Zygomatic arch

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Zygomatic arch
Gray188-Sphenozygomatic suture.png
Side view of the skull.
Processuszygomaticusossisfrontalis.PNG
Articulation of the mandible. Lateral aspect.
Details
Identifiers
Latin arcus zygomaticus
MeSH D015050
TA98 A02.1.00.023
TA2 427
FMA 53120
Anatomical terminology

In anatomy, the zygomatic arch, or cheek bone, is a part of the skull formed by the zygomatic process of the temporal bone (a bone extending forward from the side of the skull, over the opening of the ear) and the temporal process of the zygomatic bone (the side of the cheekbone), the two being united by an oblique suture (the zygomaticotemporal suture); [1] the tendon of the temporal muscle passes medial to (i.e. through the middle of) the arch, to gain insertion into the coronoid process of the mandible (jawbone).

Contents

The jugal point is the point at the anterior (towards face) end of the upper border of the zygomatic arch where the masseteric and maxillary edges meet at an angle, and where it meets the process of the zygomatic bone.[ clarification needed ]

The arch is typical of Synapsida ("fused arch"), a clade of amniotes that includes mammals and their extinct relatives, such as Moschops and Dimetrodon .

Structure

The zygomatic process of the temporal arises by two roots:

The upper border of the arch gives attachment to the temporal fascia; [2] the lower border and medial surface give origin to the masseter.

Society and culture

High cheekbones are pronounced zygomatic arches, causing the upper part of the cheeks to jut out and form a line cut into the sides of the face. High cheekbones, forming a symmetrical face shape, are very common in fashion models and may be considered a beauty trait in both males and females within Eurocentric beauty standards. [3]

Etymology

The zygomatic arch on a man Zygomatic-arch.jpg
The zygomatic arch on a man

The term zygomatic derives from the Greek ζύγωμα zygōma, meaning "bolt, bar", derived from ζυγο-, "yoke, join". The Greek word was already used with this anatomical sense by Galen (2.437, 746) in the 2nd century AD. The zygomatic arch is occasionally referred to as the zygoma, but this term usually refers to the zygomatic bone or occasionally the zygomatic process.

Other animals

The zygomatic arch is significant in evolutionary biology, as it is part of the structures derived from the ancestral single temporal fenestra of the synapsid ancestor of mammals.

Additional images

See also

Related Research Articles

<span class="mw-page-title-main">Maxilla</span> Upper jaw bone

The maxilla in vertebrates 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 which articulates with the maxilla, the temporal bone, the sphenoid bone and the frontal bone. It is situated at the upper and lateral part of the face and forms the prominence of the cheek, part of the lateral wall and floor of the orbit, and parts of the temporal fossa and the infratemporal fossa. It presents a malar and a temporal surface; four processes, and four borders.

<span class="mw-page-title-main">Sphenoid bone</span> Bone at the front of the skull

The sphenoid bone is an unpaired bone of the neurocranium. It is situated in the middle of the skull towards the front, in front of the basilar part of the occipital bone. The sphenoid bone is one of the seven bones that articulate to form the orbit. Its shape somewhat resembles that of a butterfly or bat with its wings extended.

<span class="mw-page-title-main">Occipital bone</span> Saucer-shaped membrane bone situated at the back and lower part of the cranium

The occipital bone is a cranial dermal bone and the main bone of the occiput. It is trapezoidal in shape and curved on itself like a shallow dish. The occipital bone overlies the occipital lobes of the cerebrum. At the base of the skull in the occipital bone, there is a large oval opening called the foramen magnum, which allows the passage of the spinal cord.

<span class="mw-page-title-main">Temporal bone</span> Sides and base of skull, connecting to the jaw and occipital bone

The temporal bones are situated at the sides and base of the skull, and lateral to the temporal lobes of the cerebral cortex.

