GINGIVAL RECESSION - ETIOLOGY, PATHOLOGY, PREVALENCE AND MANAGEMENT

(Postgraduate University Theory Examination - 50 Marks Answer)

I. DEFINITION

1. Gingival recession is defined as the apical migration of the gingival margin below the cemento-enamel junction (CEJ), resulting in exposure of root surface. It represents one of the most common mucogingival conditions encountered in clinical practice (Zucchelli G, Etiology & Prognosis).
2. The term mucogingival surgery was introduced by Friedman (1957) and defined as "surgical procedures designed to preserve gingiva, remove aberrant frenulum or muscle attachments, and increase the depth of the vestibule." In 1993, Miller proposed the broader term periodontal plastic surgery to encompass the correction of ridge form and soft tissue esthetics (Wennström & Zucchelli, Lindhe Clinical Periodontology 6th ed., Chapter 46).

II. CLASSIFICATION

1. Miller's Classification (1985) - the most widely used classification of gingival recession:
   • Class I: Marginal tissue recession that does not extend to the mucogingival junction (MGJ). No bone or soft tissue loss in the interdental area. 100% root coverage predictable.
   • Class II: Marginal tissue recession extending to or beyond the MGJ. No bone or soft tissue loss in the interdental area. 100% root coverage predictable.
   • Class III: Recession extending to or beyond the MGJ with bone or soft tissue loss in the interdental area, or malpositioning of teeth. Only partial root coverage achievable.
   • Class IV: Recession extending beyond the MGJ with severe interdental bone and soft tissue loss or severe tooth malpositioning. Root coverage not predictable (Carranza's Plastic Surgery, Chapter 23).
2. Cairo Classification (2011) - Recession Type (RT):
   • RT1: Recession with no interdental attachment loss
   • RT2: Recession with interdental attachment loss less than or equal to buccal attachment loss
   • RT3: Recession with interdental attachment loss greater than buccal attachment loss (Zucchelli, Etiology & Prognosis).

III. PREVALENCE

1. Gingival recession is one of the most prevalent periodontal conditions. Epidemiological studies show that it affects approximately 50% of the adult population and its prevalence increases with age (Wennström & Zucchelli, Lindhe Chapter 46).
2. Data from the USA National Survey (Löe et al. 1992) found that at least one site of gingival recession was present in 88% of subjects aged 65 years and older and in 50% of subjects aged 18-64 years.
3. Recession is most frequently located on maxillary and mandibular first molars and maxillary canines. The buccal surfaces are most commonly affected.
4. Prevalence increases with age - found more in individuals over 40, with a male predominance. It is also reported that recession with at least 1 mm of root exposure affects 23% of US adults (Wennström & Zucchelli, Lindhe Chapter 46).
5. The mandibular incisors region shows the highest prevalence for trauma-induced recession due to thin underlying bone and prominent root prominences (Zucchelli G, Etiology & Prognosis).

IV. ETIOLOGY

A. Predisposing (Anatomical) Factors

1. Thin buccal bone plate and bone dehiscences/fenestrations: Teeth with thin alveolar bone over buccal root surfaces or dehiscences are at increased risk. When the overlying soft tissue is also thin, even minor trauma can lead to recession (Zucchelli G, Etiology & Prognosis).
2. Thin gingival biotype (thin periodontal phenotype): Wennström (1985) stated that "a thin marginal tissue, in particular in the absence of underlying alveolar bone, will be at greater risk of recession since the plaque-induced inflammatory lesion may occupy and cause destruction of the entire connective tissue portion of the gingiva." Thin tissue offers less resistance to inflammatory or mechanical insults (Cohen, Mucogingival Surgery).
3. Prominent root surfaces / buccally positioned teeth: Teeth positioned labially outside the arch often have no overlying buccal alveolar bone, making them susceptible to recession (Zucchelli G, Etiology & Prognosis).
4. Inadequate width of keratinized gingiva: While Lang and Löe (1972) showed that 1 mm or less may be sufficient for health in good oral hygiene patients, thin or absent attached gingiva is a risk factor when combined with other predisposing factors (Cohen, Mucogingival Surgery).
5. Aberrant frenum and muscle attachments: High frenal pull at the gingival margin can mechanically displace the marginal tissue, prevent proper plaque control, and contribute to recession. Cited by Gottsegen (1954), Corn (1964), and Gorman (1967) as indications for mucogingival surgery (Cohen, Mucogingival Surgery).

