(1) Zygomatic process. This is a projection from the center of the lateral
aspect of each temporal bone. (A process is an extension or projection from a bone.) It
extends forward from the top of the meatus to join the zygomatic bone of the face. This
extension forms a part of the zygomatic arch (cheekbone) and can be felt with the
fingers. The zygomatic process is often involved in facial fractures.
(2) Temporomandibular joint. On the under surface of the zygomatic
process, just in front of the ear, is a depression called the mandibular or glenoid fossa.
(A fossa is a hollow area or depression in a bone.) This fossa and the condyle (a
rounded prominence at the end of a bone) of the mandible (the lower jaw) form the
temporomandibular joint. Movements of the joint can be felt if the fingers are placed
just below and in front of the ear canal when the mouth is opened and closed. It is
sometimes referred to as the TMJ.
(3) Mastoid process. This projection of the temporal bone may be felt as a
knob of bone jutting down behind the ear. The mastoid process contains spaces called
mastoid air cells. These air cells communicate with the middle ear. The mastoid
process serves as an attachment for several muscles which move the head.
2-4.
FACE
The face is an extremely important part of the anatomy. It has a wide range of
attributes which involve your appearance and essential activities, such as swallowing,
seeing, and breathing. Many tissues of the face are involved in dental treatment, and
the dental specialist must have a thorough understanding of this anatomical area.
Since the bones of the jaws (the maxilla and the mandible) are of special interest in
dentistry, they are considered in separate paragraphs. Other bones are presented in
"a" through "f" below. Of these, the first two are used as landmarks for dental
radiographs. The 14 bones of the face are listed in table 2-1.
Mandible
1 Bone
Maxillae
2 Bones (plural of maxilla)
Zygomatic
2 Bones
Lacrimal
2 Bones
Nasal
2 Bones
Inferior nasal conchae
2 Bones
Palatine
2 Bones
Vomer
1 Bone
Table 2-1. Bones of the face.
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2-5