<span class="mw-page-title-main">Orbit (anatomy)</span> Cavity or socket of the skull in which the eye and its appendages are situated

In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. "Orbit" can refer to the bony socket, or it can also be used to imply the contents. In the adult human, the volume of the orbit is 30 millilitres, of which the eye occupies 6.5 ml. The orbital contents comprise the eye, the orbital and retrobulbar fascia, extraocular muscles, cranial nerves II, III, IV, V, and VI, blood vessels, fat, the lacrimal gland with its sac and duct, the eyelids, medial and lateral palpebral ligaments, cheek ligaments, the suspensory ligament, septum, ciliary ganglion and short ciliary nerves.

<span class="mw-page-title-main">Masseter muscle</span> One of the masticatory muscles in mammals

In human anatomy, the masseter is one of the muscles of mastication. Found only in mammals, it is particularly powerful in herbivores to facilitate chewing of plant matter. The most obvious muscle of mastication is the masseter muscle, since it is the most superficial and one of the strongest.

<span class="mw-page-title-main">Temporal fossa</span>

The temporal fossa is a fossa on the side of the skull bounded by the temporal lines and terminating below the level of the zygomatic arch.

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<span class="mw-page-title-main">Condyloid process</span>

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">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; 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">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">Tympanic part of the temporal bone</span> Middle part of the sides of the skull base, surrounding the ear canal

The tympanic part of the temporal bone is a curved plate of bone lying below the squamous part of the temporal bone, in front of the mastoid process, and surrounding the external part of the ear canal.

<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">Zygomaticotemporal suture</span> Cranial suture between the zygomatic bone and the temporal bone

The zygomaticotemporal suture is the cranial suture between the zygomatic bone and the temporal bone. This is part of the zygomatic arch. Movement at the suture decreases with development during aging. It has a complex internal structure.

<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">Zygomatic process</span>

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

<span class="mw-page-title-main">Coronoid process of the mandible</span>

In human anatomy, the mandible's coronoid process is a thin, triangular eminence, which is flattened from side to side and varies in shape and size. Its anterior border is convex and is continuous below with the anterior border of the ramus. Its posterior border is concave and forms the anterior boundary of the mandibular notch. The lateral surface is smooth, and affords insertion to the temporalis and masseter muscles. Its medial surface gives insertion to the temporalis, and presents a ridge which begins near the apex of the process and runs downward and forward to the inner side of the last molar tooth.

<span class="mw-page-title-main">Mandible</span> Lower jaw bone

In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. It is the only movable bone of the skull. It is connected to the temporal bones by the temporomandibular joints.

<span class="mw-page-title-main">Zygomaticomaxillary complex fracture</span> Medical condition

The zygomaticomaxillary complex fracture, also known as a quadripod fracture, quadramalar fracture, and formerly referred to as a tripod fracture or trimalar fracture, has four components, three of which are directly related to connections between the zygoma and the face, and the fourth being the orbital floor. Its specific locations are the lateral orbital wall (at its superior junction with the zygomaticofrontal suture or its inferior junction with the zygomaticosphenoid suture at the sphenoid greater wing, separation of the maxilla and zygoma at the anterior maxilla, the zygomatic arch, and the orbital floor near the infraorbital canal.

References

PD-icon.svgThis article incorporates text in the public domain from page 183 of the 20th edition of Gray's Anatomy (1918)

  1. Herring, Susan W.; Mucci, Robert J. (1991). "In vivo strain in cranial sutures: The zygomatic arch". Journal of Morphology. 207 (3): 225–239. doi:10.1002/jmor.1052070302. ISSN   0362-2525. PMC   2814820 . PMID   1856873.
  2. Abul-Hassan HS, von Drasek Ascher G, Acland RD (January 1986). "Surgical anatomy and blood supply of the fascial layers of the temporal region". Plastic and Reconstructive Surgery . 77 (1): 17–28. doi:10.1097/00006534-198601000-00004. PMID   3941846. S2CID   34872321.
  3. Sex and Society. Marshall Cavendish. September 2009. p. 91. ISBN   978-0-7614-7906-2 . Retrieved 2 November 2012.