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Comparative clinical evaluation of gingival unit grafts and epithelialized palatal grafts ( free gingival grafts)  in the treatment of gingival recession: A randomised controlled  clinical trial

Introduction:

Gingival recession is one of the most common manifestations of periodontal diseases. The treatment modalities commonly employed to treat gingival recession sites range from free soft tissue autografts , sub epithelial connective tissue grafts, pedicle grafts, soft tissue replacement materials like collagen, alloderm, amniotic membrane etc. Epithelialized palatal grafts (EPG) more popularly known as free gingival grafts are harvested from the palate, at a distance of 2mm from the adjacent gingival margin. EPG though relies on the advantage of tissue transplant from a functionally similar site , has low predictability in its use for root coverage procedure and does not sufficiently replace the esthetics at the recipient area. Gingival unit transfer is an autogenous procedure, used in coverage of denuded roots wherein the graft harvested includes gingival margin along with the keratinised epithelium from the palate, so that the graft morphology and histology resembles the missing structures at the recipient site. The unique and complex vasculature of marginal tissue with its rich anastomosis  improves the chances for graft survival on avascular root surface and increases its predictability for use in root coverage procedures.

Review of literature:

1. Gingival Unit Graft Versus Free Gingival Graft for Treatment of Gingival Recession: A Randomized Controlled Clinical Trial Jenabian et al 2016

In this randomized controlled clinical trial with split mouth design, the authors concluded that gingival unit graft might be an acceptable modality in Miller Class I/II recession defects with advantages over free gingival graft such as significantly superior clinical and esthetic results.

2. Treatment of Localized Gingival Recessions Using Gingival Unit Grafts: A Randomized Controlled Clinical Trial. Kuru B, Yıldırım S 2013

The authors concluded that gingival unit grafts can be used  as an alternative technique for treating buccal gingival recessions with better defect coverage, clinical, and esthetic improvements compared with palatal grafts.

3. Gingival unit transfer using in the Miller III recession defect treatment. Selin Yıldırım and Bahar Kuru 2015

In this case report the clinical effectiveness of gingival unit transfer (GUT) technique performed on Miller III recession was presented and a similar recession case treated with free gingival graft (FGG) technique for comparison. The GUT revealed better defect coverage and creeping attachment results than the FGG in the treatment of Miller III defects.

4. Use of the gingival unit transfer in soft tissue grafting: report of three cases. Allen AL 2004

The gingival unit transfer is introduced through three case reports that describe its use for root coverage and replacement of intact but pathologically involved or esthetically compromised papillae. Supracrestal gingiva, used as a free graft for the above purposes, may have an uncommon capacity for perfusion and survival.

Aims and objectives:

1.     To compare the use of Gingival unit transfer with epithelialized palatal graft as a surgical modality for the treatment of localised Miller’s class I and class II gingival recession defects over a six month period.

2.     

Justification for study

Gingiva with its unique vasculature is naturally created to survive and function interproximally and facially over avascular root surfaces. Gingival unit graft, used as a free graft for recession coverage may have an uncommon capacity for perfusion and survival. More investigation is necessary to confirm the validity of this concept.

Methodology:

Bilateral sites in 22 patients with miller’s class 1 and class 2 recession, will be randomly assigned to recieve epithelialized palatal graft or gingival unit grafts. Plaque and gingival index will be scored at baseline after scaling, at 4 weeks and subsequently at every post surgical visit of the patient. Post surgery ,the patients will be recalled every two weeks for the first two months and once every month thereafter for six months. Recession depth, recession width, probing depth, keratinised gingiva width, clinical attachment level both at donor and recipient site will be recorded at baseline 1 month, 3 months and six months.Supra gingival polishing at each of these visits may be done as required. 

Potential risks & benefits:

Gingival unit graft technique is relatively safer when compared to the free gingival graft as it is at a more safer distance from greater palatine artery.