The term mucogingival surgery was initially introduced in the literature by Friedman38 to describe surgical procedures for the correction of relationships between the gingiva and the oral mucous membrane with reference to three specific problem areas: attached gingiva, shallow vestibules, and a frenum interfering with the marginal gingiva. With the advancement of periodontal surgical techniques, the scope of nonpocket surgical procedures has increased, now encompassing a multitude of areas that were not addressed in the past. Recognizing this, the 1996 World Workshop in Clinical Periodontics renamed mucogingival surgery as “periodontal plastic surgery,”4 a term originally proposed by Miller in 1993 and broadened to include the following areas3,4:
Periodontal plastic surgery is defined as the surgical procedures performed to correct or eliminate anatomic, developmental, or traumatic deformities of the gingiva or alveolar mucosa.3,4 Mucogingival therapy is a broader term that includes nonsurgical procedures such as papilla reconstruction by means of orthodontic or restorative therapy. Periodontal plastic surgery includes only the surgical procedures of mucogingival therapy (see Video 63-1: Periodontal Plastic and Esthetic Surgery).
This chapter discusses the periodontal plastic surgical techniques included in the traditional definition of mucogingival surgery: (1) widening of attached gingiva (2) deepening of shallow vestibules, and (3) resection of the aberrant frena. In addition, esthetic surgical therapy around the natural dentition and tissue engineering (biologic mediator) are included in this chapter. Other aspects of periodontal plastic surgery, such as periodontal-prosthetic surgery, esthetic surgery around implants, and surgical exposure of teeth for orthodontic therapy, are covered in Chapters 51, 66, and 78.
The ultimate goal of mucogingival surgical procedures is the creation or widening of attached gingiva around teeth and implants.4 The width of the attached gingiva varies in different individuals and on different teeth of the same individual (see Chapter 2). Attached gingiva is not synonymous with “keratinized gingiva” because the latter also includes the free gingival margin.
The original rationale for mucogingival surgery was predicated on the assumption that a minimal width of attached gingiva was required to maintain optimal gingival health. However, several studies have challenged the view that a wide, attached gingiva is more protective against the accumulation of plaque than a narrow or a nonexistent zone. No minimum width of attached gingiva has been established as a standard necessary for gingival health. People who practice good, atraumatic oral hygiene may maintain excellent gingival health with almost no attached gingiva.
However, those individuals whose oral hygiene practices are less than optimal can be helped by the presence of keratinized gingiva and vestibular depth. Vestibular depth provides space for easier placement of the toothbrush and prevents brushing on mucosal tissue. To improve esthetics, the objective is the coverage of the denuded root surface. The maxillary anterior area, especially the facial aspect of the canine, often presents extensive gingival recession. In such cases, the covering of the denuded root surface not only widens the zone of attached gingiva but also creates an improved esthetic result. This recession and the resultant denuded root surface have a special esthetic concerns for individuals with a high smile line. A wider zone of attached gingiva is also needed around teeth that serve as abutments for fixed or removable partial dentures, as well as in the ridge areas bearing a denture. Teeth with subgingival restorations and narrow zones of keratinized gingiva have higher gingival inflammation scores than teeth with similar restorations and wide zones of attached gingiva.96,97 Therefore, in such cases, techniques for widening the attached gingiva are considered preprosthetic periodontal surgical procedures. Chapter 66 discusses this subject in detail.
Another objective of periodontal plastic surgery is the creation of vestibular depth when it is lacking. Gingival recession displaces the gingival margin apically, thus reducing vestibular depth, which is measured from the gingival margin to the bottom of the vestibule. As indicated previously, with minimal vestibular depth, proper hygiene procedures are jeopardized. The sulcular brushing technique requires the placement of the toothbrush at the gingival margin, which may not be possible with reduced vestibular depth.
Minimal attached gingiva with adequate vestibular depth may not require surgical correction if proper atraumatic hygiene is practiced with a soft brush. Minimal amounts of keratinized attached gingiva with no vestibular depth benefit from mucogingival correction. Adequate vestibular depth is also necessary for the proper placement of removable prostheses.
