(2.44)

The facial skeleton consists of a number of named bones. We’ll look at them individually later in this section, but we’ll start by looking at the main overall features of the facial skeleton. To simplify the picture, we’ll remove the mandible.

The cavity for the eye is called the orbital cavity. It’s protected on the outside by the thickened orbital margin. The opening for the nose leads to the right and left nasal cavities, which are separated by the nasal septum.

The upper jaw, or maxilla bears the upper teeth. The prominence of the cheek bone leads back to this bony arch, the zygomatic arch.

The deepening hollow here is the temporal fossa. It’s enclosed by this ridge, the temporal line, by the lateral orbital margin, and by the zygomatic arch. The temporal fossa contains the large temporalis muscle.

The temporal fossa is continuous with this deeper hollow, the infratemporal fossa. The walls of the infratemporal fossa are formed by this part of the base of the skull, and by the posterior part of the maxilla. The infratemporal fossa contains the pterygoid muscles, and also this part of the mandible, the coronoid process.

On the underside of the skull we come to structures that we’ve seen already. Here’s the foramen magnum, the basilar part of the occipital bone, and the petrous part of the temporal bone.

Two thin sheets of bone project down from the base of the skull behind the maxilla. They’re the pterygoid plates, lateral, and medial. Between the two medial pterygiod plates are the posterior openings of the nasal cavities, the posterior nares, or choanae.

The hard palate forms the roof of the mouth, and the floor of the nasal cavities. Here inside the nasal cavities are the conchae, or turbinate bones. We’ll look inside the nasal cavity in the next section.

The posterior nares open into the nasopharynx, which lies in the space between the medial pterygoid plates, the base of the occiput, and the anterior arch of the atlas vertebra.