The goal of this clinical trial is to conduct an in vivo study that allows to compare the periapical healing process of 3 different sealing cements through CBCT, as well as implement the evaluation of these lesions through volumetric measurements to provide high-level scientific information and thus have the possibility of being applied in the clinical dental practice, in patients attending UNICOC dental clinics between 2023 and 2024. The main question it aims to answer is:

• Do bioceramic sealer promote faster periapical healing due to their better sealing capacity and high bio-compatibility?
• Are there no differences between endodontic sealers in terms of apical healing? If there is a comparison group: Researchers will compare Bio-C Sealer (Bioceramic sealer) Zinc-oxide eugenol sealer and AH-Plus epoxy resin sealer to evaluate periapical healing after a six months follow-up of conventional endodontic therapy.

Coronal permanent restoration must be performed no later than 15 days after endodontic therapy.

Inclusion Criteria:

• Patients aged 18 to 60
• Patients systemically healthy (ASA I)
• Patients that require endodontic therapy for single-rooted teeth with pulp necrosis and apical periodontitis (AP).
• CBCT PAI periapical index score 3 or above, with no symptoms at the time of appointment.

Exclusion Criteria:

• Exclusion criteria included other than ASA-1 classification
• Patients with Perforated cortical plates at cbct analysis
• Premature permanent teeth
• Patients with Endodontic-periodontic lesions, dystrophic calcifications, more than 20° root curvature
• Pregnancy or lactation
• Root fracture cases
• Use of analgesics within 12-24 hours root canal therapy and patients with endodontic abscess.