Still another important objective of periodontal plastic surgery is to correct frenal or muscle attachments that may extend coronal to the mucogingival junction. If adequate keratinized, attached gingiva is present coronal to the frenum, it may not be necessary to remove the frenum. A frenum that encroaches on the margin of the gingiva may interfere with plaque removal, and the tension on the frenum may tend to open the sulcus. In such cases, surgical removal of the frenum is indicated.
As indicated earlier, the recession of the facial, gingival margin will alter the proper gingival symmetry and result in an esthetic problem. The presence of the interdental papilla is also important to satisfy the esthetic goals of the patient. A missing papilla creates a space that many address as a “black hole.” The regeneration of the lost or reduced papilla is one of the most difficult goals in esthetic periodontal plastic surgery. Another area of concern is the patient who presents an excessive amount of gingiva in the visible area. This condition is often addressed as a “gummy smile” and may be corrected surgically by crown lengthening. The correction of these anatomic defects has become an important part of periodontal plastic surgery.
The future of periodontal plastic surgery will encompass the use of tissue-engineered products at the recipient site to reduce the donor site morbidity. Currently, there are numerous studies, both clinically and in the laboratories, to allow the clinician to use this minimally invasive approach to periodontal plastic surgery.
The most common cause of gingival recession and the loss of attached gingiva is abrasive and traumatic toothbrushing habits. The bone and soft tissue anatomy of the buccal, radicular surface of the dentition is usually thin, especially around the anterior area. Teeth positioned buccally may have an even thinner bone and gingiva. In many instances, such areas may have a complete absence of bone beneath the thin overlying gingival tissue. Such defect in the bone is called a dehiscence. This anatomic status combined with external trauma from overzealous brushing can lead to the loss of gingival tissue. Recession of the gingival tissue and bone exposes the cemental surface of the root, which results in abrasion and “ditching” of the cemental surface apical to the cementoenamel junction (CEJ). The cementum is softer than enamel and will be destroyed before the enamel surface of the crown.
Another cause for gingival recession is periodontal disease and chronic marginal inflammation. The loss of attachment caused by the inflammation is followed by the loss of bone and gingiva. Advanced periodontal involvement in areas of minimal attached gingiva results in the base of the pocket extending close to, or apical to, the mucogingival junction. Periodontal therapy of these areas also results in gingival recession caused by the loss of gingiva and bone.
Frenal and muscle attachments that encroach on the marginal gingiva can distend the gingival sulcus, which creates an environment for plaque accumulation. This condition increases the rate periodontal recession and will contribute to the recurrence of the recession even after treatment (Figure 63-1). These problems are more common on facial surfaces, but may also occur on the lingual surface.11
Abnormal tooth alignment is an important cause of gingival deformities that require corrective surgery and also an important factor in determining the outcome of treatment. The location of the gingival margin, width of the attached gingiva, and alveolar bone height and thickness are all affected by tooth alignment. On teeth that are tilted or rotated labially, the labial bony plate is thinner and located farther apically than on the adjacent teeth; therefore the gingiva is recessed so that the root is exposed.117 On the lingual surface of such teeth, the gingiva is bulbous, and the bone margins are closer to the CEJ. The level of gingival attachment on root surfaces and the width of the attached gingiva after mucogingival surgery are affected as much by tooth alignment as by variations in treatment procedures.
Orthodontic correction is indicated when mucogingival surgery is performed on malposed teeth in an attempt to widen the attached gingiva or to restore the gingiva over denuded roots. If orthodontic treatment is not feasible, the prominent tooth should be reduced to within the borders of the alveolar bone, with special care taken to avoid pulp injury.
Roots covered with thin bony plates present a hazard in mucogingival surgery. Even the most protective type of flap, a partial-thickness flap, creates the risk of bone resorption on the periosteal surface.49 Resorption in amounts that ordinarily are not significant may cause loss of bone height when the bone plate is thin or tapered at the crest.