B. Initiating / Causative Factors

1. Toothbrush trauma (Brushing-induced recession): The most common cause of isolated recession defects. Incorrect brushing technique (horizontal scrubbing with hard bristles and excessive force) causes traumatic loss of gingival tissue. Diagnosis supported by clean root surface with no surrounding inflammation, which distinguishes it from plaque-related recession (Zucchelli G, Etiology & Prognosis).
2. Plaque-induced recession (Bacterial/inflammatory recession): Subgingival plaque accumulation leads to inflammatory destruction of the marginal soft tissue and underlying alveolar bone. This is characterized by the association with buccal pocketing and may spread to interdental papillae. Unlike brushing-related recession, there is microbial deposit on the root and signs of gingival inflammation (Zucchelli G, Etiology & Prognosis).
   • Mucogingival surgery cannot be performed until adequate plaque control is established and inflammatory signs (bleeding on probing) resolve.
3. Orthodontic tooth movement: Labial movement of teeth can create areas of bone dehiscence, which become the path of least resistance for the onset of recession. If movement continues beyond the labial bone plate, it may actually tear the soft tissues causing a cleft-like lesion. Orthodontic-related recession is often not noted until the retention stage (Zucchelli G, Etiology & Prognosis). Maynard and Ochsenbein (1975) and Coatoam et al. (1981) highlighted this association (Cohen, Mucogingival Surgery).
4. Iatrogenic factors:
   • Subgingival restorations, crown margins placed too deeply
   • Prosthodontic treatment with subgingival preparations (Ericsson & Lindhe 1984)
   • Poorly adapted removable partial dentures (Cohen, Mucogingival Surgery).
5. Trauma from dental floss and foreign objects: Floss-related trauma creates a cleft lesion. The narrow shape of floss clefts makes thorough cleaning impossible, leading to bacterial superinfection. In extreme cases a facial pocket forms growing to the root apex, and late diagnosis follows discovery of an abscess (Zucchelli G, Etiology & Prognosis).
6. Lip and tongue piercings: Lip piercing rubbing against the facial aspect of teeth may cause labial gingival recession. Friction with the interdental gingiva is likely to damage interdental papillae (Zucchelli G, Etiology & Prognosis).
7. Smoking: A major risk factor for periodontal disease generally. Nicotine-induced vasoconstriction masks inflammatory signs. Smoking reduces treatment outcome success rates for root coverage procedures (Carranza's - Preshaw et al., Chapter 23).
8. Periodontal disease: Generalized periodontitis causes both horizontal and vertical bone loss, with clinical recession apparent at facial and interproximal surfaces. When recession is combined with papilla loss and interdental attachment loss, mucogingival surgery cannot successfully cover the lesion (Zucchelli G, Etiology & Prognosis).

V. PATHOLOGY

1. Histopathological features of gingival recession:
   • The junctional epithelium migrates apically as a result of inflammatory tissue destruction. The connective tissue attachment is lost.
   • In plaque-induced recession: Dense polymorphonuclear cell infiltrate, loss of collagen in the lamina propria, destruction of connective tissue attachment apparatus, and loss of alveolar supporting bone (Wennström & Zucchelli, Lindhe Chapter 46).
   • In traumatic recession (brushing/floss): Mechanical abrasion of the surface epithelium, with ulceration and localized connective tissue loss. No underlying periodontal pathology. The root surface is clean and surrounding tissues are free of signs of inflammation (Zucchelli G, Etiology & Prognosis).
2. Tissue barrier concept (Goldman & Cohen 1979): A dense collagenous band of connective tissue retards the spread of inflammation better than loose alveolar mucosa fibers. Increasing the zone of keratinized tissue achieves an adequate tissue barrier (thick tissue), limiting recession as a result of inflammation (Cohen, Mucogingival Surgery).
3. Role of alveolar bone: Baker and Seymour (1976), Lindhe et al. (1973), Rubin (1979), and Lindhe and Nyman (1980) showed that teeth with thin bony support are more susceptible to recession following plaque challenge. Recession is ultimately the clinical manifestation of loss of bone support combined with soft tissue destruction (Cohen, Mucogingival Surgery).

