Decision making in periodontal plastic surgery

Gingival biotype: Thin, Medium Thick, Thick

Gingival thickness below 1 mm correlates with a lower likelihood of achieving full root coverage using advanced flaps alone (36). The contour and thickness of the tissue play a crucial role in the outcomes: thicker tissues and abundant residual KT improve the results. Clinicians opt for CAF or sliding flaps when KT is sufficient, or add a graft beneath the flap if the tissue thickness is inadequate to support the flap (37).

Demand for aesthetic patients: High or Low

Aesthetic considerations, particularly in smile design, are increasingly central to dental practice. The key elements influencing smile aesthetics include the facial midline, the smile line, papillary recession, tooth size, shape, position, colour, gingival framework, and lip structure (38–40).

Composition

The hard palate masticatory mucosa (MMhP) consists of three distinct histological layers:

• The epithelial layer,
• The subepithelial connective tissue, including the lamina propria,
• The submucosal layer. The epithelium, which can reach a thickness of 300 micrometers, closely resembles the structure of the gingival epithelium. Under it, the lamina propria is a robust tissue rich in intercellular components, primarily composed of collagen fibrils. This layer is subdivided into a papillary segment and a denser reticular segment, characterized by thick reticular fibers. The submucosa, a connective tissue band, links the lamina propria to the underlying periosteum and contains glands, nerves, and adipose tissue (41). The thickness and makeup of MMhP differ between individuals and anatomical sites. The tuberosity region typically exhibits the highest thickness, exceeding 4 mm, while the palatal mucosa near the second and premolars averages around 3 mm (42).

Anatomical landmarks

The blood supply to the palate originates from the greater palatine artery (GPA), a branch of the maxillary artery, exiting via the greater palatine foramen. The GPA travels along a groove lateral to the greater palatine nerve (GPN), distributing branches to the palatal mucosa and gingiva, and gradually narrows until it connects with the sphenopalatine artery in the incisive canal. Innervation of the palatal gingiva and mucosa is provided by the GPN, which also emerges from the greater palatine foramen and runs medial to the GPA. A palpable crest typically separates these two structures clinically (43).

Donor sites

Preferred sites for autograft harvesting include the anterior and posterior palate, with the latter further divided into tuberosity and lateral regions. Tuberosity grafts tend to be bulkier, while posterior lateral palate grafts are thinner, and anterior palate grafts often provide a larger surface area, which influences their clinical applications. These grafts vary histologically, affecting both volume retention and revascularisation. Clinical observations suggest that the subepithelial connective tissue of the tuberosity and posterior lateral palate is firmer and denser than that of the anterior palate, which may reduce postoperative shrinkage. However, denser grafts may be more prone to necrosis compared to anterior palate grafts. In particular, posterior palate grafts typically require full flap coverage for primary healing, unlike anterior grafts. Consequently, lateral and anterior palate grafts may be better suited for root coverage than tuberosity grafts (44–47).

Four-incision or rectangular graft technique

After assessing the palatal sulcus (in the presence of teeth or implants) and identifying key anatomical features (arteries and nerves), a rectangular outline is created with two parallel mesiodistal incisions and two vertical cuts. The graft is extracted using a blunt tool (including the periosteum) or by partial dissection with a scalpel, resulting in a rectangular free gingival graft (FGG). Outside the mouth, the epithelium is removed with a bi-spray blade to produce an SCTG (52). An alternative approach involves intraoral abrasive de-epithelialization using a high-speed diamond bur, accompanied by ample irrigation, until a bleeding surface appears (56).

Trap Door Technique

This method involves one horizontal incision and two vertical incisions to access the tissue. A partial thickness flap is elevated, approximately 1 mm thick and composed mainly of epithelium and subepithelial connective tissue. The graft can then be harvested in full thickness (with periosteum) or partial thickness (without periosteum), removed, and the site closed by repositioning the pedicle flap (57, 58).