Normally, the mucogingival line in the incisor and canine areas is located approximately 3 mm apical to the crest of the alveolar bone on the radicular surfaces and 5 mm interdentally.98 In periodontal disease and on malposed disease free teeth, the bone margin is located farther apically and may extend beyond the mucogingival line. The distance between the mucogingival line and the CEJ before and after periodontal surgery is not necessarily constant. After inflammation is eliminated, the tissue tends to contract and draw the mucogingival line in the direction of the crown.31
• Gingival augmentation apical to the area of recession. A graft, either pedicle or free, is placed on a recipient bed apical to the recessed gingival margin. No attempt is made to cover the denuded root surface where there is gingival and bone recession.
• Gingival augmentation coronal to the recession (root coverage). A graft (either pedicle or free) is placed covering the denuded root surface. Both the apical and the coronal widening of attached gingiva enhance oral hygiene procedures, but only the latter can correct an esthetic problem. For preprosthetic purposes, the combination of widening keratinized gingiva apical and coronal to the recession would satisfy this objective. Consideration of the objectives as apical, coronal, or both provides a better understanding of the techniques required to achieve the goals.
Widening of the keratinized attached gingiva (apical or coronal to the area of recession) can be accomplished by numerous techniques, such as the free gingival autograft, free connective tissue autograft, and lateral pedicle flap, which can be used for either objective.
Free gingival grafts are used to create a widened zone of attached gingiva. They were initially described by Bjorn12 in 1963 and have been extensively investigated since that time (Figure 63-3).13
Step 1: Prepare the recipient site. The purpose of this step is to prepare a firm connective tissue bed to receive the graft. The recipient site can be prepared by incising at the existing mucogingival junction with a #15 blade to the desired depth, blending the incision on both ends with the existing mucogingival line. Periosteum should be left covering the bone.
Another technique consists of outlining the recipient site with two vertical incisions from the incised gingival margin into the alveolar mucosa. Extend the incisions to approximately twice the desired width of the attached gingiva, allowing for 50% contraction of the graft when healing is complete. The amount of contraction depends on the extent to which the recipient site penetrates the muscle attachments. The deeper the recipient site, the greater is the tendency for the muscles to elevate the graft and reduce the final width of the attached gingiva. The periosteum along the apical border of the graft is sometimes penetrated in an effort to prevent postoperative narrowing of the attached gingiva.
The #15 blade is used to incise along the gingival margin to separate a flap consisting of epithelium and underlying connective tissue without disturbing the periosteum. Extend the flap to the depth of the vertical incisions. Suture the flap where the apical portion of the free graft will be located. Three to four independent gut sutures are placed. The needle is first passed as a superficial mattress suture perpendicular to the incision and then on the periosteum parallel to the incision (Figure 63-4).
Grafts can also be placed directly on bone tissue. For this technique, the flap should be separated by blunt dissection with a periosteal elevator. The advantages of this variant are less postoperative mobility of the graft, less swelling, better hemostasis,32 and 1.5 to 2 times less shrinkage.52,53 However, there is a healing lag period that is observed for the first 2 weeks.21,22,36
Step 2: Obtain the graft from the donor site. The classic or conventional free gingival graft technique consists of transferring a piece of keratinized gingiva approximately the size of the recipient site. To avoid the large wound that this procedure sometimes leaves in the donor site, some alternative methods have been proposed. The original technique is described first, followed by several of the most common variants.
For the classic technique, a partial-thickness graft is used. The palate is the usual site from which the donor tissue is removed. The graft should consist of epithelium and a thin layer of underlying connective tissue. Place the template over the donor site, and make a shallow incision around it with a #15 blade. Insert the blade to the desired thickness at one edge of the graft. Elevate the edge and hold it with tissue forceps. Continue to separate the graft with the blade, lifting it gently as separation progresses to provide visibility. Placing sutures at the margins of the graft helps control it during separation and transfer and simplifies placement and suturing to the recipient site.10
Proper thickness is important for survival of the graft. It should be thin enough to permit diffusion of fluid from the recipient site, which is essential in the immediate posttransplant period. A graft that is too thin may necrose and expose the recipient site.75,82 If the graft is too thick, its peripheral layer is jeopardized because of the excessive tissue that separates it from new circulation and nutrients. Thick grafts may also create a deeper wound at the donor site, with the possibility of injuring major palatal arteries.112 The ideal thickness of a graft is between 1.0 and 1.5 mm.75,82 After the graft is separated, remove the loose tissue tags from the undersurface. Thin the edge to avoid bulbous marginal and interdental contours. Special precautions must be taken with grafts from the palate.
