Orbital lamina of ethmoid bone
Encyclopedia
The lamina papyracea is a smooth, oblong bone plate which forms the lateral surface of the labyrinth of the ethmoid bone
Ethmoid bone
The ethmoid bone is a bone in the skull that separates the nasal cavity from the brain. As such, it is located at the roof of the nose, between the two orbits. The cubical bone is lightweight due to a spongy construction. The ethmoid bone is one of the bones that makes up the orbit of the eye...

 in the skull
Human skull
The human skull is a bony structure, skeleton, that is in the human head and which supports the structures of the face and forms a cavity for the brain.In humans, the adult skull is normally made up of 22 bones...

.
The plate covers in the middle and posterior ethmoidal cells and forms a large part of the medial wall of the orbit
Orbit (anatomy)
In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. "Orbit" can refer to the bony socket, or it can also be used to imply the contents...

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It articulates above with the orbital plate of the frontal bone
Frontal bone
The frontal bone is a bone in the human skull that resembles a cockleshell in form, and consists of two portions:* a vertical portion, the squama frontalis, corresponding with the region of the forehead....

, below with the maxilla
Maxilla
The maxilla is a fusion of two bones along the palatal fissure that form the upper jaw. This is similar to the mandible , which is also a fusion of two halves at the mental symphysis. Sometimes The maxilla (plural: maxillae) is a fusion of two bones along the palatal fissure that form the upper...

 and the orbital process of palatine bone
Orbital process of palatine bone
The orbital process of the palatine bone is placed on a higher level than the sphenoidal, and is directed upward and lateralward from the front of the vertical part, to which it is connected by a constricted neck. It presents five surfaces, which enclose an air cell...

, in front with the lacrimal
Lacrimal
The term Lacrimal can refer to:*In typography:** A type of Stroke ending *In anatomy** Lacrimal apparatus** Lacrimal artery** Lacrimal bone...

, and behind with the sphenoid
Sphenoid bone
The sphenoid bone is an unpaired bone situated at the base of the skull in front of the temporal bone and basilar part of the occipital bone.The sphenoid bone is one of the seven bones that articulate to form the orbit...

.

Its name lamina papyracea is a literal description, as this part of the ethmoid bone is paper-thin and fractures easily.
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