CLINICAL. Free gingival grafts to manage recession when and how? Matthew B M Thomas CLINICAL

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1 CLINICAL CLINICAL Free gingival grafts to manage recession when and how? Matthew B M Thomas Gingival recession results from displacement of the gingival margin below the cemento-enamel junction leading to exposure of the root surface of a tooth. Although in many patients recession will go unnoticed and cause no symptoms, a proportion of patients will have problems associated with recession defects. This is particularly the case with isolated and deep defects anteriorly but can also be associated with generalised recession. Although conservative management is the main form of therapy for the problems associated with recession, occasionally deep localised recession may benefit from tissue grafting, of which the free gingival graft is one such technique. The purpose of this article is to summarise briefly the aetiology of gingival recession and describe the role that a free gingival graft may have in the management strategy of carefully selected cases. This will enable dental care professionals to discuss localised recession defect management with their patients. Predisposing factors The predisposing factors for gingival recession are listed in Box 1. Inflammatory periodontal diseases such as aggressive and chronic periodontitis result in gingival inflammation and irreversible attachment and bone loss. Over time, if left untreated, more generalised recession will occur. The aim of periodontal therapy is to reduce this inflammation by disruption of the biofilm. Reduction of inflammation will result in less oedema of the gingival tissues and associated shrinkage will present as gingival recession. It is particularly important that dental professionals warn patients that as a consequence of their successful periodontal treatment there will likely be recession. This will reduce the likelihood of patient distress at any potential aesthetic compromise after treatment. Aggressive tooth brushing techniques, particularly the side to side scrub can propagate recession. This is particularly so for patients with thin gingival tissue, known as a thin biotype. Recession is more likely where there are underlying bony fenestrations or dehiscences. Localised recession, Poor oral hygiene Periodontal disease Following successful periodontal treatment Inappropriate tooth brushing technique Orthodontic treatment Class 2 division 2 malocclusion Iatrogenic Thin gingival biotype Bony fenestrations / dehiscences High fraenal attachment Factitious (self-induced) Trauma Dental restorations Box 1 - Gingival recession Predisposing factors particularly in the mandibular incisor region is often seen following fixed orthodontic therapy. It is theorised that during arch expansion, or proclination of the incisors, the roots are pushed labially through the thin cortical plate. In addition, patients who present with class 2 division 2 malocclusions and an increased traumatic overbite are predisposed to stripping of the labial gingival margins of mandibular incisors. Iatrogenic causes include recession following many kinds of dentoalveolar flap surgery. For example, during dental implant placement if careful flap design, elevation and closure are not performed recession can be seen adjacent to implant sites. More uncommonly, recession can be caused by dental trauma following gingival tears associated with luxation injuries. More disturbingly, it can occur through habitual scratching of the gingival margins, so called factitious injuries, associated with some psychological disorders. It has been recognised for many years that poorly adapted restorations can predispose to recession. In particular, full coverage crowns whose margins are placed subgingivally will become supragingival over time due to gingival recession. 1 In summary, there are several potential 37

