bony anatomy of the orbit is composed of frontal bone, maxilla, zygomatic bone, sphenoid, ethmoid, lacrimal bone, and palatine bone. Frontal bone, maxilla, and zygomatic bone are particularly strong, but the walls of funnel-shaped orbit consist
in
part
of very thin bony lamellae, with only little resistance to trauma. These anatomic factors explain the very special fracture mechanisms that prevail in the orbital region, especially true blow-out fracture of the orbital floor.
In 1957, Smith and Regan originated the term blow-out fracture to describe a specific type of fracture of the orbital floor fracture of the orbital rim and with entrapment of one or more orbital soft tissue structures, thus limiting vertical
ocular
mobility and causing diplopia and enophthalmos.
At least four methods of rebuilding the orbital floor are commonly employed. These include repositioning of the displaced bones ; use of alloplastic graft material such as Marlex mesh, Silastic, and Teflon ; autogenous bone grafts ; homografts
such
as
lyophilized dura.
This report presents 3 cases of true blow-out fracture of the orbital floor that was treated by autogenous bone graft, especially thin transplants from anterior wall of the maxillary sinus.
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