A narrative literature review of articles and case reports for oroantral fistula has been conducted in the PubMed databases of published English literature. Articles published until April 2018 were reviewed. In addition to 262 articles on the closure of oroantral, 4 articles on the closure of antrooral fistula in humans, and 5 articles in animals, citations were referenced to identify further relevant articles. According to Visscher’s classification, the treatment strategies for OAFs closure can be broadly categorized into autogenous soft tissue grafts, autogenous bone grafts, allogenous materials, xenografts, synthetic closure, and other techniques [10] (Fig. 1). New techniques were included in this classification. The studies and number of cases are listed in Table 1.

Closure of OAF can be achieved using different flap techniques, each of which presents both advantages and limitations. Three types of flaps are most widely used: a buccal flap, a buccal fat pad (BFP) flap, and a palatal flap.

In 1936, Rehrmann [11] described the use of a buccal advancement flap. Krompotie and Bagatin reported that the rotating gingivovestibular flap can also be applied for closure of an antrooral fistula. This technique is a modification of a vestibular flap with the aim of preventing the lowering of the vestibular sulcus, which regularly accompanies the application of vestibular flaps [12]. The flap with its simplicity, reliability, and versatility is the most commonly used method for OAF closure [5, 13].

In this technique, a broad-based trapezoid mucoperiosteal flap is created after excising the epithelialized margins and giving two vertical release incisions to develop a flap with adequate dimensions to be sutured over the defect. Its broad base enables a better blood supply to the flap. Flap coverage is improved by horizontal periosteal incisions. Falci et al. described a modification of this technique for OAF closure. The mucosal margins of the fistula were sutured together prior to the reflection of the buccal flap. Then, the buccal flap was pulled over this sutured site and tucked under the palatal flap, which was elevated simultaneously with the buccal flap [13]. Killey, in 1972, studied 362 cases using this technique. The results revealed success in 336 (93%) cases [5]. However, the potential disadvantage of using this flap for OAF closure is the reduction of buccal sulcus, which makes it difficult to use prosthesis in the future [1]. Other disadvantages include postoperative pain and swelling as a result of the reflection of a mucoperiosteal flap. Currently, a reduction in the buccal sulcus can be overcome by implant-retained overdentures.