One-incision technique

The aim here is to form a uniform, 1- to 1.5-mm-thick partial-thickness mucosal flap tailored to the recipient site’s needs. A single horizontal incision is made with a bi-styrene blade at a 90-degree angle to the bone. Submining begins from this cut, gradually flattening the angle of the blade with each pass until it aligns nearly parallel to the bone surface. The underlying connective tissue graft (CTG) is isolated by incising the bone on the mesial, distal, and medial sides, then detached from the bone using a periosteal elevator for removal.

Trapezoidal CAF single recession

The procedure begins with the identification of the CEJ and measurement of the distance to the most coronal edge of the recession using a periodontal probe. Coronal flap displacement (CFD) is determined by adding 1 mm to this measurement (CFD = CEJ to coronal GR limit + 1 mm). This value is marked apically from the tips of the mesial and distal papillae (Figure 2a). Then, a 3mm mesiodistal incision is made from the sulcus at these points (Figures 2 b–c). If the tips of the papillae lie on different planes, the incision levels adjust accordingly. At the edges of the horizontal incision, two slightly divergent vertical incisions are made in a coronapical direction, extending 3–5mm past the mucogingival junction (MGJ) to form a trapezoidal flap and define surgical papillae (Figure 2d). The surgeon probes the apical tissues of the GR, deflecting the partial thickness of the surgical papillae to this limit (Figure 2e). The apical KTKT to the GR is elevated full thickness, extending 3 mm beyond the buccal bone crest using a periosteal elevator (Figure 2f). Furthermore, partial-thickness deflection facilitates CFD. Anatomical papillae are deepithelialised with a bifurcated blade or microsurgery scissors (Figure 2g). The flap is sutured coronally with interrupted stitches, beginning at the apical ends of the vertical incisions, first mesioapically, then distoapically, alternately progressing toward the base of the surgical papillae, where a single sling suture secures them (Figure 2h) (56).

Triangular CAF single recession

To determine the initial points for the two oblique incisions, an orthodontic wire is used to measure a curved line running parallel to the cementoenamel junction (CEJ). This line connects the tips of the papillae, with its deepest point at the midpoint, positioned 1 mm coronal to the CEJ. This measurement defines the perimeter of the flap necessary for coronal advancement. The wire is then repositioned to align with the most coronal boundary of the gingival recession (GR), and each half is shaped to follow the gingival margin of the recession. Then, two oblique vertical incisions are made, starting from the end points of the wire and extending parallel to the soft tissue edges of the neighbouring healthy teeth. This ensures that the surgical papillae mirror the shape of the anatomical papillae, with incisions reaching 3 mm beyond the mucogingival junction (MGJ) (Figure 3). The flap is elevated in the same manner as described for the trapezoidal flap technique. In this approach, deepithelialization of the anatomical papillae covers the entire overlapping region, making it more extensive than in other methods. The suturing process follows the same steps as described for the trapezoidal CAF (59).

Envelope CAF (multiple adjacent recessions)

To prevent scarring and enhance blood flow, vertical release incisions are avoided at the mesial and distal sides. Instead, the incisions are expanded to encompass one additional tooth on either side of the treatment area, helping to achieve the intended coronal shift of the flap over the exposed root surfaces. The horizontal incision of the envelope flap comprises oblique submarginal cuts in the interdental spaces, seamlessly transitioning to intrasulcular incisions at the recession sites. Initial cuts are made to the mesial and distal surfaces of the tooth with the most pronounced recession defect (RD). To establish the starting point for these incisions, the recession is measured, and 1 mm is added to this value. This distance is then marked in the sulcular regions of the mesial and distal teeth, beginning at the tips of the respective papillae. The incisions follow an oblique trajectory from the apical peak of the recession on the adjacent teeth to these predetermined points (Figure 4a). For adjacent teeth, a single incision is made on the mesial side for the mesial tooth and the distal side for the distal tooth. This process is repeated, recalculating the origin of the incision based on each tooth recession defect (Figure 4b). The boundaries are established at the central incisors and the first molar, provided that the recession of the mesial root in the latter is less than 1 mm. The oblique submarginal interdental incisions displace each surgical papilla (SP) relative to its anatomical counterpart. The envelope flap is elevated using a split-full-split technique from coronal to apical: the oblique interdental cuts are executed with the blade aligned parallel to the long axis of the tooth, allowing for a split-thickness dissection of the surgical papilla (Figure 4d). The gingival tissue below the exposed roots is lifted as described for single-defect cases (Figure 4e). Lastly, the most apical section of the flap is raised in a split-thickness fashion to support coronal repositioning. The remaining anatomical interdental papilla tissue is removed to form connective tissue beds for suturing the surgical papillae (Figure 4f).

