Modified single incision technique to harvest subepithelial connective tissue graft.

Dental therapy in general and periodontal therapy in particular is directed increasingly at the esthetic outcome for patients. Gingival recession is one of the most common esthetic concerns associated with periodontal tissues. Although various treatment modalities have been developed, subepithelial connective tissue grafting remains the most successful and predictable technique for treatment of gingival recession. Harvesting a connective tissue graft from the palate is many times not only traumatic, but also very painful for the patient. Use of single incision to harvest the subepithelial connective tissue graft is one of the least traumatic, but relatively difficult technique to accomplish. This article presents a modified single incision technique, which is not only less traumatic and painful, but comparatively simple to employ and master. Two new instruments have been introduced to make harvesting of the connective tissue graft easier.

INTRODUCTION

Reconstructive surgery is performed on abnormal structures of the body caused by congenital defects, developmental abnormalities, trauma, infection, tumors or disease. It is generally performed to improve the function, but may also be performed to approximate a normal appearance.[1]

Periodontal reconstructive surgery consists of a variety of mucogingival procedures including root coverage, crown lengthening, vestibular deepening, papilla reconstruction, and ridge augmentation. Even as the primary objective of these procedures is to benefit periodontal health through the reconstruction of lost hard and soft tissues or by preventing further loss, they also augment the patient's appearance.

As dentistry in general and periodontology in particular are making headway, patients are becoming increasingly aware of periodontal problems. Specifically, gingival recession is becoming a greater concern for patients. The loss of gingival tissue can not only lead to root sensitivity, unnatural restorative contours, cemental erosion, and root caries, but also leads to poor esthetics.

A variety of gingival grafting techniques have been advocated to treat gingival recession, like, lateral pedicle flaps, coronally positioned flaps, free gingival grafts, connective tissue grafts, and guided tissue regeneration, but the subepithelial connective tissue graft (SECTG) technique remains one of the most common and accepted procedure for root coverage. The advent of SECTG, as described by Langer and Langer,[2] predictably increased the root coverage of Miller's Class I and II recession[3] to around 90%.[45] Due to superior esthetics and the consistent results achieved, SECTG has been clearly recognized as a highly effective means of covering recession defects.

Harvesting of SECTG can be done from the palate, maxillary tuberosity or edentulous ridges. The palate remains the most common donor site. The harvesting of SECTGs produces less postoperative morbidity than free gingival grafts. Many modifications of the techniques to harvest SECTGs have been proposed, each subtly different from each other in the number of incisions, flap design, and technique. Edel[6] was first to describe the trap door technique to harvest a SECTG from the palate. Langer and Langer developed the parallel incision method.[2] This technique was modified by Harris,[7] who introduced a scalpel with two blades mounted 1.5 mm apart. Raetzke[8] used two crescent-shaped horizontal incisions that converged in depth to harvest SECTG from the palate.

Bruno[9] advocated another technique, in which two horizontal incisions were used to harvest SECTG.

Hurzeler[10] suggested a single incision technique to harvest SECTG, with advantages of healing, with primary intention at the donor site and very less postoperative morbidity to the patient.

A classification for incision designs, relative to donor site preparation (palate) for subepithelial connective tissue grafting, was proposed by Liu et al.[11] The Liu classification of incision design helps the clinicians to decide about the incisions and also helps to achieve the most effective incision/flap design to harvest the donor tissue.

The purpose of this article is to present a modification of the single incision technique, which makes this technique more easy to use and simple.

SURGICAL TECHNIQUE

Three patients reported with a chief complaint of exposure of root surfaces. All the three patients presented with Kumar and Masamatti's Class I-B (F) recession.[12] The first patient was aware of the mucogingival techniques of grafting and harvesting of the graft from the palate, having undergone free gingival grafting five years back. Clinically and radiographically, there was no interdental soft tissue loss. The patients had no contraindications for surgery and were fit to undergo surgical periodontal treatment.

All the patients were advised subepithelial connective tissue grafting, with a coronally repositioned flap for recession treatment. The surgical treatment modality was explained to them. One factor common between them was the fear of treatment and postoperative pain. The first patient had a very traumatic and painful experience of free gingival grafting five years back and was very apprehensive about the harvesting of the graft from the palate. Taking care of the concerns of all the patients, it was decided that the graft be harvested from the palate using a single incision technique, which was least painful and least traumatic.[101113] The single incision technique was chosen to be implemented, but with modifications of incisions, to improve not only the visibility, but more importantly the ease of taking the graft out through the single incision. After phase I therapy and getting the required blood investigations done, the patients were posted for surgery.

PREPARATION OF THE RECIPIENT SITE

The recipient site was prepared in a similar manner for all the cases. After administering of 2% lignocaine hydrochloride with adrenaline, a local anesthetic, a sulcular incision was made on the labial aspect of the involved tooth. Two vertical incisions were made on the line angles of the adjacent teeth adjoining the recession defect. The vertical incisions were continued beyond the mucogingival junction into the alveolar mucosa. A full-thickness flap was raised till the mucogingival junction, and beyond that a partial thickness flap was raised in the alveolar mucosa. The flap was sufficiently relieved to advance it coronally till the cementoenamel junction. The exposed root was planed. Following this, a template was made using a sterilized aluminum foil and adjusted according to the size of the graft required at the recipient site to cover the recession.

