In human anatomy, the
mandible
In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla).
The jawbone i ...
'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
In 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 ...
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
The molars or molar teeth are large, flat teeth at the back of the mouth. They are more developed in mammals. They are used primarily to grind food during chewing. The name ''molar'' derives from Latin, ''molaris dens'', meaning "millstone toot ...
.
Between this ridge and the anterior border is a grooved triangular area, the upper part of which gives attachment to the temporalis, the lower part to some fibers of the
buccinator.
Clinical significance
Fractures
Fracture is the appearance of a crack or complete separation of an object or material into two or more pieces under the action of stress (mechanics), stress. The fracture of a solid usually occurs due to the development of certain displacemen ...
of the
mandible
In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla).
The jawbone i ...
are common. However, coronoid process fractures are very rare.
Isolated fractures of the coronoid process caused by direct trauma are rare, as it is anatomically protected by the complex
zygomatic arch
In anatomy, the zygomatic arch (colloquially known as the cheek bone), is a part of the skull formed by the zygomatic process of temporal bone, zygomatic process of the temporal bone (a bone extending forward from the side of the skull, over the ...
/
temporo-zygomatic bone and their associated muscles. Most fractures here are caused by strokes (contusion or penetrating injuries).
of minor fractures can lead to
trismus (lockjaw) that can later only be corrected by removing the coronoid process.
For serious fractures, a
surgery
Surgery is a medical specialty that uses manual and instrumental techniques to diagnose or treat pathological conditions (e.g., trauma, disease, injury, malignancy), to alter bodily functions (e.g., malabsorption created by bariatric surgery s ...
involving
open reduction and internal fixation can have good outcomes.
Additional images
File:Coronoid process of Mandible.gif, Position of coronoid process in skull
The skull, or cranium, is typically a bony enclosure around the brain of a vertebrate. In some fish, and amphibians, the skull is of cartilage. The skull is at the head end of the vertebrate.
In the human, the skull comprises two prominent ...
(shown in red)
File:Coronoid process of Mandible - close-up - animation.gif, Position of coronoid process in mandible
In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla).
The jawbone i ...
(shown in red)
File:Processuscoronoideusmandibulae.PNG, Mandible outer surface (side view; coronoid process labeled at top center)
File:Processuscoronoideusmandibulae2.png, Medial surface
File:Gray382.png, The temporalis, with the zygomatic arch and masseter removed
File:Slide8oooo.JPG, Coronoid process of mandible
File:Slide2cec.JPG, Deep dissection of the mandibular nerve and bone (anterior view)
File:Slide7cece.JPG, Deep dissection of the infratemporal fossa, showing the lingual and inferior alveolar nerve (anterolateral view)
See also
*
Ramus mandibulae
In jawed vertebrates, the mandible (from the Latin ''mandibula'', 'for chewing'), lower jaw, or jawbone is a bone that makes up the lowerand typically more mobilecomponent of the mouth (the upper jaw being known as the maxilla).
The jawbon ...
References
External links
*
* - "Osteology of the Skull: Mandible of Intact Skull"
*
Bones of the head and neck
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