You are being asked to participate in this research study because you are being treated at the UCSF Graduate Endodontics department for an endodontic procedure. We are trying to determine the treatment outcomes of one v. two-visit endodontic treatments. .If you decide to continue, we would like to request your consent for a follow up period of 1 year to observe the healing of the abscess. Observation periods occur at 6 months following the completion of the root canal and at 12 months and are a part of the standard of care. We will review findings in the Axium chart, which will be recorded by the treating doctor

This research study includes patients who are receiving endodontic treatment within the UCSF Graduate Endodontics Department. The purpose of the study is to evaluate and compare treatment outcomes between one-visit and two-visit root canal procedures. Participants who choose to continue in the study will be followed for a period of one year so that healing of the periapical abscess can be monitored. Follow-up appointments are scheduled at six months and twelve months after treatment completion, both of which are part of routine standard care. Clinical and radiographic findings documented in the Axium chart by the treating provider will be reviewed as part of the study analysis.

Inclusion Criteria:

• Classified as American Society of Anesthesiologists (ASA) Class I or II
• presenting with radiographic evidence of apical periodontitis-defined as a Cone-Beam Computed Tomography Periapical Index (CBCTPAI) score of 3 or greater according to the Estrela classification

Exclusion Criteria:

• Exclusion criteria included patients with uncontrolled chronic systemic conditions (e.g., diabetes, hypertension, chronic obstructive pulmonary disease), cardiovascular disease, renal or hepatic impairment, and autoimmune disorders
• History of smoking
• Periodontal disease with probing depths ≥ 3 mm.
• Root fractures
• Immature apices
• Resorption
• perforations
• Inability to achieve rubber dam isolation
• Lack of informed consent