VI. CLASSIFICATION OF SURGICAL PROCEDURES FOR ROOT COVERAGE

1. Root coverage procedures include (Wennström & Zucchelli, Lindhe Chapter 46):
   • Pedicle grafts: rotational flaps (lateral sliding flap, double papilla flap), advanced flaps (coronally advanced flap - CAF, semilunar coronally repositioned flap)
   • Free soft tissue grafts: free gingival graft (FGG), free connective tissue graft (CTG)
   • Bilaminar (combined) techniques: CAF + CTG
   • Regenerative procedures: guided tissue regeneration (GTR), enamel matrix proteins (EMD)
   • Tunnel technique
2. Comparative success rates of root coverage techniques (Zucchelli, Factors Influencing):

VII. MANAGEMENT - CORONALLY ADVANCED FLAP (CAF)

For Single Recession Defects

1. CAF (De Sanctis & Zucchelli 2007; Wennström & Zucchelli 1996): The most widely used pedicle flap technique for root coverage. Since the lining mucosa is elastic, a mucosal flap raised beyond the mucogingival junction can be stretched coronally to cover exposed root surfaces (Lindhe Chapter 46).
2. Surgical technique - CAF for single tooth (Zucchelli CAF):
   • Two oblique releasing incisions are made mesially and distally to the recession defect, diverging apically, creating a trapezoidal flap
   • Coronal portion elevated as a split-thickness flap (surgical papillae are split from the anatomical papillae)
   • Apical portion elevated as a full-thickness flap to the level of the bone crest, then converted to split-thickness to detach periosteal and muscle insertions
   • Root surface is mechanically treated with curettes, then conditioned with 24% EDTA for 2 minutes to eliminate the smear layer and improve fibrin clot adhesion
   • Deepithelialized anatomical papillae act as vascular beds for anchorage of surgical papillae
   • Flap is advanced coronally until the margin lies passively approximately 1 mm coronal to the CEJ
   • Sling sutures anchored around palatal cinguli secure the surgical papillae to their interdental connective tissue beds
3. Predetermining root coverage (Zucchelli): The CEJ point angle (CPA) - the point where the CEJ intersects the facial line angle - is used as the reference for the maximum root coverage (MRC) line. When the facial CEJ cannot be found, the interdental papilla is gently raised to observe the CPA (Zucchelli, Factors Influencing).

VIII. CORONALLY ADVANCED ENVELOPE FLAP FOR MULTIPLE RECESSION DEFECTS

1. Indication: When multiple adjacent teeth are affected by recession, especially with esthetic demands. Zucchelli and De Sanctis (2000) described the CAF for multiple recession defects meeting the following requirements (Zucchelli CAF):
   • Treat recession defects on adjacent teeth in a single surgical procedure
   • Obtain complete root coverage predictably for all defects
   • Use existing gingival tissue near the recession defects
   • Maintain or augment facial keratinized tissue
   • Avoid unesthetic scarring
   • Guarantee good color and thickness match with adjacent soft tissues
   • Be minimally invasive with acceptable postoperative comfort
2. Two variations of CAF for multiple defects (Zucchelli CAF):
   • (i) Lateral approach: Original technique, permits correction of recession defects affecting an entire quadrant (from the central incisor to the mesial root of the first molar). Indicated when the canine has a recession defect > 1 mm in depth.
   • (ii) Frontal approach: Enables simultaneous treatment of recession defects affecting the central and lateral incisors of both sides of an arch. Indicated when recession is absent or < 1 mm at the canine.
3. Suturing in CAF for multiple defects - Lateral approach (Zucchelli CAF):
   • Flap closed with sling sutures anchored around palatal cinguli, with each suture providing anchorage of two surgical papillae
   • Needle enters the most distal surgical papilla from the outside, perforates the epithelialized anatomical papilla, passes to the palatal side, carried mesially, passes facial below the contact point, then returns palatal, completing with a surgical knot
   • For deep and wide recession at central incisors, muscle fiber dissection extends beyond the interincisal midline (interincisal papilla tunneling) to dissect the interincisal frenulum insertions
4. Frontal approach - Maxilla (Zucchelli CAF):
   • Where central incisors have deep and wide recession, muscle fibers from both right and left side flaps should be reflected before suturing
   • Sutures placed alternating from right to left, starting from surgical papilla between second premolar and first molar, proceeding toward the midline
   • This minimizes tension at the two central incisors where greatest flap advancement occurs

