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This chapter focuses on plays written by Georgia Douglas Johnson in the late 1920s as she hosted a literary salon in her Washington, D.C., home. These texts present the black mother/wife, whose existence is shaped by attempts to delay death. In Blue Blood, she prevents the murder of the men in her family by hiding the fact that she has been raped by a powerful white man. In Safe, she becomes desperate to avoid what she believes to be the inevitable fate of her newborn son: humiliating death at the hands of a mob. In Blue-Eyed Black Boy, she protects her adult son, but ultimately her success in stopping the mob underscores her family's vulnerability. In short, Johnson shows that the black mother/wife must forge romantic and parental bonds in a society that allows white men to rape black women and kill black men with impunity.

Some knowledge of the anatomy of the orbit is required by dental students and practitioners because it forms the upper part of the facial skeleton and some of the nerves and vessels supplying dental structures pass through it. Trauma to the middle third of the face, the upper facial skeleton, frequently involves the orbits and the structures they contain. Infections of the oral region occasionally spread to the orbit. In the following description, the emphasis is on those aspects of orbital anatomy of dental relevance; no description of the structure of the eyeball or the mechanisms of vision is included. The orbital cavities contain the eyeballs (globes), their associated muscles, vessels, nerves, the lacrimal apparatus, and a large amount of fat to cushion and protect the globes. Each cavity is pyramidal in shape. The base is the orbital opening on to the face; the roof, floor, and medial and lateral walls converge to the apex at the posterior aspect of the orbit. The long axis of the orbit from apex to surface runs forwards and laterally. The bones that form the orbit are illustrated in Figure 30.1 ; use the figure and a dried or model skull if possible as you read the following description. Most of the roof of the orbit is formed by the inferior surface of the orbital part of the frontal bone with a small posterior contribution from the lesser wing of the sphenoid ; this is pierced by the optic canal through which the optic nerve exits the orbit. The lateral wall is formed by the orbital surfaces of the zygomatic bone anteriorly and the greater wing of the sphenoid posteriorly. It separates the orbital cavity from the infratemporal fossa anteriorly and from the middle cranial fossa posteriorly. The floor of the orbit is occupied by the thin plate of bone forming the upper surface of the body of the maxilla ; this plate of bone is also the roof of the maxillary paranasal air sinus over most of its extent although the palatine bone forms a minute triangular area at the posteromedial corner.

It is essential that dental students and practitioners understand the structure and function of the temporomandibular joints and the muscles of mastication and other muscle groups that move them. The infratemporal fossa and pterygopalatine fossa are deep to the mandible and its related muscles; many of the nerves and blood vessels supplying the structures of the mouth run through or close to these areas, therefore, knowledge of the anatomy of these regions and their contents is essential for understanding the dental region. The temporomandibular joints (TMJ) are the only freely movable articulations in the skull together with the joints between the ossicles of the middle ear; they are all synovial joints. The muscles of mastication move the TMJ and the suprahyoid and infrahyoid muscles also play a significant role in jaw movements. The articular surfaces of the squamous temporal bone and of the condylar head (condyle) of the mandible form each temporomandibular joint. These surfaces have been briefly described in Chapter 22 on the skull and Figure 24.1A indicates their shape. The concave mandibular fossa is the posterior articulating surface of each squamous temporal bone and houses the mandibular condyle at rest. The condyle is translated forwards on to the convex articular eminence anterior to the mandibular fossa during jaw movements. The articular surfaces of temporomandibular joints are atypical; they covered by fibrocartilage (mostly collagen with some chondrocytes) instead of hyaline cartilage found in most other synovial joints. Figures 24.1B and 24.1C show the capsule and ligaments associated with the TMJ. The tough, fibrous capsule is attached above to the anterior lip of the squamotympanic fissure and to the squamous bone around the margin of the upper articular surface and below to the neck of the mandible a short distance below the limit of the lower articular surface. The capsule is slack between the articular disc and the squamous bone, but much tighter between the disc and the neck of the mandible. Part of the lateral pterygoid muscle is inserted into the anterior surface of the capsule. As in other synovial joints, the non-load-bearing internal surfaces of the joint are covered with synovial membrane.