This randomized controlled trial aims to compare the effectiveness of calcium hydroxide mixed with 0.2% chlorhexidine digluconate versus calcium hydroxide mixed with saline as intracanal medicaments in reducing postoperative pain in patients with apical periodontitis. A total of 80 adult patients with anterior teeth diagnosed with apical periodontitis will be randomly assigned to two equal groups. After standard chemomechanical root canal preparation, Group A will receive calcium hydroxide with saline, while Group B will receive calcium hydroxide with 0.2% chlorhexidine. Postoperative pain will be assessed using a 10-point Visual Analogue Scale (VAS) at 12, 24, and 48 hours. The primary outcome is the frequency and severity of pain at 24 hours. Data will be analyzed using chi-square or Fisher's exact test, with a significance level of p < 0.05. The study aims to determine whether the addition of chlorhexidine improves the analgesic and antimicrobial effectiveness of calcium hydroxide during root canal treatment.

Inclusion Criteria:

• • Patients age 18 or above 18 year old (to have complete apex formation)

  • Anterior teeth with apical periodontitis (simple root canal morphology)
  • Patients whose medical history does not include a history of certain illnesses, such as HIV, heart disease, or epilepsy (conditions that can affect a patient's rate of healing).

Exclusion Criteria:

• Patient allergic to chlorhexidine digluconate and Calcium hydroxide assessed by history.
• Tooth having necrotic pulp on radiographic examination and electric pulp tester.
• Multiple rooted teeth.
• Previously root canal treated tooth because of procedural errors and periapical infection.