Resident Manual of Trauma to the Face, Head and Neck

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.

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