Periodontitis is the sixth most prevalent disease worldwide. If not treated, it may lead to the destruction of the periodontal soft and hard tissues, which in turn may lead to the root surface being exposed to the oral environment, and multiple gingival recessions showing up in patients with periodontitis. Gingival recession is defined as the displacement of marginal tissue apical to the cemento-enamel junction (CEJ). Miller proposed a classification system in 1985 that is probably most widely used for describing the gingival recession.  Class I: Marginal tissue recession not extending to the mucogingival junction (MGJ). No loss of interdental bone or soft tissue Class II: Marginal recession extending to or beyond the MGJ. No loss of interdental bone or soft tissue  Class III: Marginal tissue recession extends to or beyond the MGJ. Loss of interdental bone or soft tissue is apical to the CEJ, but coronal to the apical extent of the marginal tissue recession  Class IV: Marginal tissue recession extends to or beyond the MGJ. Loss of interdental bone extends to a level apical to the extent of the marginal tissue recession. Aggressive tooth brushing contributes to gingival recession in several teeth, especially in individuals with a greater awareness of oral hygiene. Poor oral hygiene, lack of keratinized gingiva, thin tissue phenotype, smoking, aberrant frenal attachment, tooth position in the arch, and age are some risk factors (Cortellini and Bissada, 2018). Long-term root exposure caused by the untreated gingival recession may result in further recession, dentinal sensitivity, cervical abrasion, root caries, and poor aesthetics (Cortellini & Bissada, 2018, Chambrone & Tatakis, 2016)Ectopic insertion of frenulum, Malpositioned teeth, and muscle attachments also contribute to gingival recession.The ultimate goal of root coverage procedure is the complete coverage of the recession defect with good appearance related to adjacent soft tissues and minimal probing depth. This search for predictable aesthetic outcomes has led to the development of several new and modified surgical techniques in this past decade. Different tunnel techniques have been attempted for management of recession defects which maintain better blood supply and critical papillary integrity. Recent systematic reviews have identified advantages for autogenous subepithelial connective tissue grafts (CTGs) regarding root coverage and increased width of keratinized tissue. Some of the limitations of current techniques include the need for harvesting of autogenous donor tissues and their associated morbidity, as well as scar formation at the recipient site resulting from surface incisions. Moreover, muscle pull during healing often leads to incomplete root coverage or relapse of the recession. In 2011, Zadeh H H modified the tunnel technique offering the so-called VISTA (Vestibular Incision sub periosteal Tunnel Access) technique for the treatment of multiple adjacent gingival recessions. VISTA corrects the defect by coronal repositioning the gingival margin and establishing a subperiosteal tunnel with access near the Frenum. Lee et al in 2015 came up with the Modified form of VISTA (MVISTA), a microsurgical procedure, that aims at comprehensive root coverage maintaining the inner continuity of the periosteum and papilla. This technique incorporates any regenerative graft material within the tunnel. MVISTA is less invasive since tiny access incisions are created in the vestibule beyond the mucogingival junction. The main modifications in MVISTA consist of extending the vertical incision slightly beyond the mucogingival line, performing intrasulcular incision, and releasing the tunnel-papillae complex completely to facilitate the coronal traction of the whole tunnel-graft-papillae complex.

Platelet-rich fibrin (PRF), a second-generation platelet concentrate, is obtained from autologous blood with simplified processing without the need for biochemical blood handling. The processing of PRF involves the sequestration and concentration of platelets in autologous whole blood through centrifugation and natural polymerization. It activates the vascular system and releases growth factors involved in soft tissue healing. PRF also contains a large quantity of platelet and leukocyte cytokines, which can play a significant role in the self-regulation of inflammatory and infectious phenomena. PRF membrane has mechanical adhesive properties and biologic functions such as fibrin glue; it maintains the flap in a stable position and enhances angiogenesis. It is easy to produce and inexpensive and can be prepared in short duration. A-PRF is the most favourable form of platelet concentrate in regenerative periodontal therapy as it has a sustained release of growth factors over time, which corresponds to the haemostatic and inflammatory phase of wound healing. The advent of low-speed centrifugation concept has rendered A-PRF with a three-dimensional architecture which has an increased number of cells including platelets and leukocytes (90% platelets and 50% leukocytes) when compared to their concentration in whole blood which help in release of higher concentration of growth factors including PDGF, VEGF, IGF, FGF, TGF-β (10) A-PRF influence bone and soft tissue regeneration, especially through the presence of monocytes/macrophages and their growth factors.

Recently, amnion membrane has provided new strategy to induce tissue regeneration in periodontal disorders. Bioresorbable amnion membrane, an allograft is a rich source of various growth factors such as epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), platelet derived growth factor (PDGF), insulin like growth factor (IGF-1), transforming growth factor (TGF-β), various collagen and non-collagen proteins, and stem cells, that inducing varied biological effects such as anti-inflammatory, immune-modulatory, antimicrobial and antiviral properties and accelerating regeneration. Also, the other advantages of Amnion membrane include lack of immune responses in recipients, availability, and cost-effectiveness 

Till date no study has been conducted comparing the clinical efficacy of Modified Vestibular Incision Sub-Periosteal Tunnel Access (MVISTA) with Advanced Platelet-rich Fibrin (A-PRF) and Modified Vestibular Incision Sub-Periosteal Tunnel Access (MVISTA) with Amnion membrane in the treatment of multiple Millers class I and II gingival recession. Thus, the present study attempts to compare the clinical efficacy of Modified Vestibular Incision Sub-Periosteal Tunnel Access with Advanced Platelet-rich Fibrin and Modified Vestibular Incision Sub-Periosteal Tunnel Access with Amnion membrane in the treatment of multiple Millers class I and II gingival recession.