Stage 3 periodontitis is a condition marked by swift and severe destruction of periodontal tissues. To effectively regenerate osseous defects resulting from periodontal disease, it is crucial to leverage the intrinsic regenerative potential of the periodontium via meticulously formulated therapeutic strategies

The main treatment methods of periodontal diseases involve scaling and root planning (SRP), and periodontal surgery. Periodontopathogens, can penetrate deep by crossing the epithelial barrier which may be difficult to be remove by nonsurgical periodontal therapy (NSPT) alone. A multitude of grafted and non-grafted approaches have been used in the management of Intra-bony defects. However, they do not provide predictable periodontal regeneration.

A systematic review on the use of platelet-rich fibrin (PRF) for managing periodontal defects highlights its promising potential in periodontal regeneration. It forms a fibrin matrix that promotes angiogenesis and enhances healing at defected sites. The review emphasizes PRF's ability to sustain the release of growth factors, which are crucial for osteoblastic proliferation, migration, and adherence. This makes PRF an effective scaffold for cellular elements, facilitating periodontal tissue regeneration.

Laser photobiomodulation (PBM) has emerged as a promising adjunctive treatment as it stimulates cellular processes, enhancing the natural regenerative capabilities of periodontal tissues. Recent studies have demonstrated that PBM, particularly with diode, significantly improves clinical outcomes when combined with conventional periodontal treatments. It promotes osteoblastic proliferation, migration, and adherence, thereby facilitating bone regeneration and reducing periodontal pocket depth. Additionally, PBM enhances angiogenesis and modulates the release of growth factors, creating an optimal healing environment.

Inclusion Criteria:

• Patients with PPD =5 mm and clinical attachment loss of ≥3 mm;
• Presence of 2 walled or 3 walled infra-bony defects posterior segments;
• Evidence of ≥3 mm of intra-bony defect depth evaluated by the visualization of peri-apical radiographs.

Exclusion Criteria:

• Patients requiring antibiotic prophylaxis before the periodontal examination;
• Patients diagnosed with malocclusion at the site of the defect;
• Patients with systemic disease and/or on drugs that contraindicate periodontal surgery;
• Patients with a history of smoking and pan chewing;
• Sites with advanced class II & III furcation involvement.