The submucosa in the posterior region is thick and fatty and should be trimmed so that it will not interfere with vascularization. Grafts tend to reestablish their original epithelial structure, so mucous glands may occur in grafts obtained from the palate.
Step 3: Transfer and immobilize the graft. Remove the sponge from the recipient site; reapply it with pressure if necessary until bleeding is stopped. Remove the excess clot. A thick clot interferes with vascularization of the graft.76
Position the graft and adapt it firmly to the recipient site. A space between the graft and the underlying tissue (dead space) impairs vascularization and jeopardizes the graft. Suture the graft at the lateral borders and to the periosteum to secure it in position. The graft must be immobilized. Any movement interferes with healing. Avoid excessive tension, which can distort the graft from the underlying surface. Every precaution should be taken to avoid trauma to the graft. Tissue forceps should be used delicately and a minimum number of sutures used to avoid unnecessary tissue perforation.
Step 4: Protect the donor site. Cover the donor site with a periodontal pack for 1 week, and repeat if necessary. Retention of the pack on the donor site can be a problem. If facial attached gingiva was used, the pack may be retained by locking it through the interproximal spaces onto the lingual surface. If there are no open interdental spaces, the pack can be covered by a plastic stent wired to the teeth. A modified Hawley retainer is useful to cover the pack on the palate and over edentulous ridges.
The free gingival graft technique is a predictable procedure, but the donor site (palate) is left with an open wound that must heal by secondary intention. The following variant techniques attempt to minimize the donor site wound by removing the donor tissue in a different configuration and altering the shape to maximize coverage over the recipient site. These techniques are (1) the accordion technique, (2) the strip technique, and (3) the combination epithelial-connective tissue strip technique. All are modifications of the free gingival grafts.
The accordion technique, described by Rateitschak et al,88 attains expansion of the graft by alternate incisions in opposite sides of the graft. This technique increases the donor graft tissue by changing the configuration of the tissue.
The strip technique, developed by Han et al,48 consists of obtaining two or three strips of gingival donor tissue about 3 to 5 mm wide and long enough to cover the entire length of the recipient site (Figure 63-5). These strips are placed side by side to form one donor tissue and sutured on the recipient site. The area is then covered with aluminum foil and surgical dressing.
The advantages of this technique are the rapid healing of the donor site. The epithelial migration of the close wound edges (3 to 5 mm) allows rapid epithelialization of the open wound. The donor site usually does not require suturing and heals uneventfully in 1 to 2 weeks.
In some cases, a combination technique can be performed where a deep strip graft is taken from the palate and is split into both an epithelial-connective tissue strip and a pure connective strip. The tissue is obtained as follows: Remove a strip of tissue from the palate about 3 to 4 mm thick, place it between two wet tongue depressors, and split it longitudinally with a sharp #15 blade. Both will be used as free grafts. The superficial portion consists of epithelium and connective tissue, and the deeper portion consists only of connective tissue. These donor tissues are placed on the recipient site as in the strip technique. The minimal donor site wound obtained by two donor tissues from one site is the advantage of this technique.
