Dental implant migration in grafted maxillary sinus.

BACKGROUND: Migration of oral implants through a previously consolidated graft is an extremely rare event. We reported 2 cases of migration at least 6 months postimplantation in sinus grafted in 2 stages, consequently over 6-month graft maturation period. CASE DESCRIPTION: Sinus elevations and implants placement in 2 patients were performed. Clinical and radiographic follow-up after the prosthetic rehabilitation showed displacement of 1 implant in each patient through the histopathologically verified stable grafts. CLINICAL IMPLICATIONS: Implants migration through composite graft after maxillary sinus elevation was reported. Reasons for this to occur might be due to the following: fail to achieve implant primary stability, Schneiderian membrane perforation, or graft resorption due to increased osteoclastic activity.