This study aims to assess Pro-Resolution Mediator levels during non-surgical periodontal therapy in individuals with Stage III and IV periodontitis, comparing them to healthy subjects. Periodontitis, a chronic inflammatory condition affecting tooth-supporting tissues, can lead to tooth loss and systemic complications. Understanding the role of pro-resolving lipid mediators in inflammation resolution may offer insights into therapeutic benefits associated with these mediators.

Periodontitis is a chronic inflammatory disease that affects the tooth-supporting tissues, it produces a slow destruction of the periodontium that may eventually result in tooth loss. Periodontitis is caused by a dysbiosis of the immune system where there is an imbalance between the processes that activate and terminate the inflammatory process.(Van Dyke, 2020) Pro-resolving lipid mediators (PMs) play a key role in actively resolving inflammation, modulating immune responses, and promoting tissue healing. However, the understanding of PMs in periodontitis and their role in the enduring nature of the disease has not been sufficiently studied in a clinical setting. It has been suggested that PM levels vary between periodontitis patients and healthy individual with periodontal therapy potentially restoring the balance between pro- and anti-inflammatory mediators. (Van Dyke, 2017) The study aims to provide insights into inflammation resolution mechanisms in periodontitis and the therapeutic potential of PMs.

This study aims to Assess Pro-Resolution Mediator Levels During Periodontal Therapy in Patients with Periodontitis Stage III and IV compared to healthy patients.

Hypothesis Null Hypothesis: pro-resolution mediators' level before and after non-surgical treatment in stage III and IV periodontitis compared to healthy patients, there will be no difference in level before and after non-surgical treatment between stage III and IV periodontitis compared to healthy patients.

Trial design:

The current study design is a before and after trial with a single (interventional) population measured before and after treatment compared to a negative control of healthy patients.

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.

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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.