IX. BILAMINAR TECHNIQUES

Concept and Indication

1. Bilaminar technique refers to a surgical approach combining a coronally advanced pedicle flap (the outer layer) with a connective tissue graft (CTG) harvested from the palate (the inner layer). The term "bilaminar" reflects the two-layered nature of the reconstruction (Zucchelli, Bilaminar Techniques).
2. The term encompasses several variations (Zucchelli, Bilaminar Techniques):
   • From first to last variation, results become increasingly esthetic and postoperative course less uncomfortable
   • However, increasing difficulty requires greater operator skill
   • In the event of premature cover flap dehiscence, risk of graft necrosis increases progressively
3. Indications for the three main variations (Zucchelli, Bilaminar Techniques):
   • CAF + CTG placed coronal to the CEJ: Indicated for treatment of recession defects in conjunction with prostheses, implants, or discolored roots. To conceal root discoloration, gingival margin thickness must be augmented by placing the graft coronal to the CEJ. However, this increases the risk of cover flap dehiscence and consequent graft exposure.
   • CAF + CTG placed at the CEJ: Indicated for treatment of recession defects lacking apical keratinized tissue and/or those associated with radicular non-carious cervical lesions, buccally dislocated teeth, and/or prominent roots.
   • CAF + CTG placed apical to the CEJ: Indicated for recession defects with apical keratinized tissue that is insufficient (< 1 mm) to provide successful root coverage in a coronally advanced flap.
4. Contraindications for bilaminar techniques (Zucchelli, Bilaminar Techniques):
   • When a pedicle flap is not feasible due to lack of apical keratinized tissue
   • Presence of frenula or muscles inserting marginally
   • White clefts extending into the alveolar mucosa
   • Shallow vestibule, especially in the region of mandibular incisors
5. Surgical technique - Trapezoidal bilaminar technique (Zucchelli, Bilaminar Techniques):
   • Trapezoidal flap design with split-thickness surgical papillae
   • Full-thickness elevation as far as the bone crest
   • Deep split-thickness incision to detach muscle insertions
   • Superficial split-thickness incision
   • Root planing followed by 24% EDTA conditioning for 2 minutes
   • CTG harvested from the palate and positioned at appropriate level (at/coronal/apical to CEJ depending on indication)
   • CAF advanced coronally to cover the CTG

Bilaminar Techniques for Multiple Recession Defects

1. Bilaminar technique for multiple deep recession defects in the mandible (Zucchelli, Bilaminar Techniques):
   • Preferable for treatment of multiple deep recession defects in canine and premolar areas of the mandible
   • Even if a minimum of keratinized tissue remains apical to the root exposure, local muscle tension is likely to cause apical shrinkage of a coronally advanced pedicle flap
   • A two-stage technique is not a good alternative due to patient reluctance and risk from proximity of the mental nerve emergence
   • With bilaminar technique, the CTG is placed only on the root dehiscence - its main purpose is to prevent cover flap shrinkage - and this position does not risk nerve damage
   • By augmenting gingival thickness, the CTG increases root coverage stability over time
   • If any tooth with recession has sufficient remaining keratinized tissue, a CAF alone will suffice
2. Stability of CAF and bilaminar technique (Zucchelli, Bilaminar Techniques):
   • The stability of a coronally advanced flap, whether used alone for root coverage or to cover connective tissue grafts, ensures that there are no esthetic differences between teeth treated with a CAF or a bilaminar technique.

X. FREE CONNECTIVE TISSUE GRAFT (ENVELOPE AND TUNNEL TECHNIQUES)

1. Envelope technique - Indications: Used when the tissue apical to the recession is inadequate for a pedicle graft, or in the mandible where thin mucosa, shallow vestibule, and multiple frenula preclude advanced flap techniques (Wennström & Zucchelli, Lindhe Chapter 46).
2. Envelope technique - Steps (Lindhe Chapter 46):
   1. A split-thickness intrasulcular incision creates a "pocket" (envelope) beneath the marginal mucosa without vertical releasing incisions
   2. The exposed root surface is thoroughly curetted
   3. A free CTG is harvested from the palate and slid into the envelope
   4. Sutures secure the graft; a crossed sling suture advances the mucosal flap coronally
   5. Pressure applied for 5 minutes to closely adapt the graft to the root surface
3. Tunnel technique - For multiple adjacent recessions (Lindhe Chapter 46):
   • Envelopes are prepared for each tooth; lateral split incisions are extended so that multi-envelopes are connected mesially and distally to form a mucosal tunnel
   • Care is taken to avoid detachment of the papillae
   • A single long CTG is positioned inside the tunnel and fixed with interrupted sutures at both extremities
   • Sling sutures advance the mucosal flap coronally over the exposed CTG

XI. MANAGEMENT IN THE MAXILLARY ARCH

1. Selection for maxillary teeth (Wennström & Zucchelli, Lindhe Chapter 46):
   • The CAF is the basic procedure for single as well as multiple recessions in the maxilla
   • If the quality of the mucosa apical to the recession is considered inadequate for root coverage, the procedure is combined with placement of a CTG (bilaminar technique)
   • The frontal or lateral approach is chosen based on the extent and position of recession defects relative to the canine
2. Advantages of CAF in the maxilla:
   • Abundant and thick keratinized tissue available apical to recessions
   • Palatal mucosa provides excellent CTG donor tissue
   • Superior color and texture match between moved tissue and adjacent gingiva
   • No secondary wound at the recipient site (better esthetics vs. free gingival graft)
   • Entire quadrant can be treated in a single procedure (Zucchelli CAF).