TECHNIQUE TO HARVEST CONNECTIVE TISSUE GRAFT USING THE MODIFIED SINGLE INCISION TECHNIQUE

The template was placed on the palate to mark the extent of the graft, after local anesthesia was administered. A single incision was made just 2 mm apical to the gingival margin [Figure 1]. The blade was placed approximately parallel to the long axis of the palate to give this first incision [Figure 2]. The important point to be noted here was that the first incision was aimed at raising a partial thickness flap [Figure 3] and this incision was dissimilar to the first incision advocated by Hurzeler,[10] who had proposed that the first incision be given at 90 degrees to the long axis of the tooth and directly to the bone. The partial thickness flap was raised as far apically as required, in accordance with the graft size, as measured by the template [Figure 3]. The thickness of the flap was sufficient to reduce the probability of tearing and sloughing.

Figure 1

Single incisions marked on the palate, 2 mm below the gingival margin, extending from the canine to the first molar

Figure 2

(a) Diagrammatic representation of the angulation of the blade to raise a partial thickness flap through the first incision and (b) clinical photograph depicting the positioning of the blade approximately parallel to the long axis of the palate to raise a partial thickness flap

Figure 3

Photographs after raising the partial thickness flaps to the required depth

Following this, the blade was angled perpendicular to the palate through the same incision and continued to the bone [Figure 4]. The order of incisions had been reversed when compared to Hurzeler's single incision technique.[10] After the incision to the bone, the connective tissue was elevated from the underlying bone with a periosteal elevator [Figure 5a]. We could visualize the connective tissue at this stage [Figure 5b–d]. Then two vertical incisions on the mesial and distal ends of the graft and one horizontal medial incision is made (under the partial thickness flap), to release it from the surrounding tissue [Figure 6a and b]. Special blades called the ‘Barraquer cataract knives’ and ‘AVS blade’ were used to make vertical and horizontal incisions [Figure 6c and d].

Figure 4

(a) Diagrammatic representation of the incision by placing the blade perpendicular to the bone surface through the single incision. The black line indicates the thickness of the connective tissue that would be harvested and (b) the clinical photograph depicting the angulation of the blade

Figure 5

(a) Diagrammatic representation of the connective tissue graft elevation and (b-d) The connective tissue grafts held between two instruments can be appreciated in all the three cases

Figure 6

(a) Diagrammatic representation of the mesial and distal vertical incisions and (b) Diagrammatic representation of horizontal medial incision under partial thickness flap to separate graft from surrounding tissue. (c) The new instruments used to make mesial and distal vertical incisions (Barraquer cataract knife) and (d) Horizontal medial incision under partial thickness flap (AVS blade)

The ‘Barraquer cataract knife’ is a part of the ophthalmic armamentarium. [Figures 6c and 7a]. These blades are long, thin, and sharp and extremely useful in making incisions on the mesial and distal ends of the graft. These mesial and distal incisions on the graft are made under the partial thickness flap. As the space under the partial thickness flap is limited, maneuvering of the normal Bard-Parker blade No. 11 or 15 becomes difficult and can lead to tearing of the overlying partial thickness flap. To overcome these difficulties, the ‘Barraquer’ blades were utilized.

Figure 7

Clinical photographs depicting use of the new instruments, to make (a) Mesial and distal vertical incisions and (b) a horizontal medial incision under partial thickness flap

The placement of the medial incision determines the width of the graft. This incision is also made apically under the partial thickness flap and is difficult to visualize [Figure 6b]. An instrument has been envisaged by us, which must have a long thin handle, a terminal shank angled at 100 degrees, with a smooth outer surface, and a cutting edge at the terminal end, perpendicular to the long axis of the instrument. The long thin handle is required to increase the reach of the instrument apically to the depth of partial thickness flap on the palate. The angulation is required for the placement of the incision under the flap, as the medial incision does not have a direct and straight approach. A smooth outer surface of the shank is required so that the instrument does not damage the overlying partial thickness flap. A cutting edge at the terminal end, perpendicular to long axis of the instrument, will make it easy for the operators to make an incision at the medial end of the graft under the flap. Medially the graft was separated using this new instrument [Figures 6d and 7b]. This instrument has been named by us as the ‘AVS blade’ (initial alphabets of names of the first three authors) and is crafted to overcome the difficulties faced by operators in making medial incisions. The graft was harvested through that single incision [Figure 8]. The donor site was sutured using a 3-0 silk suture. Two of the cases have been sutured by circumferential interrupted sutures and one of the cases has been sutured with a suspension suture [Figure 9]. A non-eugenol periodontal pack is placed at the donor site.