A precise incision will be made in the mucosa of the vestibular lining to relieve muscle tension. It is essential to recognise that achieving proper coronal flap displacement depends on releasing lip and muscle tension in the apical region. Single sling sutures will be used to anchor the buccal flap to exposed root surfaces and to stabilise each surgical papilla on the bed of interdental connective tissue. The buccal flap will eventually be placed 1 mm coronal to the cementoenamel junction (CEJ) (Figure 4g). Furthermore, apically, a horizontal double mattress suture should be applied to minimise lip tension along the marginal edge of the flap (59–60).

CAF + STG

The recipient site is prepared using one of the previously outlined methods, such as triangular or envelope CAF, depending on the chosen flap design. Before repositioning the flap to its intended location, the graft must be fixed in place. The dimensions of the graft should adhere to these specifications:

• a height 1 mm greater than the gingival recession (GR) defect,
• a width 6 mm larger than the mesiodistal recession span at the CEJ,
• A thickness of 1 to 1.5 mm. The graft is attached 1 mm coronal to the CEJ using two interrupted sutures, placed at the surgical papillae bases or to the keratinised tissue (KT) of adjacent healthy teeth, one on the mesial side and one on the distal side. The flap is then sutured back into position following the steps detailed in the earlier CAF techniques.

Tunnel technique (single or multiple recession)

This surgical technique involves placing a soft tissue graft (STG) into a recipient bed configured as a single envelope (for a solitary recession) or multiple envelopes (for adjacent recessions), known as a tunnel. The tunnel consists of a supraperiosteal space beneath a pedicle flap, created without the need for external incisions. The STG is inserted and fixed within this tunnel to cover the exposed roots in the vicinity. A partial thickness sulcular incision is made using a 15c blade along each margin of the gingival recession (GR), aligned parallel to the wall of the buccal bone and extending 1 to 2 mm past the mucogingival junction (MGJ). This incision ensures sufficient relaxation of the pedicle flap to accommodate the STG, which can be either a subepithelial connective tissue graft (SCTG) or a xenogeneic acellular dermal matrix (XADM) within it. The partial dissection extends laterally through the base of the papillae of the affected teeth without completely cutting them. Papillae deflection is prohibited; if it occurs, the procedure must be stopped. The dissection continues 3 to 5 mm mesially and distally toward adjacent healthy teeth to properly position the mesial and distal edges of the STG (Figure 5a). Caution is essential when crossing the MGJ to prevent flap perforation, particularly in the premolar and canine areas of both jaws, where pronounced convexities increase this risk if only a bi-shaft blade is used. A critical aspect is maintaining a single and uniform dissection plane throughout the tunnel. To confirm the smooth passage of the STG, the dissection plane can be inspected using a periodontal probe or an Orban knife (standard or inverted); no resistance, such as frenula, periosteal attachments, or muscle, should be encountered when advancing the probe. Any obstacles must be cleared, typically by applying traction with the probe to release these structures. Two initial sutures are placed using separate needles: one at the most mesial point of the tunnel and another at the most distal (Figure 5b). Each needle passes beneath the partial flap and exits through the most significant or most centrally located recession, where the STG will be inserted. Using these pre-placed sutures, the graft is anchored at its mesial and distal ends with vertical open mattress stitches (Figure 5c). Once secured on both sides, the graft is gently positioned in the tunnel by applying pressure with a blunt instrument while simultaneously pulling the sutures from the mesial and distal ends, allowing it to slide smoothly into place. If the flap is adequately lifted, the STG will rest coronal to the cementoenamel junction (CEJ), and the vertical mesial and distal sutures of the mattress can be tightened and finalised (Figure 5d). A simple square knot, using resorbable sutures, secures the graft in its intended coronal-apical orientation (61–64).