In human anatomy, the
mandible
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 ...
's coronoid process (from Greek ''korōnē'', denoting something hooked) 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 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 ...
. The ''lateral surface'' is smooth, and affords insertion to the
temporalis and
masseter
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 ...
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.
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 separation of an object or material into two or more pieces under the action of stress. The fracture of a solid usually occurs due to the development of certain displacement discontinuity surfaces within the solid. If a displ ...
of the
mandible
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 ...
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, 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 zygo ...
/
temporo-zygomatic bone and their associated muscles. Most fractures here are caused by strokes (contusion or penetrating injuries).
Conservative management Conservative management 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 (lockjaw) that can later only be corrected by removing the coronoid process.
For serious fractures, a
surgery
Surgery ''cheirourgikē'' (composed of χείρ, "hand", and ἔργον, "work"), via la, chirurgiae, meaning "hand work". is a medical specialty that uses operative manual and instrumental techniques on a person to investigate or treat a pa ...
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 is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, th ...
(shown in red)
File:Coronoid process of Mandible - close-up - animation.gif, Position of coronoid process in mandible
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 ...
(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 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 ...
References
External links
*
* - "Osteology of the Skull: Mandible of Intact Skull"
*
Bones of the head and neck
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