgery. c) Any clinically significant or relevant oral abnormality. * Known or suspected intolerance or hypersensitivity to the study materials (or closely related compounds) or any of their stated ingredients. * Any subject requiring re-treatment.