Lateral sliding bridge flap technique along with platelet rich fibrin and guided tissue regeneration for root coverage.

Gingival recession is defined as the apical migration of the gingival margin with exposure of root surfaces. The etiology of the condition is multifactorial. Given the high rate of gingival recession defects among the general population, it is imperative that dental practitioners have an understanding of the etiology, complications and management of the condition. A recent innovation in dentistry is the preparation and use of platelet-rich fibrin (PRF) for recession defects. The article presents a case report, which highlights the use of lateral sliding bridge flap along with PRF in a collagen membrane carrier (guided tissue regeneration) for the treatment of multiple recession defects.

INTRODUCTION

Gingival recession is defined as apical migration of the junctional epitheliun, with exposure of root surfaces.[1] Patients may complain of hypersensitivity of the teeth and poor esthetics, and the area may retain dental plaque, which can later cause root caries. Gingival recession may be localized or generalized and can be associated with one or more tooth surfaces.[1]

Periodontal treatment aims to protect and maintain the patient's oral health over his lifetime for adequate function as well as esthetic appearance. Over the last few decades, many different approaches for the treatment for gingival recession have been reported in the literature without a consistent consensus.[2] The use of free autogenous grafts and pedicle grafts including advanced flaps and rotational flaps have been advocated. Combination grafts with either autogenous grafts or allograft and with guided tissue regeneration (GTR) membranes have been reported for root coverage.[3]

The double lateral sliding bridge flap technique was initially proposed by Marggraf,[4] to cover gingival recession in multiple teeth with or without adequate attached gingiva.

GTR consists of procedures attempting to regenerate lost periodontal structures through differential tissue responses. Barrier techniques, using expanded poly-tetra-fluro-ethylene, polygalactin, polylactic acid and collagen are employed to exclude epithelium and the gingival corium from the root as they interfere with regeneration. According to a hypothesis formulated by Melcher,[5] certain cell populations residing in the periodontium have the potential to create new cementum, alveolar bone, and periodontal ligament, provided they have the opportunity to populate the periodontal wound. The hypothesis was experimentally established and histologically verified by Karring et al.[6] The use of GTR for root coverage has been extensively reported in the literature with considerable success.[7]

A recent innovation is the preparation and use of platelet-rich fibrin (PRF), which is a concentrated suspension of the growth factors found in platelets. The growth factors promote regeneration of tissue.[8] The platelet concentrate contains platelet-derived growth factor and transforming growth factor that modulate and up-regulate one growth factors function in the presence of second or third growth factor.[9] This specific feature influenced the decision to use PRF as the test material of choice in this case report. In the case described in this article, platelet rich derivative (PRF membrane) was combined with the double lateral sliding bridge flap technique for root coverage of multiple teeth. A collagen membrane (HEALIGUIDE®) was used as a carrier material.

CASE REPORT

A 38-year-old male patient reported to the Department of Periodontology with the chief complaint of hypersensitivity in lower front tooth region for 4 months. Clinical examination revealed Miller's Class III recession in mandibular anterior teeth measuring 2 mm each in mandibular central incisors, 1 mm in left lateral incisor, 3 mm in right lateral incisor and 4 mm each in mandibular canines [Figure 1]. The probing depth was recorded as 3 mm around the involved teeth. The medical history of the patient was non-significant.

Figure 1

Pre-operative view

Pre-surgical procedure

The surgical procedure was explained to the patient and informed consent was obtained. Preparation of the patient was carried out, which included scaling and root planning of the entire dentition and oral hygiene instructions. The probing depth was recorded as 2 mm after initial preparation.

Prf preparation

Blood of the patient was drawn in 10 ml test tubes without an anticoagulant and centrifuged immediately. Blood was centrifuged using a table top centrifuge (REMY Laboratories) for 12 min at 2700 rpm.

The resultant product consisted of the following three layers:

The top most layer consisting of acellular platelet poor plasma

PRF clot in the middle

Red blood cells at the bottom [Figure 2].

Figure 2

Preparation of platelet rich fibrin

PRF can be obtained in the form of a membrane by squeezing out the fluids in the fibrin clot [Figure 3].

Figure 3

Platelet rich fibrin membrane

The PRF membrane was placed over GTR membrane (HEALIGUIDE®) [Figure 4].

