Resident Manual of Trauma to the Face, Head and Neck

3. Nasal Bones The nasal bones project from the frontal processes of the maxillae and form the bony support of the upper portion of the nose (Figure 4.2). They connect the midface to the skull (frontal bones) anteriorly in the midline.

Figure 4.2 Illustration depicting frontal view of the skull. Source: Agur and Dalley, Figure 459 .

4. Orbits The orbits have a four-walled pyramidal shape, with the apex located medial and superior. a. Lacrimal, Ethmoid, and Palatine Bones The optic canal is at the apex and transmits the optic nerve. The medial wall is composed of the thick lacrimal bone, which supports the lacrimal sac; the thin lamina papyracea of the ethmoid bone; and, to a smaller extent, the palatine bone. b. Sphenoid Bone The medial wall of the optic canal is provided by the strong lesser wing of the sphenoid bone. The floor is composed primarily of the thin roof of the maxillary sinus.

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