This study aimed to assess the clinical outcome of a designated approach purpose to reconstruct large oro-antral fistulae combining tripled layer soft tissue closure along with later sinus lifting and bone grafting. The study constituted of three non-smokers male patients, which were subjected to failed previous surgical closures of large oro-antral fistulae, with a subsequent maxillary sinus infection and morbid vascular bed. After definite eradication of the persisting infection, the large communications were planned to be restored by three soft tissue flaps, the first of which based on utilizing the dense epithelial fistulous sinus tract, which was crafted, instead of being eliminated and adapted to the underlying bony defect to represent a shield that sealed the defect, obliterated the dead space, withstood the postoperative fluid overload and supported the overlying pedicled fat pad and the buccal advancement flap, which represented the second and third layers of closure. Three months later, open sinus lifting and bone grafting of the defects were carried out. Although two patients complained significant postoperative pain, limitation of mouth opening and swelling, all the reconstructed defects healed uneventfully, none of them revealed postoperative infection, wound dehiscence or relapse throughout the investigation period, and the patients neither exhibited any sign of recurrent maxillary sinusitis nor graft failure, furthermore, C.B.C.T. six months postoperatively, demonstrated that the reconstructed defects are well organized to receive proper sized dental implants. The authors recommend implementing this study over a broadened sample size, as this study was restrained by the small number of participants.