Figure 4

Placement of platelet-rich fibrin membrane over guided tissue regeneration membrane

Surgical procedure

It included the bridge flap technique given by Marggraf[4] and later modified by Romanos.[10] Under local anesthesia, an arch shaped or semilunar incision was given in the vestibule at a distance, which was twice the amount of gingival recession plus 2 mm (2* gingival recession + 2 mm).[10] This ensures a wide flap, which is necessary for a sufficient blood supply. A split thickness flap was then elevated in the apicocoronal direction [Figure 5] and it was connected with the first incision so that the two flaps communicated with each other. The patency of the reflection was checked with the help of a periosteal elevator or a periodontal probe [Figure 6]. PRF in a collagen membrane carrier was placed over the sites with denuded root surfaces [Figure 7]. The entire flap was then coronally positioned to cover the membrane and sling sutures were placed [Figure 8]. A non-eugenol periodontal dressing (Coe-pack, GC) was given over the surgical site.

Figure 5

Elevation of flap

Figure 6

Patency of flap evaluated

Figure 7

Placement of platelet-rich fibrin membrane using the guided tissue regeneration membrane as carrier

Figure 8

Suturing of flap

Post-surgical care

The patient was prescribed antibiotics (Amoxicillin, 500 mg thrice daily) and analgesics (Ibuprofen, 400 mg thrice daily) for 5 days and 0.12% chlorhexidine digluconate mouth rinse for 4 weeks. The patient was advised to follow routine post-operative periodontal mucogingival instructions, with minor modifications. He was told to avoid pulling on the lips to observe the surgical site. Both the dressing and sutures were removed 10 days after surgery. The patient was recalled after 8 weeks, and the complete root coverage was observed [Figure 9]. Six months follow-up showed stable results [Figure 10]. The patient was satisfied with the treatment.

Figure 9

Post-operative view-8 weeks

Figure 10

Post-operative view-6 months

DISCUSSION

New materials and techniques are being developed these days to predictably satisfy the patient-centered esthetic demands. Root coverage can be performed to alleviate a patient's concerns regarding unsatisfactory esthetics and root hypersensitivity. Gingival recession provides a nidus for microbial plaque and calculus accumulation and can be difficult to maintain with normal oral hygiene measures. In addition, there is the potential for root caries to develop on the denuded root surfaces.[11] Connective tissue grafts (CTGs) are currently considered the gold standard for root coverage since they are highly predictable procedures for treating recession defects.[12] However, a common concern of patients is that CTGs require an additional surgical site and produce added morbidity. Harvesting a palatal or other intraoral donor site causes additional discomfort to the patient and increases chair time for the surgeon.

As per the literature search, this is the first case report where double lateral sliding bridge flap was used along with PRF in a collagen membrane carrier for root coverage of multiple teeth. The use of bridge flap provides a number of advantages. The flap covers the denuded root surface of multiple teeth and is supplied by plasmatic circulation from capillaries in adjacent gingiva, allowing it to survive. In this case, complete root coverage as defined by Miller in 1987[13] was achieved. Miller defined complete root coverage in clinical terms as location of soft-tissue margin at the CEJ, presence of clinical attachment to the root, a sulcus depth of 2 mm or less and absence of bleeding on probing.

The use of platelet concentrate gel in a collagen membrane carrier has been documented to be beneficial.[9] Several studies have established the importance of GTR membrane in treatment of gingival recession. Systematic reviews conducted by Oates et al.[14] and Roccuzzo et al.[15] found that root coverage with GTR membrane showed significant results. A recent innovation in dentistry has been the preparation and use of PRF, a concentrated suspension of the growth factors found in platelets. PRF was first developed by Choukroun et al.[16] Placement of the PRF membrane in recession defects can be used to restore the functional properties of the labial gingiva of the maxillary and mandibular teeth by repairing gingival defects and re-establishing the continuity and integrity of the zone of keratinized gingiva.

Aleksic et al.[1718] concluded that the use of PRF and subepithelial CTG was equally effective in the treatment of gingival recession. They also concluded that the utilization of the PRF resulted in a decreased post-operative discomfort and advanced tissue healing. Jankovic et al.[19] conducted a randomized controlled trial and concluded that the use of PRF membrane in gingival recession treatment provided acceptable clinical results, followed by enhanced wound healing and decreased subjective patient discomfort compared to CTG treated gingival recessions and found no difference between the procedures in gingival recession therapy. Martinez-Zapata et al.[20] conducted a systematic review and concluded that autologous plasma rich in platelets improved gingival recession.

CONCLUSION

Obtaining predictable and esthetic root coverage is the goal of periodontal plastic surgery. Soft-tissue maintenance is the primary line of defense in protecting the tissue from bacterial infection. In this report, double lateral sliding bridge flap along with PRF in a collagen membrane carrier was found to have satisfactory results. It also appears that neither the quantity of gingival recession nor the qualities of the supporting tissues are prerequisites for the success of this technique. The main advantage of this technique is that it is a one-step procedure, which showed complete root coverage as well as increased the zone of keratinized gingiva. The use of PRF and barrier materials in clinical practice has shown beneficial outcomes and holds promise for further procedures in the future.