A Hinge Flap to Reinforce Buccal Advancement Flap

Background The chronic oroantral fistulas (COAF) is an epithelized communication that is formed between the squamous epithelium of the oral cavity and the pseudo-stratified columnar ciliated epithelium of the maxillary sinus with a high recurrent rate. The use of palatal flaps has been documented for treating such fistulae. The presence of the oroantral fistula at the area of second molars or maxillary tuberosity could complicate the use of the palatal rotational flap where the arch of its rotation is increased leading to compromised blood supply. The use of the buccal flap is not advocated because it is very thin. Rationale Double or triple-layer closure is indicated to avoid recurrence of the COAF. Different layers have been documented to minimize the risk of recurrence and reinforce buccal flaps. The oral tissues at the oral side of the oroantral fistula could used as an additional layer with buccal advancement flap and buccal fat to omit the use of palatal flap with its subsequent problems in the most posterior aspect of the maxilla Study objectives Therefore, this study will be conducted to evaluate the use of hinge flaps to reinforce the buccal advancement flap for surgical closure of the COAF in the most posterior area of the maxilla Methods The hinge flap will be performed at the oral side of the COAF to close the perforation in the sinus membrane. The oral side of the COAF will be closed with buccal advancement flap. The success rate, recurrence, time of surgery, postoperative complications, will be evaluated.

Inclusion Criteria: 1. Chronic oroantral fistula at the most posterior area of the maxilla 2. Ages above 18 years 3. Patients who are medical free Exclusion Criteria: 1. Oroantral communications 2. Absence of sinus infection 3. Oroantral fistula which are resulted from tumor resections