Zygomatic process

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The zygomatic process forms an "L" in this picture. Gray164.png
The zygomatic process forms an "L" in this picture.
As a comparison, this is how the skull looks with almost all of the zygomatic process removed. Gray189.png
As a comparison, this is how the skull looks with almost all of the zygomatic process removed.

The zygomatic processes (aka. malar) are three processes (protrusions) from other bones of the skull which each articulate with the zygomatic bone. The three processes are: [1]

Contents

The term zygomatic derives from Greek ζύγωμα (zúgōma) 'yoke'. The zygomatic process is occasionally referred to as the zygoma, but this term usually refers to the zygomatic bone or occasionally the zygomatic arch.

Zygomatic process of frontal bone

Zygomatic process of frontal bone
Gray136.png
Frontal bone at birth (Zygomatic process visible at lower right)
Details
Identifiers
Latin processus zygomaticus ossis frontalis
Anatomical terms of bone

The supraorbital margin of the frontal bone ends laterally in its zygomatic process, which is strong and prominent, and articulates with the zygomatic bone. The zygomatic process of the frontal bone extends from the frontal bone laterally and inferiorly.

Zygomatic process of maxilla

Zygomatic process of maxilla
Zygomatic process of maxilla - skull - anterior view.png
Zygomatic process shown in red
Gray164 - Zygomatic process of maxilla.png
Left zygomatic bone in situ (Zygomatic process of maxilla is shown in yellow.)
Details
Identifiers
Latin processus zygomaticus maxillae
Anatomical terms of bone

The zygomatic process of the maxilla [2] is a rough triangular eminence, situated at the angle of separation of the anterior, zygomatic, and orbital surfaces.

Zygomatic process of temporal bone

Zygomatic process of temporal bone
Zygomatic process of temporal bone - lateral view.png
Zygomatic process shown in red
Processuszygomaticusossisfrontalis.PNG
Articulation of the mandible. Lateral aspect (Zygomatic process visible at center)
Details
Identifiers
Latin processus zygomaticus ossis temporalis
Anatomical terms of bone

The zygomatic process of the temporal bone is a long, arched process projecting from the lower part of the squamous portion of the temporal bone. It articulates with the zygomatic bone.

This process is at first directed lateralward, its two surfaces looking upward and downward; it then appears as if twisted inward upon itself, and runs forward, its surfaces now looking medialward and lateralward.

The superior border is long, thin, and sharp, and serves for the attachment of the temporal fascia.

The inferior border, short, thick, and arched, has attached to it some fibers of the masseter.

The lateral surface is convex and subcutaneous. The medial surface is concave, and affords attachment to the masseter.

The anterior end is deeply serrated and articulates with the zygomatic bone. The posterior end is connected to the squama by two roots, the anterior and posterior roots:

Processes of the zygomatic bone

The zygomatic bone itself has four processes, namely the frontosphenoidal, orbital, maxillary and temporal processes.

The frontosphenoidal process is thick and serrated. The cranial suture between the frontal and zygomatic bone is found here. On its orbital surface, just within the orbital margin and about 11 mm below the zygomaticofrontal suture is a tubercle of varying size and form, but present in 95 per cent of skulls (Whitnall 43). This tubercle is not seen in the picture.

The orbital process is a thick, strong plate, projecting backward and medialward from the orbital margin. It is the gloomy area beneath the lac(rimal) and ethmoidal bones in the image.

The maxillary process presents a rough, triangular surface which articulates with the maxilla. It is the area below "zygomatic" in the image.

The temporal process, long, narrow, and serrated, articulates with the zygomatic process of the temporal. It is the process to the right of "zygomatic" in the image.

Additional images

See also

Related Research Articles

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In vertebrates, the maxilla is the upper fixed bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxillary bones are fused at the intermaxillary suture, forming the anterior nasal spine. This is similar to the mandible, which is also a fusion of two mandibular bones at the mandibular symphysis. The mandible is the movable part of the jaw.

<span class="mw-page-title-main">Zygomatic bone</span> Facial bone

In the human skull, the zygomatic bone, also called cheekbone or malar bone, is a paired irregular bone, situated at the upper and lateral part of the face and forming part of the lateral wall and floor of the orbit, of the temporal fossa and the infratemporal fossa. It presents a malar and a temporal surface; four processes, and four borders.

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In the human skull, the frontal bone or sincipital bone is a unpaired bone which consists of two portions. These are the vertically oriented squamous part, and the horizontally oriented orbital part, making up the bony part of the forehead, part of the bony orbital cavity holding the eye, and part of the bony part of the nose respectively. The name comes from the Latin word frons.

