الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 112 |  |  |
| | | from | 112 | | |
Abstract
OAFs are pathological communications between the oral cavity and maxillary sinus. This complication occurs most commonly during extraction of upper molar and premolar teeth. Different surgical techniques were introduced to close OAFs, however most of these techniques depend on soft tissue closure only without grafting the bony defect of the OAF. Soft tissue closure has high recurrence rate of the fistula especially in large bone defects and also, because of the continued need for implant rehabilitation and preimplant surgery, such as sinus floor elevation and ridge augmentation, routine soft tissue closure of OAFs has become a major problem, as it causes matting of the oral mucosa and the schneiderian membrane, which makes elevation of the sinus membrane impossible without tearing it. So, closure of OAF with autogenous or allogenous bone graft is recommended. For this purpose, this study was carried out on twelve patients complaining from oroantral fistulas following extraction of maxillary posterior teeth and indicated for surgical closure. Patients were collected from department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Tanta University. The sinus linning was repaired using the fitsulous tract which dissected and rotated into the sinus membrane, then the bony defect was grafted with autogenous corticocancellous chin graft and platelet- rich fibrin (PRF) membrane and the graft was covered with buccal advancement flap. The patients were followed up : Clinically: after 1, 2 weeks, 1,3 and 6 months to evaluate successful closure of the fistula without any signs of infection, wound dehiscence, graft exposure or fluid regurgitation from the nose after drinking. Radiographically: was performed immediate and 6 months postoperatively using C.B.C.T to evaluate the vertical bone height and bone density of the graft. Successful closure of the OAF was achieved in 11 cases. These patients showed no signs of wound dehiscence, infection, ulceration or exposure of the graft. Also, no fluid regurgitation from the nose after drinking and no signs of maxillary sinusitis. Only one case (case no. 3) showed wound dehiscence and graft exposure one week postoperatively and the wound not healed so, the graft was removed and the wound was closed with buccal advancement flap. Radiographically: radiographic evaluation using C.B.C.T after 6 months when compared to immediately after surgery showed complete healing of the bone defect with non- significant increase in bone density and non-significant decrease in alveolar bone height. from the results of this study, we can conclude that: - Bony closure of the OAF is recommended to provide bony base for subsequent Implant placement. - Epithelialized fistulous tract can be dissected and rotated to be used for repairing the sinus membrane. - Combined press- fitted closure of the OAF with autogenous chin graft and PRF membrane which covered with buccal advancement flap provides successful three- layered closure of the OAF and support healing of soft tissue flap.