Another technique to minimize the use of the palate as a donor site is the use of acellular dermal matrix (ADM) as a substitute for palatal donor tissue. The use of the palate as a donor site for gingival augmentation has numerous disadvantages, for not only are the patients fearful of palatal surgery from where the donor tissue is procured but, there is also a limitation on the amount of tissue that can be removed. Currently, there are numerous clinicians who advocate the use of ADM as a substitute for palatal donor tissue. (See Tissue Engineering for more information regarding ADM.) This product is commercially available under the name AlloDerm and is derived from donated human skin.1 Commercial preparation of this tissue includes a multistep proprietary process that removes both the epidermis and the cells that can lead to tissue rejection and graft failure without damaging the matrix. The remaining ADM consists of a nondenatured three-dimensional arrangement of intact collagen fibers, ground substance, and vascular channels.29 Randomized, controlled clinical trials have demonstrated outcomes with ADM equivalent to palatal donor tissue in treatment of gingival recession.1,29,40,79,81,103 Equivalent root coverage has been shown in four trials.1,79,81,103 Equivalent increase in marginal tissue thickness has been demonstrated at 6 and 12 months postoperatively, both by clinical assessment and by histometric analysis.1,29,81 Equivalent attachment to the root surface has been found by histologic evaluation of human block sections at 6 months postoperatively.29
Two surgical techniques are suggested for use of ADM in treating gingival recession. Each is a coronally positioned pouch method. The first is the alternate papilla tunnel (APT) method and the second is the papilla retention pouch (PRP) method (Figure 63-6, A–G).
In the APT method, an incision is made in a papilla adjacent to a tooth with recession while the adjacent papilla is tunneled. The next papilla is incised, and the following papilla tunneled. Intrasulcular incisions are made facial to each tooth and interproximally at each tunneled papilla. The papilla in the anatomic midline is always tunneled to reduce tension and retraction of the recipient pouch. At each incised papilla, a V-incision (or inverted V in the mandibular arch) is made to form a new surgical papilla tip approximately 3 mm from the anatomic papilla tip. The portion of the anatomic papilla coronal to the surgical papilla is denuded to expose a vascular recipient bed for the surgical papilla when coronally advanced. The initial dissection is performed with a microperiosteal elevator, extending apically past the mucogingival junction and laterally under the facial aspect of the tunneled papillae. The tunneling process is facilitated by the access provided at the incised papillae. The tunneled papillae are lifted from the interdental crest by blunt reflection with a curette. Following blunt reflection, supraperiosteal sharp dissection is used to deepen and mobilize the recipient pouch.
On completion of the recipient site preparation, the length of graft needed is measured and trimmed so that the graft will extend 3 mm past the last tooth with recession at each end of the prepared site. The vertical dimension of the graft should be 6 to 8 mm. The rehydrated and trimmed allograft is then placed into the surgical pouch, with the basement membrane surface facing outward, and secured coronally with 6-0 sling sutures. The graft should be well adapted to the root surface, extending to but not coronal to the CEJ and to the apical margin, but not over the papillary recipient beds. The pouch is then coronally advanced to completely cover the allograft and secured with 6-0 or 7-0 sling sutures.
In the PRP method, all papillae are tunneled. Initially, intrasulcular incisions are made facial and proximal to all teeth to be treated plus an additional tooth at each end. Next, full-thickness elevation of the margin is initiated with a microperiosteal elevator extending apically past the mucogingival junction and laterally under the facial aspect of the papillae. The pouch is extended apically and mobilized by supraperiosteal sharp dissection, and the papillae are lifted from the interdental crest as in the APT method. The allograft is rehydrated, measured, and trimmed. Placement of the allograft within the pouch may be accomplished by drawing it in with a suture or placing it through the sulcus with a curette so that it is aligned within the pouch over the exposed roots.
The unique feature of this method is the suturing of the allograft with a subgingival continuous subgingival double-back sling suture. Starting at the anterior end of the graft, the needle of a 6-0 suture is passed from the lingual side through the mesial embrasure and captured on the facial side. The allograft is engaged at the mesial line angle of the tooth, the needle is passed back through the mesial embrasure to the lingual side, around the lingual aspect toward the distal, through the distal embrasure back to the facial and crosses under the papilla to engage the allograft at the mesial line angle of the next tooth. This process continues until the needle has engaged the graft at the mesial line angle of the most distal tooth. At this point, the needle is passed through the mesial embrasure, around the lingual aspect, back to the facial through the distal embrasure, and the graft is engaged at the distal line angle. The needle is then passed back through the distal embrasure, around the lingual aspect, through the mesial embrasure to the facial, and under the papilla to engage the allograft at the distal line angle of the adjacent tooth. This process continues until passing through the distal embrasure of the initial tooth in which the suture is tied with the knot on the lingual side. The entire suture resides subgingivally and draws the graft and the pouch coronally. The PRP procedure is completed by coronally advancing the pouch over the allograft with a series of interrupted 6-0 or 7-0 sling sutures.
