Bacterial Profile Changes During Different Sodium Hypochlorite Irrigation Regimens and Calcium Hydroxide Medicament in Root Canal Treatment

The goal of this clinical trial is to learn how the bacterial profile in infected root canals changes during different phases of routine root canal treatment in adults with chronic apical abscess. The main questions it aims to answer are: * How does the root canal bacterial profile change before and after irrigation with 5.25 percent sodium hypochlorite or 3 percent sodium hypochlorite? * How does the bacterial profile change after calcium hydroxide medicament is placed in the root canal? Participants will: * Receive standard root canal treatment with one of two irrigation regimens (5.25 percent or 3 percent sodium hypochlorite, plus EDTA), * Have root canal samples taken three times (before any treatment, after irrigation, and after calcium hydroxide medicament), and * Have the bacteria in these samples analyzed using 16S rRNA PCR and DNA sequencing.

Inclusion Criteria: * Adult aged between 18 and 75 years. * Physically and mentally able to undergo treatment * Have not used antibiotics within 1 week before treatment. * Permanent molar teeth showing clinical and radiographic signs of chronic apical abscess and considered restorable. * Willing to participate in the study and able to provide written informed consent after receiving an explanation of the study. Exclusion Criteria: * Systemic conditions that require antibiotic prophylaxis for routine dental treatment or other significant systemic disease. * Pregnant or breastfeeding women. * Participants with cognitive impairment. * Teeth with advanced mobility (greater than grade 2). * Teeth with periodontal pockets deeper than 4 mm. * Teeth with radiographic signs of root resorption. * Teeth with calcification or obliteration of the root canal. * Teeth with root fracture or that fracture during treatment. * Teeth with open apices.