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 Eminence may refer to: Places in the United States * Eminence, Arkansas, List of places in Arkansas: E, a place in Arkansas * Eminence, Indiana * Eminence, Kansas * Eminence, Kentucky * Eminence, Mississippi, in Covington County, Mississippi * Em ...

, 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 mandibular notch, also known as the sigmoid notch, is a groove in the ramus of the mandible. It is the gap between the coronoid process anteriorly and the condyloid process posteriorly. Structure The mandibular notch is a concave groove at ...

. The ''lateral surface'' is smooth, and affords insertion to the

temporalis In anatomy, the temporalis muscle, also known as the temporal muscle, is one of the muscles of mastication (chewing). It is a broad, fan-shaped convergent muscle on each side of the head that fills the temporal fossa, superior to the zygomatic ...

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 The bucinator () is a thin quadrilateral muscle occupying the interval between the maxilla and the mandible at the side of the face. It forms the anterior part of the cheek or the lateral wall of the oral cavity.Illustrated Anatomy of the Head an ...

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

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).

Conservative management Conservative treatment is a type of medical treatment defined by the avoidance of invasive measures such as surgery or other invasive procedures, usually with the intent to preserve function or body parts. For example, in appendicitis, conservati ...

of minor fractures can lead to

trismus Trismus is a condition of restricted opening of the mouth. The term was initially used in the setting of tetanus. Trismus may be caused by spasm of the muscles of mastication or a variety of other causes. Temporary trismus occurs much more freque ...

(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 Internal fixation is an operation in orthopedics that involves the surgical implementation of implants for the purpose of repairing a bone, a concept that dates to the mid-nineteenth century and was made applicable for routine treatment in the ...

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

(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)

References

External links

* * - "Osteology of the Skull: Mandible of Intact Skull" * Bones of the head and neck {{musculoskeletal-stub

Clinical significance

Additional images

See also

References

External links