2 Figure 1 Type 3 Miller s defect affecting LR2 with inflammation of the gingival margin and a reduction of attached gingivae Figure 2 Recession defects affecting mandibular central incisors with associated plaque deposits aetiologies for gingival recession although in everyday clinical practice most localised recession defects are exacerbated by tooth brushing habits, orthodontics and periodontal treatment. Mechanism of recession formation Regardless of the predisposing factors, the mechanism of formation of an isolated recession defect is believed to be through the fusion of inflamed epithelial down growths, termed rete ridges, that result in a cleft in the gingival margin. Recession is unlikely to occur without pre-existing gingival inflammation; hence the importance oral hygiene instruction has in the management, as outlined later in this article. In addition, high frenulum attachments in areas with a lack of attached mucosa may aggravate the situation. Diagnosis of localised recession Localised recession defects will be identified during a thorough periodontal examination, but more likely following a patient complaint. The patient complaint normally includes tooth sensitivity, pain or bleeding on brushing or concerns regarding the aesthetics of the gingival tissues. Recession defects should be measured with a periodontal probe from the cemento-enamel junction to the depth of the defect and recorded on the periodontal chart. It is also important to consider the width of the recession defect and papilla height as these have been shown to affect the outcome of surgical root coverage procedures. Localised defects have been classified by Miller into 4 types. 2 Type 1 involves recession that extends short of the mucogingival junction. Type 2 extends to or beyond the mucogingival junction. The type 3 defect extends to or beyond the mucogingival junction and also involves loss of soft tissue inteproximally. Finally, type 4 recession defects are associated with significant loss of tissue interproximally that extends to the level of the labial gingival margin. Figure 1 shows a type 3 Miller recession defect with early reduction in height of the interdental papilla. This diagnostic criteria is useful as it is often used to estimate the likely outcome of any surgical intervention. For example, complete root coverage is only possible in Class 1 and Class 2 defects. Consequences of localised recession The patient with a localised recession defect may present with one or more of the following problems 1 Dentine hypersensitivity 2 Bleeding on brushing 3 Discomfort when performing oral hygiene measures 4 Concerns regarding the long term prognosis of the teeth involved 5 Unhappy with appearance Dentine hypersensitivity is obviously a consequence of exposure of root dentine resulting in stimulation of the nerve endings within the pulp via the well-known hydrodynamic theory. In deep recession defects there may be an almost complete loss of keratinised tissue. This means that the marginal tissue will, at least in part, be composed of loose alveolar mucosa. This tissue can prove difficult and painful for the patient to clean and therefore the tissue will become more inflamed, as shown in figure 2, predisposing to further recession. Patients who have noticed the recession defects deepening over a relatively short time need careful assessment as rapidly progressing defects may require surgical intervention sooner. A proportion of patients will also understandably be concerned regarding the appearance of isolated defects. This is more of a concern in the maxilla, in particular in those with high smile lines. Fortunately, defects affecting the mandibular dentition are rarely visible. Overall management strategies As stated in the previous section gingival recession is unlikely to occur in the absence of gingival inflammation. Therefore the initial preventative strategy, once an early recession defect has been identified, is to provide specific oral hygiene instruction. This should include advice on a less aggressive tooth brushing technique using a gentle coronal roll technique with a small headed soft toothbrush. Where there is a degree of crowding a single tufted brush used gently can be particularly useful. Where dentine hypersensitivity is a major symptom then this should be treated using well known strategies that are beyond the scope of this article. Briefly the conservative options include the use of a variety of toothpaste preparations, sealing of the dentinal tubules and advice regarding the avoidance of acidic foods and drink. Generalised recession with loss of interproximal tissue can be improved cosmetically through the provision of a silicone or acrylic removable gingival veneer. Where more conservative methods are considered inappropriate or ineffective for localised recession defects, then surgical management may have a role. It is at this point that referral to a specialist experienced in periodontal surgery may be considered. Over many years several surgical approaches have been used for the management of localised recession defects and more recently biomaterials have been developed that have 38 DENTAL HEALTH

3 Figure 3 Twelve months following the placement of a free gingival graft in the region there is a thicker band of attached keratinized gingivae and improved oral hygiene Figure 4 showing preparation of recipient site apical to recession defect affecting lower left canine removed the necessity for harvesting tissue from the host. Techniques have included the free gingival graft, sub-epithelial connective tissue graft, pedicle grafts, Alloderm, guided tissue regeneration, Emdogain and Mucograft. 3 To discuss all the techniques is outside the scope of this article. The remainder of this article will focus on the description of the free gingival graft which is particularly effective in the treatment of localised recession defects in the mandible that cannot be managed with conservative measures alone. Free gingival graft Indications The free gingival graft can be effective in the management of the problems associated with localised recession. 4,5 Specifically, it is indicated where the recession is in the mandibular dentition or the patient has a low smile. It is particularly useful where there is very limited attached gingivae. The patient should be in good general health and achieving the best oral hygiene possible, but taking account of the difficulties that recession defects can cause. Smoking is known to adversely affect the outcome of all recession coverage procedures and this must be taken into account when planning surgery or avoided altogether. 6 One-stage technique When the patient s only concern is their ability to keep the marginal tissue clean and free of deposits, then attempting root coverage itself may be unnecessary. In addition, generalised recession defects or localised Miller class 3 and 4 defects achieve less predictable root coverage with grafting techniques. Nevertheless, these patients may still benefit from a one stage free gingival graft where the treatment goal is only to increase the thickness of keratinised tissue assisting oral hygiene measures. Figures 1 and 2 show recession defects affecting mandibular incisors which proved impossible for the patient to clean. Surgery was performed to harvest a free gingival graft to augment this tissue. No root coverage procedure was performed. The figures show the reduction in inflammation of the marginal tissue. Following surgery the patient reported less discomfort of the gingival tissue and found the area easier to maintain. (Fig. 3) The one stage free gingival graft technique commences with anaesthesia of both recipient site and the palate, which acts as the donor site. Following thorough cleaning of the root surface, a split thickness flap is prepared at the recipient site to produce a periosteal bed that will provide the blood supply to the graft tissue (Figure 4). An approximately 1.5mm thick gingival graft is dissected from the palate of appropriate dimension to match the recession defect (Figure 5a and b). The graft is then secured to the recipient bed using non resorbable sutures and pressure applied for 5 minutes (Figure 6). Haemostasis is achieved in the palatal site using pressure or chemical Figure 5a and 5b showing harvesting of graft from left side of palate 39

