The flap used is dependent on the size and position of the defect. Buccal advancement flap
The buccal advancement flap is the most commonly used due to its simplicity, reliability and versatility. It involves cutting a broad based trapezoid shaped mucoperiosteal flap with two vertical incisions. The flap is cut buccally, is three sided and extends to the full depth of the sulcus. Buccal fat pad flap
The buccal fat pad flap is also a popular option due to its high success rate. It is a simple procedure where the buccal extension of the anatomical fat pad is used for closure. These two flaps can be used in combination where the buccal fat pad covers the communication followed by a further covering via the buccal mucosal flap described above. This double layer flap has advantages over a single layer as it provides stable soft tissue covering, reduces the incidences of wound breakdown and defect recurrence as well as reducing the risk of postoperative infection.Sutures, either non-resorbing or slowly resorbing, are generally used in the surgical repairs of OAC. Non-surgical interventions
Ultimately, surgery is usually required to close an OAC/OAF. However, if surgery is not immediately available then non-surgical methods can be used to encourage the growth of oral mucosa between the oral cavity and the antrum. The aim of these methods is to protect the blood clot within the socket and help to prevent infection.
The maxillary sinus is connected to the nose and therefore fluid can come out of the nostrils when drinking· Change in sounds produced from the nose and the voice – specifically a whistling sound whilst speaking· Taste can be affected

Signs
· Visible hole between mouth and sinus
· Fracture of the floor of the maxillary sinus creating a communication to the oral cavity (e.g. as seen following trauma).· Air bubbles, blood or mucoid secretion around the orifice can be seen as air passes from the sinus into the oral cavity through the communication. Diagnosis
- Patient history - Diagnosis is usually based on clinical examination and reported symptoms. Therefore, a good history and understanding of the patient’s symptoms is key. - Undertake a complete extraoral and intraoral examination using a dental mirror alongside good lighting. When assessing the socket following an extraction look for granulation tissue in the socket which may represent normal healing. Assess for the presence of visible an opening/hole between the oral cavity and the maxillary sinus. - Imaging can be useful. However, radiographs only show if there is a breach in the bony floor of the antrum. Even if there is a breach in the bony floor then the Schneiderian membrane may still be intact. Depending on the size of the potential communication and in what context, a small radiograph inside the mouth may be sufficient (a periapical) to assess for any break in the bone of the sinus floor which may indicate an OAC.