Developed over 15 years ago, ADM is a safe and effective biomaterial for use as a substitute for palatal connective tissue in root coverage grafting. There have been no reports of any disease transmission in medical or dental applications over this time period. ADM has proven equivalence to palatal connective tissue for root coverage procedures in randomized controlled clinical trials. It produces a thicker marginal tissue and a higher percentage of root coverage than a coronally advanced flap alone.116 It provides advantages over palatal connective tissue in that it does not require a second surgical site to obtain donor tissue and provides an unlimited amount of tissue to treat multiple teeth in one appointment. The use of AlloDerm under a coronally advanced flap extends the application of the most esthetic procedure in root coverage. Further discussion regarding ADM and other techniques to avoid palatal donor site morbidity involve the use of biologic mediators, which is presented later in this chapter
The success of the graft depends on survival of the connective tissue. Sloughing of the epithelium occurs in most cases, but the extent to which the connective tissue withstands the transfer to the new location determines the fate of the graft. Fibrous organization of the interface between the graft and the recipient bed occurs within 2 to several days.95
The graft is initially maintained by a diffusion of fluid from the host bed, adjacent gingiva, and alveolar mucosa.42 The fluid is a transudate from the host vessels and provides nutrition and hydration essential for the initial survival of the transplanted tissues. During the first day, the connective tissue becomes edematous and disorganized and undergoes degeneration and lysis of some of its elements. As healing progresses, the edema is resolved, and degenerated connective tissue is replaced by new granulation tissue.
Revascularization of the graft starts by the second6 or third44 day. Capillaries from the recipient bed proliferate into the graft to form a network of new capillaries and anastomose with preexisting vessels.54
Many of the graft vessels degenerate and are replaced by new ones, and some of these participate in the new circulation. The central section of the surface is the last to vascularize, but this is complete by the tenth day.
The epithelium undergoes degeneration and sloughing, with complete necrosis occurring in some areas.20,80 It is replaced by new epithelium from the borders of the recipient site. A thin layer of new epithelium is present by the fourth day, with rete pegs developing by the seventh day. Heterotopically placed grafts maintain their structure (keratinized epithelium), even after the grafted epithelium has become necrotic and has been replaced by neighboring areas of nonkeratinized epithelium, which suggests that a genetic predetermination of the specific character of the oral mucosa exists that depends on stimuli originating in the connective tissue.55 This is the basis for the technique that uses grafts composed only of connective tissue obtained from areas in which it is covered by keratinized epithelium.17,30,36
As seen microscopically, healing of a graft of intermediate thickness (0.75 mm) is complete by 10.5 weeks; thicker grafts (1.75 mm) may require 16 weeks or longer.43 The gross appearance of the graft reflects the tissue changes within it. At transplantation, the graft vessels are empty and the graft is pale. The pallor changes to an ischemic grayish white during the first 2 days until vascularization begins and a pink color appears. The plasmatic circulation accumulates and causes softening and swelling of the graft, which are reduced when the edema is removed from the recipient site by the new blood vessels. Loss of epithelium leaves the graft smooth and shiny. New epithelium creates a thin, gray, veil-like surface that develops normal features as the epithelium matures.
Functional integration of the graft occurs by the seventeenth day, but the graft is morphologically distinguishable from the surrounding tissue for months. The graft eventually blends with adjacent tissues, but sometimes, although pink, firm, and healthy, it is somewhat bulbous. This usually presents no problem, but if the graft traps plaque or is esthetically unacceptable, thinning of the graft may be necessary. Thinning the surface of the grafted tissue does reduce the bulbous condition because the surface epithelium tends to proliferate again. The graft should be thinned by making the necessary incisions to elevate it from the periosteum, removing tissue from its undersurface, and suturing it back in place.