XII. MANAGEMENT IN THE MANDIBULAR ARCH

1. Challenges specific to the mandibular arch (Wennström & Zucchelli, Lindhe Chapter 46):
   • Thin mucosa apical to recession
   • Presence of multiple frenula
   • Shallow vestibule - especially in the incisor region
   • Proximity of the mental nerve (risk with free gingival graft apical to bone dehiscence)
   • Strong muscle insertions causing tension on advanced flaps
2. Preferred approach for mandibular recession (Lindhe Chapter 46):
   • Free connective tissue graft with "envelope" or "tunnel" preparation is preferred
   • Avoids the need for vertical releasing incisions and preserves blood supply
   • Protects against muscle pull by placing CTG over the root dehiscence
3. For the mandibular incisor area - bilaminar technique specific note (Zucchelli, Bilaminar Techniques):
   • In the mandibular incisor area it is important to place an external horizontal double mattress suture at the level of the buccal fornix
   • Purpose: to restore the "verticality" of the vestibule and act as a force-breaker by interrupting the muscle tension exerting traction near the gingival margin
   • If the graft needs to be divided for multiple teeth, this should be done after deepithelialization; a larger graft is more stable and easier to deepithelialize

XIII. FACTORS INFLUENCING CHOICE OF SURGICAL TECHNIQUE

1. Factors to consider in technique selection (Zucchelli, Factors Influencing; Wennström & Zucchelli, Lindhe Chapter 46):
   (a) Patient's esthetic requests: Chief complaint is often excessive tooth length. Coverage with tissue whose color and thickness do not match adjacent tissue does not satisfy esthetic demands. Complete root coverage to the CEJ with matching color and thickness is the gold standard.
   (b) Jaw and tooth position: Maxillary teeth are preferentially treated with CAF (± CTG); mandibular teeth with CTG using envelope or tunnel techniques.
   (c) Recession depth and width: Deeper recessions may require bilaminar technique. For shallow recessions with minimal probing depth, the semilunar repositioned flap may suffice.
   (d) Tissue thickness and quality apical to the recession: Thin/inadequate apical tissue necessitates CTG addition (bilaminar technique). Thick, adequate tissue makes CAF alone sufficient.
   (e) Single vs. multiple recession: Single recession - CAF or bilaminar technique for single tooth. Multiple recessions - CAF lateral or frontal approach (Zucchelli & De Sanctis 2000); bilaminar for deep mandibular defects.
   (f) Postoperative instructions: Patient instructed to avoid mechanical tooth cleaning in operated area for 2 weeks, and to rinse twice daily with 0.12% chlorhexidine solution for infection control (Lindhe Chapter 46).

SUMMARY TABLE

KEY REFERENCES (as cited from uploaded files):

• Wennström JL & Zucchelli G. Mucogingival Therapy: Periodontal Plastic Surgery. Chapter 46 in Lindhe - Clinical Periodontology and Implant Dentistry, 6th ed. (2015). Lang & Lindhe (eds). Wiley-Blackwell.
• Zucchelli G. Mucogingival Esthetic Surgery. Multiple chapters: Etiology & Prognosis; CAF for Multiple Recession Defects; Bilaminar Techniques for Single and Multiple Recession Defects; Factors Influencing Choice of Surgical Technique; Post-Operative Management. Quintessence, 2013.
• Zucchelli G & De Sanctis M. (2000). Treatment of multiple recession-type defects in patients with esthetic demands. J Periodontol, 71:506-514.
• Cohen ES. Mucogingival Surgery. In Atlas of Cosmetic and Reconstructive Periodontal Surgery, 3rd ed. BC Decker/PMPH USA.
• Goldman HM & Cohen DW. (1979). Tissue barrier concept. Referenced in Cohen - Mucogingival Surgery.
• Friedman N. (1957). Mucogingival surgery - definition. Referenced in Lindhe Chapter 46.
• Preshaw PM, Chambrone L, Holliday R. Risk Factors of Periodontal Disease (Smoking). Chapter 23 in Carranza's Clinical Periodontology, 13th ed.
• De Sanctis M & Zucchelli G. (2007). CAF for single tooth recession. Referenced in Lindhe Chapter 46.
• Wennström JL (1985, 1987, 1996). Role of attached gingiva and mucogingival surgery. Referenced in Cohen & Lindhe Chapter 46.
• Lang NP & Löe H (1972). Width of keratinized gingiva. Referenced in Cohen - Mucogingival Surgery.

Answer Structure at a Glance