Assessment of Pro-Resolution Mediator Levels in Periodontitis Stage III and IV Before and After Periodontal Therapy

Inclusion Criteria: Inclusion criteria: 1. Adult patients above 18 years old. 2. Interdental CAL at site of greatest loss ≥5 mm or extending to middle third of the root. 3. Interdental CAL at site of greatest loss ≥8 mm or extending to apical third of the root. 4. Probing depth ≥6 mm. 5. Vertical bone loss ≥3 mm. 6. Tooth loss due to periodontitis of ≤4 teeth. (Periodontitis Stage III) 7. Tooth loss due to periodontitis of ≥5 teeth. (Periodontitis Stage IV) 8. Furcation involvement Class II or III Moderate ridge defect. \- Exclusion Criteria: * 1\. Pregnancy or lactation. 2. Smoking more than 20 cigarettes. 3. Immuno-inflammatory conditions of the skin and oral mucosa 4. systemic conditions affecting bone turnover and periodontal health status (e.g. endocrine and connective tissue diseases, bisphosphonate antiresorptive therapy, gastrointestinal diseases related to nutrition and mineral metabolism) 5. Periodontal or orthodontic treatment at least 6 months before the start of the study 6. Use of anti-inflammatory and antimicrobial agents within 3 months before sampling Inclusion criteria for healthy group: 1. Systemically healthy patients. 2. Patients with an age range between 16 to 80 years. 3. Patients have a minimum of 20 teeth. 4. Less than 10% bleeding sites with probing depths ≤3 mm. 5. absence of erythema, oedema.