The aim of endodontic therapy for an inflamed tooth is to eliminate the source of inflammation. Relieving pain depends on the effectiveness of root canal therapy.3

Postoperative pain in endodontic treatments, affecting 3-58% of patients, is often caused by peri-radicular tissue injuries. Understanding these factors helps professionals select methods and supplies to minimize discomfort.

30 patients will be divided into 3 groups according to the method of activation (10 par ticipants/each). participants will be recruited from the postgrad clinic of the endodontic department faculty of oral and dental medicine, Future University in Egypt Patients with mature mandibular first permanent molar with irreversible pulpitis with apical periodontitis Intervention 1: bio-ceramic sealer activation with Eddy sonic Intervention 2: bio-ceramic sealer activation with AF max Control/Comparator: bio-ceramic sealer without activation The study aims to evaluate the effect of Eddy Sonic and AF max activation of bio-ceramic sealer on postoperative pain in mandibular first molars with symptomatic irreversible pulpitis with apical periodontitis

Inclusion Criteria:

• Age range is from 18 to 40 years old.
• No sex predilection
• Patients seeking root canal treatment.
• restorable teeth.
• Positive patient acceptance for participating in the study.
• patients able to sign informed consent.
• Systematically healthy patient (ASA I, Il).
• Patient who can understand the numerical rate scale and sign an informed consent.
• Mandibular first molar teeth with pain on bite or percussion
• Preoperative sharp (moderate or severe) pain.
• Vital response of pulp tissue to cold pulp tester (ethyl chloride spray).
• widening in periodontal membrane space in radiographic appearance.

Exclusion Criteria:

• Patients with American Association of Anesthesiologists (ASA) classifications other than ASA 1 & Il

• Patients who have already ingested preoperative medication, such as analgesics, non-steroidal, or steroidal anti-inflammatory drugs, within 12 hours of the start of treatment.

• This was done to prevent any misinterpretation of the diagnosis or post-treatment pain severity, as these drugs substantially lower post-endodontic pain (Jorge-Arajo et al.,2018).

• Patients with NSAID allergy.

• Patients having two or more adjacent teeth needing root canal therapy

• Pregnant patients.

• Patients with bleeding disorder.

• Patients with long-term corticosteroid use.

• Teeth having:

  • Necrotic pulp.
  • History or presence of swelling or fistulous tract.
  • Acute/chronic periapical abscess.
  • Mobility more than grade 1.
  • Pocket depth of more than 5mm
  • No possible restorability.
  • Previous root canal treatment.
  • Periapical radiolucency.
  • External or internal resorption
  • Vertical root fracture.

• TMJ problems, bruxism, clenching or traumatic occlusion.

• Inability to understand and perform the given instructions.