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mandibular incisors, yet the maxillary molar sits slightly posterior to the

mandibular molar.) Familiarity with what is normal is important when

repairing fractures in this area.

B. Midfacial Anatomy

The midfacial structure includes left and right paired, mirror-image

bones that make up the orbits, nasal structure, cheekbones, maxillae

(which hold the upper teeth), and palate. Of course, multiple bones

contribute to the orbital structure, including the maxilla, zygoma,

sphenoid (both greater and lesser wing components), frontal, ethmoid,

lacrimal, and palatine bones (Figure 4.1).

Figure 4.1

Illustration depicting orbital structure. Source: Agur and Dalley, Figure 518.

The bones of the face provide support for important physiologic

functions, including support of the nasal airway and olfaction, support

and protection of the globes and visual function, and support for the

teeth and masticatory function. It has also been suggested that the

facial bone structure includes strong areas (buttresses) that support

the anatomy and provide the strength needed for masticatory function,

and that these areas are separated by weaker areas that provide

protection for important structures, such as the eyes and the brain

(Manson, Stanley). (It has been theorized that the paranasal sinuses

may function as “crumple zones” or shock absorbers that can protect

the eyes, optic nerves, carotid arteries, and brain from some blunt

traumas (Kellman, Kellman & Schmidt).) The midface is suspended

from the skull base, and posteriorly, the pterygoid plates complete the

midfacial structure.