Previously failed implant, removed, good healing of bone, significant amount of soft tissue noted in site of previous ostoetomy, after cleaning, communication into sinus chamber and sinus membrane perforation noted, prf fibrin placed against sinus floor folloewd by collagen membrane soaked in prf fluid, shorter implant placed (6mm, sinus floor is at 8mm) some difficulty in getting implant to desired depth, had to reprep osteotomy slightly, healing abutment placed