This project is a randomized controlled clinical study investigating the effect of Mineral Trioxide Aggregate (MTA) used as an apical plug in root canal obturation on periodontal healing and inflammatory biomarkers in teeth with combined endodontic-periodontal (endo-perio) lesions. The study compares MTA with resin-based sealers and evaluates clinical, radiographic, and biochemical outcomes, including levels of IL-10, TNF-α, and MMP-8 in gingival crevicular fluid. The ultimate goal is to determine which treatment approach improves healing and increases tooth survival in such complex lesions.