Free gingival grafts effectively widen the attached gingiva. Several biometric studies have analyzed the width of the attached gingiva after the placement of a free gingival graft.19,49,52 After 24 weeks, grafts placed on denuded bone shrink 25%, whereas grafts placed on periosteum shrink 50%.62 The greatest amount of shrinkage occurs within the first 6 weeks.
The placement of a gingival graft does not “improve” the status of the gingiva.34,35,108 Therefore the indication for a free gingival graft should be based on the presence of progressive gingival recession and inflammation. When recession continues to progress after a few months with good plaque control, a graft can be placed to prevent further recession and loss of attached gingiva.
Other materials have been used to replace gingival tissue in gingival extension procedures. Attempts with lyophilized dura mater,93 and sclera have not been satisfactory. The use of irradiated free gingival allograft showed satisfactory results,91 but further research is necessary before it can be considered for clinical use.
Free autogenous gingival grafts have been found to be useful for covering nonpathologic dehiscences and fenestrations. Nonpathologic refers to openings of the bone through the tooth surface not previously exposed to the oral environment and found in the course of flap surgery.33
The connective tissue autograft technique was originally described by Edel36 and is based on the fact that the connective tissue carries the genetic message for the overlying epithelium to become keratinized. Therefore only connective tissue from beneath a keratinized zone can be used as a graft (Figure 63-7).
The advantage of this technique is that the donor tissue is obtained from the undersurface of the palatal flap, which is sutured back in primary closure; therefore healing is by first intention. The patient has less discomfort postoperatively at the donor site.
This technique uses the apically positioned flap, either partial thickness or full thickness, to increase the zone of keratinized gingiva. Chapter 59 provides a step-by-step description of the surgical technique for apically displaced flaps, and Figure 63-8 illustrates the procedure.
The apically displaced flap technique increases the width of the keratinized gingiva but cannot predictably deepen the vestibule with attached gingiva. Adequate vestibular depth must be present before the surgery to allow apical positioning of the flap. The edge of the flap may be located in three positions in relation to the bone, as follows:
1. Slightly coronal to the crest of the bone. This location attempts to preserve the attachment of supracrestal fibers; it may also result in thick gingival margins and interdental papillae with deep sulci and may create the risk of recurrent pockets.
3. Two millimeters short of the crest (Figure 63-8, D). This position produces the most desirable gingival contour and the same posttreatment level of gingival attachment as obtained by placing the flap at the crest of the bone.39 New tissue covers the crest of the bone to produce a firm, tapered gingival margin.
Placing the flap short of the crest increases the risk of a slight reduction in bone height,28 but the advantage of a well-formed gingival margin compensates for this.
The “vestibular extension technique,” originally described by Edlan and Mejchar,37 produced statistically significant widening of attached nonkeratinized tissue. This increase in width in the mandibular area reportedly persisted in patients observed for up to 5 years.37,92,110 Currently, this technique is of historic interest only.
The fenestration operation was designed to widen the zone of attached gingiva with a minimum loss of bone height.89,90 It has also been called the periosteal separation technique.26 It uses a partial-thickness flap, except in a rectangular area at the base of the operative field, where the periosteum is removed, exposing the bone. This is the area of fenestration. Its purpose is to create a scar that is firmly bound to the bone.23 It prevents soft tissue separation from the bone and postsurgical narrowing of the attached zone. Results obtained with this technique are not as predictable as with the free gingival graft; therefore it is not widely performed except for small isolated areas.
Understanding the different stages and conditions of gingival recession is necessary for predictable root coverage. Several classifications of denuded roots have been proposed. In the 1960s, Sullivan and Atkins100 classified gingival recession into four anatomic categories: (1) shallow-narrow, (2) shallow-wide, (3) deep-narrow, and (4) deep-wide.