What is the best treatment for a 2 mm fenestration in the lower anterior mandible (tooth #24) located just below the attached gingiva in a patient with a thin gingival biotype, 4 mm vertical bone loss due to bruxism, no endodontic involvement, and excellent oral hygiene?

Treatment Recommendation for Mandibular Fenestration

For this 2 mm fenestration below tooth #24 with excellent oral hygiene and no endodontic involvement, the optimal treatment is guided bone regeneration (GBR) combined with a connective tissue graft, using L-PRF membranes to enhance outcomes and reduce postoperative morbidity.

Rationale and Treatment Algorithm

Primary Concern: Address the Bruxism First

Before any regenerative procedure, you must address the bruxism that caused the 4 mm bone loss. The bruxism is the underlying etiology and will compromise any regenerative outcome if left unmanaged 1. Provide an occlusal splint (either conventional or 3D-printed) to distribute occlusal forces and protect the regenerated tissues 2. This is non-negotiable—proceeding without bruxism management will likely result in treatment failure.

Surgical Approach: Combined Regenerative Technique

The fenestration requires a dual approach addressing both the bony defect and the soft tissue coverage:

Step 1: Bone Regeneration Component

• Use guided bone regeneration (GBR) as the foundation, which employs a barrier membrane to exclude non-osteogenic fibroblasts while allowing osteogenic cells to repopulate the defect 3
• Incorporate L-PRF membranes as they provide significant advantages: enhanced bone healing, reduced postoperative pain, and protection in case of wound dehiscence 4
• Create cortical perforations in the fenestration area to ensure adequate blood supply 4
• Fill the defect with chopped L-PRF membrane pieces (preferably the face portion) 4

Step 2: Soft Tissue Coverage

• Given the thin biotype and location just below the attached gingiva, a connective tissue graft is essential for predictable soft tissue coverage 5, 6, 7
• Multiple case reports demonstrate successful fenestration closure using connective tissue grafts with excellent aesthetic outcomes 5, 6, 7
• Cover the regenerated area with L-PRF membranes before placing the connective tissue graft 4

Step 3: Flap Management

• Elevate a split-full-split thickness flap to preserve blood supply 4
• Achieve tension-free primary closure using modified vertical mattress sutures combined with single interrupted sutures (5-0 or 6-0 monofilament non-absorbable) 4
• Make periosteal incisions if necessary to allow coronal advancement without tension 4

Critical Technical Points

Why This Combination Works Best

The thin biotype makes this case particularly challenging—thin tissue is more prone to recession and has limited regenerative capacity. The combination approach addresses multiple problems simultaneously:

• GBR with L-PRF handles the 2 mm bony fenestration and provides scaffolding for bone regeneration
• Connective tissue graft increases tissue thickness and provides robust soft tissue coverage
• L-PRF membranes serve as biological insurance—if wound dehiscence occurs (a real risk with thin biotype), the L-PRF facilitates spontaneous wound closure 4

Common Pitfalls to Avoid

1. Do not attempt soft tissue coverage alone without addressing the underlying bone defect—this will fail given the 4 mm bone loss already present
2. Avoid vertical releasing incisions—use minimally invasive techniques to preserve blood supply 4
3. Do not proceed without bruxism management—the parafunctional forces will destroy your regenerative efforts 1
4. Ensure complete primary closure—any membrane exposure, especially with GBR, can lead to infection and treatment failure 3

Postoperative Protocol

• Soft food diet with no biting/chewing in the treated area for 1 week 4
• No mechanical cleaning of the treated area for 1 week 4
• Chlorhexidine 0.12% rinse twice daily for minimum 3 weeks 4
• Prescribe analgesics 4
• Consider systemic antibiotics given the bone graft material 4
• Remove sutures after 10 days 4

Alternative Consideration

If the patient refuses autogenous tissue harvest, dehydrated amnion-chorion membrane (dHACM) with a double pedicle flap is a documented alternative 8, though the evidence is less robust than for connective tissue grafting. However, given the thin biotype and significant bone loss, the connective tissue graft provides more predictable tissue thickening.

The key to success is the interdisciplinary approach: control the bruxism, regenerate the bone, augment the soft tissue thickness, and achieve tension-free primary closure 7. This patient's excellent oral hygiene is a significant positive prognostic factor that should be leveraged.