11.1 Introduction

Gingival recession associated with root exposure affects a large portion of the adult population. It is estimated that more than 50% of the population has one or more teeth with at least 1 mm of recession [1].

Similar prevalence among adults has been reported in other studies. For example, Albandar and Kingman [2] reported the prevalence of 1 mm or more recession in people aged 30 years and older was 58%. Other findings were that gingival recession is more frequently found in men compared to women and recession tends to increase with age.

Gingival recession may be caused by a number of factors. It may be a result of the pathogenesis of periodontal diseases related to inflammation caused by bacteria. Perhaps more commonly, gingival recession is attributed to trauma from aggressive or vigorous use of a toothbrush [3–5]. In fact, gingival recession is found more frequently in people who brush their teeth more frequently and who have good oral hygiene compared to people who have poor oral hygiene [6].

Patient anatomical factors also play a role. For example, crowding or a facial tooth position is often cited as an explanation for root exposure [7]. Tooth morphology itself may even be considered. Long, tapered teeth are more highly associated with root exposure than short, square-shaped teeth. Other findings associated with increased risk of recession include teeth with a thin gingival biotype or underlying bony dehiscences or fenestrations. Occasionally, the buccal-lingual width of a tooth may be wider than its alveolar process [8]. Finally, the presence of a high frenum attachment or frenum pull may place a tooth at higher risk for root exposure [9, 10].

In exploring treatment options to treat or correct gingival recession, two types of flap surgery techniques are primarily used: the coronally advanced flap and the lateral sliding flap. The focus of this chapter will be on the lateral sliding flap as well as its various modifications and advancements.

The lateral sliding flap accomplishes these goals when certain conditions exist [12–14]. Of critical importance is the donor site (the adjacent tooth) which must have an abundance of keratinized and attached gingiva (Fig. 11.1, arrow). It is preferable to not have excessive frenum attachments in the area as flap stability and immobility is important. Shallow vestibular depths offer a larger challenge for this procedure due to excessive flap tension as well as their association with thinner tissue. Other factors that maximize predictability include the position of the exposed root in the arch and the position of the tooth that is serving as the donor site.

11.2 Surgical Technique for the Lateral Sliding Flap [15]

The following is a general description for performing a lateral sliding flap procedure to treat gingival recession on a single tooth. A general description is illustrated in Figs. 11.2 and 11.3.

1. 1.

   First, it is important for the teeth to be clean and the gingival tissues free of inflammation (Fig. 11.1).

    
2. 2.

   Following local anesthesia, prepare the recipient site (the tooth with the exposed root) by making a V-shaped incision and forming a beveled wound edge around the recipient site with a sharp scalpel blade (e.g., #15 or a #15c, Fig. 11.2a).

    
3. 3.

   The incised tissue is then removed, and a smooth root surface is prepared with either hand or rotary instruments. Further preparation of the root can be performed chemically using an agent such as citric acid or EDTA. Please note: the use of etching agents may not be imperative to the success of the surgery [16]. A clean root surface, however, is a necessity.

    
4. 4.

   Next, the donor site is prepared by making a vertical incision next to the recipient site at a distance of approximately 1 1/4 to 1 1/2 times the mesial-distal width of the recipient tooth (Fig. 11.2b). The flap will essentially include two papillae: the papilla of the recipient tooth and the closest papilla of the adjacent tooth (the donor tooth). The important part of this step is that the width of the flap must be sufficient to adequately cover the root dehiscence yet still place the flap margins on bone. It is also helpful if the vertical incision is angled slightly toward the recipient bed.

    
5. 5.

   Once the vertical incision has been made, either a full-thickness or partial-thickness flap may be reflected. A combination of a full- and partial-thickness flap is also an option where the portion of the flap that will be placed over the exposed root is full thickness, but the portion of the flap that still covers the donor tooth is partial thickness. Partial-thickness flaps may protect the donor site from further recession and bone loss, especially in the event of an unforeseen fenestration or dehiscence.

    
6. 6.

   After the flap is reflected, a periosteal releasing incision is made with a scalpel or scissors to adequately mobilize the flap to allow it to be laterally positioned without tension.

    
7. 7.

   The flap is then slid laterally to cover the recipient site and sutured (Fig. 11.2c). The papillae are typically secured with a sling suture to help them properly adapt to their new positions while maintaining adequate flap height to fully cover the root surface (Fig. 11.3b, c). The closure of the remaining incision may be performed with either interrupted or continuous sutures. A common suture size for closure is 5-0. Non-resorbable suture materials are recommended.

    
8. 8.

   Finally, test for proper immobilization of the flap by manually manipulating the labial or buccal mucosa to ensure that the flap does not move.

    
9. 9.

   Apply firm pressure to the flap for several minutes with a moist gauze pack to achieve further hemostasis while also encouraging close adaptation of the flap to the recipient site.

    
10. 10.

    Place a periodontal dressing if desired.

     
11. 11.

    Remove sutures at 14 days. The area should not be probed for 12 weeks. Postoperative visits should be as often as necessary to help maintain the area free from plaque and debris (Fig. 11.3d).

     

11.3 Complications and Treatment Modifications

Two primary concerns are typically expressed with the lateral sliding flap. First of all, flap necrosis is a potential complication due to the procedure typically involving only one tooth. With the flap design involving two vertical incisions over a denuded root surface, maintaining an adequate blood supply to the flap is imperative. Whenever possible, the base of the flap should be wider than the cervical portion. One flap design modification to address this potential issue is to widen the flap to include more than one tooth. In addition, it is important that the flap is mobilized enough with periosteal releasing incisions to ensure that the flap lays passively over the exposed root surface. Proper reapproximation of the wound edges and complete closure with sutures will also aid in the rapid healing of the recipient site (Fig. 11.3b, c).

The second complication associated with the lateral sliding flap procedure is the potential root exposure from gingival recession at the donor tooth. This complication is sometimes unpredictable and unavoidable since information about underlying dehiscences or fenestrations on the donor tooth is not necessarily available prior to elevating the flap. In a classic study that examined the changes that occur at both the donor and recipient teeth, it was discovered that about 1 mm of recession occurred at the donor tooth, which also lost approximately 1.25 mm of keratinized tissue, and the average root coverage was 69% [17]. There have been several changes and additions to the lateral sliding flap procedure to address these adverse events [18].

One way to minimize or even prevent gingival recession from occurring on the donor tooth is by designing the flap to leave approximately 2 mm of marginal gingiva on the facial surface of the donor tooth (Figs. 11.2b, c and 11.3b, c). While it is often debated how much keratinized gingiva is necessary for health, it is generally considered acceptable to leave both the donor and recipient teeth with 2 mm of keratinized gingiva, with 1 mm being attached gingiva [19]. Given this recommendation, an increased amount of keratinized gingiva (4 mm) on the donor tooth is necessary in order to consider a lateral sliding flap. This is important to avoid creating mucogingival deficiencies on the teeth. These criteria may eliminate many potential donor teeth from consideration for this procedure, if the lateral sliding flap is the sole root coverage strategy.

11.4 Soft-Tissue Grafts and the Lateral Sliding Flap

Perhaps the most influential change to the success of the lateral sliding flap is the introduction of the subepithelial connective tissue graft (SECTG) (Fig. 11.4a–i). The SECTG was first described by Langer and Langer in 1985 as a root coverage procedure. Over the years, it has been proven as one of the more reliable techniques for gaining root coverage over recession defects while simultaneously thickening the band of keratinized and attached gingiva [20]. Moreover, the predictable formation of a new gingival attachment (versus a periodontal pocket) to the previously denuded root surface has been well-established [21, 22].