Recession & Mucogingival Surgery Notes

Recession & Mucogingival Surgery

Periodontal Plastic Surgery

• Definition: Mucogingival surgery, renamed as periodontal plastic surgery in 1996 by the World Workshop in Periodontics, involves surgical procedures to correct defects in the morphology, position, or amount of gingiva surrounding teeth.
• Coined by: Miller.
• Purpose: To prevent or correct anatomic, developmental, traumatic, or disease-induced defects of the gingiva, alveolar mucosa, or bone.

Treatment Procedures

• Gingival augmentation
• Root coverage
• Correction of mucosal defects at implants
• Crown lengthening
• Gingival preservation at ectopic tooth eruption
• Removal of aberrant labial frenulum
• Prevention of ridge collapse associated with tooth extraction

Role of Attached Gingiva

• Adequate Zone: Critical for health.
• Narrow Zone: Insufficient to protect the periodontium from injury and dissipate pull on the margin.
• Inadequate Attached Gingiva: Facilitates subgingival plaque accumulation, favoring attachment loss and soft tissue recession.
• Gingival Health: Can be maintained regardless of dimensions.

Gingival Recession

• Definition: Location of the gingival margin apical to the cementoenamel junction (CEJ), leading to exposure of the root surface.
• Distinguishing Positions:
  • Actual Position: Coronal end of epithelial attachment on the tooth.
  • Apparent Position: Level of the crest of the gingival margin.
• Severity: Determined by the actual gingival position, not the apparent position.
• Types of Recession (Visibility):
  • Clinically observable recession
  • Hidden recession (covered by gingiva; measured by probing to the epithelial attachment level). Total recession is the sum of both.
• Description: Recession can be described as narrow, wide, shallow, and deep; deep-wide recessions are the most difficult to treat.

Classification of Recession by Cairo et al. (2011)

• RT1: No loss of interproximal attachment.
• RT2: Loss of interproximal attachment less than or equal to buccal attachment loss.
• RT3: Loss of interproximal attachment greater than buccal attachment loss.

Development of Recession

Four distinct stages:

1. Normal or subclinical inflammation
2. Clinical inflammation and proliferation of epithelial rete pegs
3. Increased epithelial proliferation, resulting in loss of the connective tissue core
4. Merging of epithelium, resulting in separation and recession of gingival tissue

Marginal Tissue Recession

• Does not extend to the mucogingival (MG) junction.
• No periodontal loss in the interdental area; 100% root coverage can be anticipated.
• Gingival height is not a critical factor in preventing marginal tissue recession, but recession results in the loss of gingival height.

Factors Affecting Root Coverage

• Patient Specific
  • Smoking
  • Oral hygiene
• Site Specific
  • Depth of defect
  • Presence of frenum
  • Root prominence
  • Root surface caries
  • Non-carious cervical lesion
  • Vestibular depth
  • Gingival biotype
• Technique Specific
  • Flap tension
  • Thickness of tissue flap (>0.8mm)
  • Thickness of graft
  • Position of gingival margin (2.5mm coronal to CEJ)
  • Adjacent IDP
  • Peak Theory (Cohen)

Techniques for Increasing Width of Attached Gingiva

• Gingival augmentation apical to area of recession
• Gingival augmentation coronal to recession (Root coverage)

Criteria for Selecting Techniques for Solving MG Problems

• Surgical site free of inflammation
• Adequate blood supply to donor tissue
• Anatomy of recipient and donor site
• Stability of grafted tissue
• Minimal trauma

Gingival Augmentation Apical to Recession

• Free gingival graft (FGG)
• Free connective tissue autograft
• Apically positioned graft

Free Gingival Autograft

• Uses:
  • To create a widened zone of attached gingiva
  • To deepen the oral vestibule
  • To form new functional attached gingiva
  • For ridge augmentation procedures
  • For pedicle graft where the gingiva of adjacent teeth is insufficient as a donor site
  • Remove frenum and muscle attachment
  • To cover exposed roots

