Unusual complication of orbital floor blow-out fracture repair.

An unusual complication of repair of orbital floor blow-out fracture is reported. The supramid plate eroded partially through the orbital floor into the maxillary sinus creating a springboard-like mechanism. When the pressure in the maxillary sinus increased, the posterior portion of the supramid plate was pushed upward. This motion of the plate displaced the eye forward and somewhat outward as well as upward. Following the resection of the portion of the plate protruding into the orbit, the symptoms disappeared.