4 CLINICAL cauterisation. A soft vacuum formed surgical stent containing a periodontal dressing is fitted to cover the palatal site and reduce discomfort during the post operative period (Figure 7). The patient should return at 2 weeks for removal of sutures and professional prophylaxis. In the meantime, the patient is given advice regarding analgesia, which will be needed for the first 48 hours particularly for the palatal site. The patient is advised not to use a tooth brush at the operative sites until the review appointment and therefore an antibacterial mouthwash is used during this period. Two-stage technique If root coverage is the goal of treatment then a second surgical procedure is performed to advance the tissue in a coronal direction to cover the recession defect. The following is a description of the second surgical technique. Figure 6 showing securing of graft to recipient site with non resorbable sutures Initial treatment involves the recipient site preparation, harvest of the graft tissue and securing the graft onto the recipient bed, as explained in the previous section. Approximately 8 weeks following the first stage surgery a coronally advanced flap procedure is performed. Figures 8-10 show a coronally advanced flap procedure 8 weeks following harvest of a free gingival graft (different case to one described in figures 4 to 7). During the second stage appropriate local anaesthesia is given and a three sided flap raised with release of the periosteal fibre / sulcus mucosa to allow tension free mobility of the flap. The epithelium over the original papillae is removed to exposed the connective tissue bed. The flap is then advanced in a coronal direction to cover the defect. It is important that the flap is over advanced by 2mm to allow for post operative shrinkage. The flap is secured into its new position using small non resorbable sutures. The sutures are removed after 2 weeks after which the patient can recommence oral hygiene measures. Complications and outcomes As with any surgical procedures patients should be advised to expect some pain, swelling and occasionally bruising following surgery. Occasionally, a graft can be lost during the healing period. Specific problems associated with the free ginigival graft are that there are two surgical sites and that the colour match of the tissue can be poor. The literature suggests that complete root coverage is unpredictable compared to alternatives such as connective tissue grafting, however this technique is particularly effective for increasing the width of keratinized tissue in deep recession cases. 7,8 Figure 7 showing soft surgical stent to protect palate tissues in post-operative period The diagnostic classification described by Miller is particularly useful as it has been used over the years as a prognostic indicator. Complete root coverage is achievable with Class 1 and Class 2 defects as shown in Figures 8 to 10. Complete root coverage is not possible in Miller 3 defects as shown in Figure 11. In addition to preoperative recession depth and width other factors that may have an impact on the outcome of grafting procedures include smoking, post-operative oral hygiene, gingival thickness, papilla height, flap tension and systemic health. 40 DENTAL HEALTH

5 Conclusion Gingival recession will continue to be a presenting complaint in a wide variety of patient populations. The majority of cases can be monitored carefully and patients offered further preventative advice. It is clear that certain recession defects in well motivated patients will benefit from free gingival grafting either to attempt root coverage or merely to increase the thickness of attached gingivae which is easier for the patient to maintain. Dental care professionals should be aware of this treatment option and consider appropriate referrals to a specialist where needed. Figure 11 Only partial root coverage has been achieved in this Miller 3 defect. References 1. Valderhaug J. Periodontal conditions and carious lesions following the insertion of fixed prostheses: a 10 year follow-up study. Int Dent J. 1980; 30(4): Miller PD Jr. A classification of marginal tissue recession. Int J Periodontics Restorative Dent. 1985; 5(2): Pagliaro U, Nieri M, Franceschi D et al. Evidenced based mucoginigval theapy. Part 1: A critical review of the literature on root coverage procedures J Periodontol. 2003; 74(5): Maynard JG Jr. Coronal positioning of a previously placed autogenous gingival graft. J Periodontol. 1977; 48(3): Matter J. Free Ginigival graft for the treatment of gingival recession. A review of some techniques. J Clin Periodiodontol. 1982; 9(2): Souza SL, Macedo GO, Tunes RS. Subepithelial connective tissue graft for root coverage in smokers and non-smokers: A clinical and histologic controlled study in humans. J Periodontol. 2008; 79(6): Bernimoulin JP, Lüscher B, Mühlemann HR et al. Coronally repositioned periodontal flap. Clinical evaluation after one year. J Clin Periodontol. 1975; 2(1): Roccuzzo M, Bunino M, Needleman I and Sanz M. Periodontal plastic surgery for treatment of localized gingival recessions: a systematic review. J Clin Periodontol. 2002; 29(Suppl. 3): About the authors: Matthew is a Clinical Lecturer and Consultant in Restorative Dentistry at Cardiff University Dental Hospital. He qualified from Cardiff Dental School and after he completed his specialist training in Restorative Dentistry and a Master of Philosophy degree in the area of bone regeneration, he worked as Locum Consultant at the Royal London Dental Hospital. He returned to Cardiff in 2012 to take up his current post where his clinical responsibilities include Restorative lead for the Congenital Oral Anomalies MDT which includes the provision of dental implants. He is particularly interested in all surgical aspects of Restorative Dentistry, Endodontics and Periodontics. He trains both undergraduate students and postgraduate students to master s level. Matthew is an examiner for the Royal College of Surgeons in Edinburgh. Address for correspondence: thomasmb@cardiff.ac.uk Figure Coronally advanced flap to cover recession defect associated with the lower right canine 41