<span class="mw-page-title-main">Inferior nasal concha</span> Facial bone

The inferior nasal concha is one of the three paired nasal conchae in the nose. It extends horizontally along the lateral wall of the nasal cavity and consists of a lamina of spongy bone, curled upon itself like a scroll,. The inferior nasal conchae are considered a pair of facial bones. As the air passes through the turbinates, the air is churned against these mucosa-lined bones in order to receive warmth, moisture and cleansing. Superior to inferior nasal concha are the middle nasal concha and superior nasal concha which both arise from the ethmoid bone, of the cranial portion of the skull. Hence, these two are considered as a part of the cranial bones.

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In anatomy, the zygomatic arch, or cheek bone, is a part of the skull formed by the zygomatic process of the temporal bone and the temporal process of the zygomatic bone, the two being united by an oblique suture ; the tendon of the temporal muscle passes medial to the arch, to gain insertion into the coronoid process of the mandible (jawbone).

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<span class="mw-page-title-main">Process (anatomy)</span> Projection or outgrowth of tissue from a larger body

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The temporal fossa is a fossa on the side of the skull bounded by the temporal lines above, and the zygomatic arch below. Its floor is formed by the outer surfaces of four bones of the skull. The fossa is filled by the temporalis muscle.

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<span class="mw-page-title-main">Condyloid process</span> Part of the jawbone which hinges it to the skull

The condyloid process or condylar process is the process on the human and other mammalian species' mandibles that ends in a condyle, the mandibular condyle. It is thicker than the coronoid process of the mandible and consists of two portions: the condyle and the constricted portion which supports it, the neck.

<span class="mw-page-title-main">Pterygoid processes of the sphenoid</span> Bone plates projecting from the sphenoid bone of the skull

The pterygoid processes of the sphenoid, one on either side, descend perpendicularly from the regions where the body and the greater wings of the sphenoid bone unite.

<span class="mw-page-title-main">Greater wing of sphenoid bone</span> Large part of the skull front behind the eye socket

The greater wing of the sphenoid bone, or alisphenoid, is a bony process of the sphenoid bone, positioned in the skull behind each eye. There is one on each side, extending from the side of the body of the sphenoid and curving upward, laterally, and backward.

<span class="mw-page-title-main">Ethmoidal labyrinth</span>

The ethmoidal labyrinth or lateral mass of the ethmoid bone consists of a number of thin-walled cellular cavities, the ethmoid air cells, arranged in three groups, anterior, middle, and posterior, and interposed between two vertical plates of bone; the lateral plate forms part of the orbit, the medial plate forms part of the nasal cavity. In the disarticulated bone many of these cells are opened into, but when the bones are articulated, they are closed in at every part, except where they open into the nasal cavity.

<span class="mw-page-title-main">Squamous part of temporal bone</span> Front and upper part of the sides of the skull base

The squamous part of temporal bone, or temporal squama, forms the front and upper part of the temporal bone, and is scale-like, thin, and translucent.

<span class="mw-page-title-main">Lateral parts of occipital bone</span> Parts of bone in base of skull

The lateral parts of the occipital bone are situated at the sides of the foramen magnum; on their under surfaces are the condyles for articulation with the superior facets of the atlas.

<span class="mw-page-title-main">Squamous part of the frontal bone</span> Upper two-thirds of the forward skull

The squamous part of the frontal bone is the superior portion when viewed in standard anatomical orientation. There are two surfaces of the squamous part of the frontal bone: the external surface, and the internal surface.

<span class="mw-page-title-main">Infratemporal fossa</span> Cavity that is part of the skull

The infratemporal fossa is an irregularly shaped cavity that is a part of the skull. It is situated below and medial to the zygomatic arch. It is not fully enclosed by bone in all directions. It contains superficial muscles, including the lower part of the temporalis muscle, the lateral pterygoid muscle, and the medial pterygoid muscle. It also contains important blood vessels such as the middle meningeal artery, the pterygoid plexus, and the retromandibular vein, and nerves such as the mandibular nerve (CN V3) and its branches.

<span class="mw-page-title-main">Orbital process of palatine bone</span>

The orbital process of the palatine bone is placed on a higher level than the sphenoidal, and is directed upward and lateralward from the front of the vertical part, to which it is connected by a constricted neck. It presents five surfaces, which enclose an air cell. Of these surfaces, three are articular and two non-articular.

<span class="mw-page-title-main">Frontal process of maxilla</span> Plate which forms part of the lateral boundary of the nose

The frontal process of the maxilla is a strong plate, which projects upward, medialward, and backward from the maxilla, forming part of the lateral boundary of the nose.

References

  1. Marieb & Hoehn's (2010) Human Anatomy & Physiology
  2. Google Books: zygomatic process of the maxilla: Exercises in Oral Radiology and Interpretation – E-Book (Elsevier Health Sciences, Dec 12, 2003, by Robert P. Langlais) – Retrieved 2018-08-26

PD-icon.svgThis article incorporates text in the public domain from the 20th edition of Gray's Anatomy (1918)