Figure 8

Connective tissue graft being harvested through the single incision and the amount of tissue harvested

Figure 9

Donor sites sutured

The harvested subepithelial connective tissue graft was sutured to cover the exposed root surface. The full-partial thickness flap was coronally advanced and sutured to cover the graft completely. Pressure was applied on the graft for five minutes and then a periodontal pack was placed. The patients were prescribed analgesics for three days (ibuprofen 400 mg t.d.s).

The patients were recalled 12 days after the surgery and the sutures were removed. The healing was uneventful. The palatal wounds had healed and completely closed by the twelfth day [Figure 10]. All the three patients were asked to record the pain perception in the palatal area at the time of suture removal, at 12 days, on a visual analog scale (VAS). The VAS scores recorded by three patients were 2, 4, and 3.5, respectively. The mean VAS score was 3.166. Thus, the patients’ reported pain perception on the VAS was mild pain.

Figure 10

The palatal wounds had healed and were completely closed by the twelfth day for all the three patients

DISCUSSION

The single incision technique was advocated in this case to reduce the trauma and pain experienced by patient at the donor site.[1113] The modification to the original technique[10] was done to make the technique simpler and easy to execute. The first incision was aimed at raising a partial thickness flap and this incision was contrary to the first incision advocated by Hurzeler,[10] who had proposed that the first incision be given at 90 degrees to long axis of the tooth, directly to the bone.

The advantage of this modification is that very minimal bleeding is encountered at this initial stage. The thickness of the flap is sufficient to reduce the probability of tearing and sloughing. The reduced bleeding can be attributed to the fact that the partial thickness incision is made superficially and the connective tissue has not been incised through and through to the bone till this stage. The epithelium does not have any blood vessels of its own and so less bleeding is encountered. Less bleeding from the palate at this stage helps in the improvement of visibility. Hurzeler advocated the first incision to the bone.[10] The incision to the bone incises the connective tissue through and through, as also the blood vessels in the connective tissue, causing bleeding and thus reducing visibility.

Below this partial thickness flap, the graft can be visualized and the thickness of the connective tissue gets finalized with the partial thickness incision. The extent of undermining can also be observed accurately. Raising the partial thickness flap first, at this initial stage, results in determining the size of the graft, that is, the length, width, and thickness.

The second incision is continued to the bone. This results in the connective tissue being incised through and through (the order of incisions is reversed in our technique, as compared to Hurzeler's single incision technique).[10] The second incision leads to profuse bleeding, which obscures the visibility at this stage., but by this time the important aspects like the size and thickness of the graft would have been correctly assessed, visualized, and finalized by the clinician.

The advantages of reversing are better visibility, better estimation of the connective tissue graft size, and lastly and most importantly, better control over the incisions, as there are no arbitrary angulations to be followed as mentioned by Hurzeler.[10] The better control of incisions can be justified first by the fact that it is always easier to initially raise a partial thickness on a firm tissue attached to the underlying bone with minimal bleeding. Second, the angulations mentioned by Hurzeler,[10] that is, to turn the blade at 135 degrees after the first incision to the bone, to raise the partial thickness to a separate connective tissue from the overlying epithelium, are very difficult to visualize and follow clinically. Such incisions cannot ensure uniform thickness of the graft. Also it can damage and tear the overlying flap. In Hurzeler's technique, the thickness of the connective tissue obtained will depend on the angulation of the blade after the first incision. Raising a partial thickness flap initially, as advocated by our technique, finalizes the length, width, and thickness of the graft at the initial stage itself.

Two new instruments were used in harvesting the graft. The two vertical incisions and the medial horizontal incision are difficult incisions to execute because of poor visibility. These incisions are very important, as these incisions also play an important role in determining the length and width of the connective tissue to be harvested. As the space to execute these incisions is very less, we had encountered problems in executing these incisions with a No. 11 or No. 15 blade. The use of a No. 11 or a No. 15 blade had resulted in tearing of the overlying partial thickness flap, in a few of our earlier cases. Any injury to the overlying partial thickness flap defeats the whole principle behind a single incision. To overcome the problem, we decided to use two new instruments. The design of these instruments solved the problems we faced when using conventional blades.

Edel's[6] ‘trap-door’ technique, using vertical incisions, is popular, because of the relative ease of obtaining the connective tissue graft. Vertical incisions interrupt the vascular supply to the overlying flap predisposing the palatal flap to sloughing.[61113] The use of two horizontal parallel incisions and wedge techniques, however, avoids the use of vertical incisions, but prevents primary closure of the wound.[7891113] The use of the single-incision technique allows primary closure of the palatal wound. The primary closure of the wound increases patient comfort, hastens the healing, reduces pain, and the chances of complications at the donor site.[101113] The modified technique being a single incision technique also retains the well-documented advantages of the original technique.

The single incision technique, however, might be a little difficult to execute as compared to techniques that use two or three incisions,[1113] but the end results such as faster healing, less trauma, and less pain[101113] make this technique a better option.

CONCLUSION

The modification of the single incision technique offers ease of execution to harvest the graft. It also offers the advantage of less bleeding, better visibility, and early determination of the size of the graft to be harvested. It also retains the advantages offered by the original single incision technique of being less traumatic, faster healing with primary closure, and less postoperative complications.