How To: Oroantral Fistula Closure Using Double-Layered Flap

INTRODUCTION

An oroantral fistula (OAF) is a pathological and epithelialized pathway between the oral cavity and maxillary sinus due to extraction of the upper molars, dental infection, trauma, radiation therapy, osteomyelitis, orthognathic surgery, or dental implants. Extraction of upper molars and premolars extraction is considered the most common etiology of OAF (Int J Implant Dent. 2019;5:13; Maxillofac Plastic Reconstr Surg. 2017;39:5; J Nat Sci Biol Med. 2012;3:203–205).

The aim of the OAF management is to repair the defect, restoring the integrity of the sinus and oral cavity and preventing sinus infections. Small fistulas (<5 mm) can heal spontaneously. However, OAF larger than 5 mm or those that have not been resolved within three months usually requires surgical treatment (Int J Implant Dent. 2019;5:13; Maxillofac Plastic Reconstr Surg. 2017;39:5). Choice of the technique for OAF closure depends on multiple factors such as the size, time of diagnosis, infection, height of the alveolar ridge, vestibular depth, further prosthetic treatment, and surgeon’s experience (Int J Implant Dent. 2019;5:). Many techniques have been described for OAF closure, including local and soft tissue flaps, grafts, alloplastic materials, biologics, and metals. However, a rational decision-making process must be followed to choose the most adequate technique (Int J Implant Dent. 2019;5:).

The buccal fat pad flap (BFP) is a simple and reliable flap for the treatment of OAF because of its rich blood supply and location (Maxillofac Plastic Reconstr Surg. 2017;39:5; J Nat Sci Biol Med. 2012;3:203–205). Its overall success rate for OAF closure is around 96.2% (Maxillofac Plastic Reconstr Surg. 2017;39:5). The principal limitation of BFP is the defect’s size because defects measuring more than 4 x 4 x 3 cm have a high risk of dehiscence (Maxillofac Plastic Reconstr Surg. 2017;39:5).

Our group previously described the use of a greater palatine artery (GPA) pedicled flap to repair nasal septal perforations with excellent results and minimal donor site morbidity (Facial Plast Surg Aesthet Med. 2020;22:301–303; Eur Arch Otorhinolaryngol. 2021;278:2115–2121).

This report presents a novel surgical technique for closure of large OAFs based on a combined endoscopic and transoral approach using a GPA pedicled flap and BFP.

METHOD

A 30-year-old man visited our emergency department with a history of four months of purulent nasal discharge and facial pain in the context of upper left molar extraction that did not respond to long-term antibiotic treatment. Nasal endoscopy showed purulent discharge coming from the left middle meatus and a bulging uncinate process. Oral cavity inspection manifested granulation tissue with purulent discharge at the site of tooth 26 (“FDI notation”). Facial and paranasal sinuses computed tomography (CT) was performed, it showed an 11 mm bone defect at the left maxillary floor concerning tooth 26 and a complete opacification of the maxillary sinus with osteomeatal complex obstruction.