The Classic Technique

Step 1: Prepare Recipient Site

• Prepare periosteal bed; incise at existing MG junction with No. 15 blade; periosteum is left intact.
• Outline recipient site; flap is separated without disturbing the periodontium.
• Suture flap at the apical portion of graft placement using 3-4 independent gut sutures.
• Variant: Grafts can be placed directly on bone. This causes less post-op mobility of graft, less swelling, better haemostasis, 1.5-2 times less shrinkage. A healing lag for the first 2 weeks can be expected.

Step 2: Partial Thickness Graft (epithelium with thin underlying connective tissue) from Palate

• Place template over donor site and make a shallow incision. Insert blade to separate and elevate the edge.
• Sutures on margins of the graft.

Step 3: Transfer and Immobilize Graft

• Remove excess clot. Adapt firmly to the recipient site. Suture graft at lateral orders to the periosteum.

Step 4: Protect Donor Tissue

• This is followed by pack and modified Hawley retainer to cover pack on palate.

Variant Techniques

• Accordion Technique: Alternate incisions on opposite sides of graft are given; expansion of graft occurs.
• Strip Technique: 2 to 3 strips of tissue of 3-5 mm width are taken; placed to form one donor tissue. Rapid wound healing, epithelial migration of close wound edges; rapid epithelialization is seen. Uneventful healing in a week occurs and suturing is not needed.
• Combination Technique: Minimal donor site wound; 3-4 mm thick donor tissue; split longitudinally into epithelial-connective tissue strip and connective tissue strip.

Healing of FGG

• Initial Phase (0 to 3 days): Connective tissue becomes oedematous and disorganized, undergoing degeneration and lysis. Degenerated connective tissue is replaced by granulation tissue.
• Revascularization Phase (2 to 11 days): Anastomoses between blood vessels of recipient bed and graft tissue occur in 4-5 days. A thin layer of new epithelium is present by the fourth day, with rete pegs developing by the seventh day.
• Tissue Maturation (11 to 42 days): Epithelial maturation with the formation of a keratin layer.
• Creeping Attachment: Coronal migration of the soft tissue margin occurs 1 year post-treatment as a result of maturation. It can be used as a secondary mechanism for gaining root coverage.

Gross Appearance of Graft During Healing

• At transplantation, graft vessels are empty, and the graft is pale. Pallor changes to ischemic grayish-white during the first 2 days until vascularization begins, and a pink color appears.

Survival of Graft

• Depends on the diffusion of plasma and subsequent revascularization from those parts of the graft that are resting on the connective tissue bed surrounding dehiscence.
• Other critical factors include preparing a sufficient vascular bed around dehiscence and using a thick graft.

Free Soft Tissue Allograft

• Acellular Dermal Matrix (ADM) meets fundamental biologic requirements for graft material (biocompatibility, physiologic breakdown and removal, immunologically inert).
• Alloderm is composed of proteins, proteoglycans, and there exists the potential for hypersensitive allergic or other immune reactions.
• ADM acts as a biologic regenerative matrix for ingrowth of primordial undifferentiated mesenchymal and endothelial cells.
• No gamma radiation is used, and freeze-drying does not physically damage the collagen bundle or basement membrane complex, leaving them intact.
• Permits normal cell migration, repopulation, incorporation, and maturation.
• No foreign body or giant cell reaction. Turnover by fibroblasts.
• Immunologically inert because it is cell-free.
• Easy to handle, aesthetic, and predictable.
• Complications include infection, resorption of alloderm, and non-integration.

Graft Preparation (Alloderm)

• Rehydrated for a minimum of 10 minutes.
• Improper Rehydration: Cryoprotectants that enable freeze-drying of the dermis without structural damage may be toxic if exposed to cells in high enough concentrations.

Placement of Alloderm

• Assessing