iPedia Free Information Center

Information about Ramus Mandibulae

Bone: Ramus of the mandible
Mandible. Outer surface. Side view
Mandible. Inner surface. Side view
Latinramus mandibulae
subject #44 173
Dorlands/Elsevier r_02/12690707
The ramus of the mandible (perpendicular portion) is quadrilateral in shape, and has two surfaces, four borders, and two processes.

Surfaces

The lateral surface is flat and marked by oblique ridges at its lower part; it gives attachment throughout nearly the whole of its extent to the masseter.

The medial surface presents about its center the oblique mandibular foramen, for the entrance of the inferior alveolar vessels and nerve.

The margin of this opening is irregular; it presents in front a prominent ridge, surmounted by a sharp spine, the lingula mandibulae, which gives attachment to the sphenomandibular ligament; at its lower and back part is a notch from which the mylohyoid groove runs obliquely downward and forward, and lodges the mylohyoid vessels and nerve.

Behind this groove is a rough surface, for the insertion of the internal pterygoid muscle (Pterygoideus internus). The mandibular canal runs obliquely downward and forward in the ramus, and then horizontally forward in the body, where it is placed under the alveoli and communicates with them by small openings.

On arriving at the incisor teeth, it turns back to communicate with the mental foramen, giving off two small canals which run to the cavities containing the incisor teeth.

In the posterior two-thirds of the bone the canal is situated nearer the internal surface of the mandible; and in the anterior third, nearer its external surface.

It contains the inferior alveolar vessels and nerve, from which branches are distributed to the teeth.

Borders

The lower border of the ramus is thick, straight, and continuous with the inferior border of the body of the bone. At its junction with the posterior border is the angle of the mandible, which may be either inverted or everted and is marked by rough, oblique ridges on each side, for the attachment of the Masseter laterally, and the Pterygoideus internus medially; the stylomandibular ligament is attached to the angle between these muscles. The anterior border is thin above, thicker below, and continuous with the oblique line.

The posterior border is thick, smooth, rounded, and covered by the parotid gland. The upper border is thin, and is surmounted by two processes, the coronoid in front and the condyloid behind, separated by a deep concavity, the mandibular notch.

Processes

The coronoid process is a thin, triangular eminence, which is flattened from side to side and varies in shape and size.

The condyloid process is thicker than the coronoid, and consists of two portions: the condyle, and the constricted portion which supports it, the neck.

The mandibular notch, separating the two processes, is a deep semilunar depression, and is crossed by the masseteric vessels and nerve.

Additional images


The skull from the front.

The Temporalis; the zygomatic arch and Masseter have been removed.

The Pterygoidei; the zygomatic arch and a portion of the ramus of the mandible have been removed.


External links

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.
 •  • [ e]
Bones of head and neck: the face
maxillaBody of maxilla - Maxillary sinus - surfaces of body Anterior (Incisive fossa, Canine fossa, Infraorbital foramen, Anterior nasal spine) - Infratemporal (Alveolar canals, Maxillary tuberosity) - Orbital (Infraorbital groove, Infraorbital canal) - Nasal (Pterygopalatine canal) - processes Zygomatic process - Frontal process (Agger nasi, Anterior lacrimal crest) - Alveolar process - Palatine process (Incisive foramen, Incisive canals, Foramina of Scarpa, Premaxilla, Anterior nasal spine)
lacrimalPosterior lacrimal crest - Lacrimal groove
zygomaticOrbital process, Zygomaticofacial foramen - Zygomaticotemporal foramen - Zygomaticorbital foramina
palatinePterygopalatine fossa - Pterygoid fossa - Horizontal plate (Posterior nasal spine) - Perpendicular plate (Pterygopalatine canal, Sphenopalatine foramen, Pyramidal process)
processes (Orbital - Sphenoidal)
mandiblebody (Symphysis menti, Mental protuberance, Mental foramen, Mylohyoid line) - Ramus (Mandibular foramen, Mylohyoid groove, Mandibular canal, Angle, Coronoid process, Condyloid process, Mandibular notch)
othersnasal bone - inferior nasal conchae (ethmoidal process, maxillary process) - vomer
mandible (from Latin mandibūla, "jawbone") or inferior maxillary bone is, together with the maxilla, the largest and strongest bone of the face . It forms the lower jaw and holds the lower teeth in place.
..... Click the link for more information.
Latin}}} 
Official status
Official language of: Vatican City
Used for official purposes, but not spoken in everyday speech
Regulated by: Opus Fundatum Latinitas
Roman Catholic Church
Language codes
ISO 639-1: la
ISO 639-2: lat
..... Click the link for more information.
Elsevier, the world's largest publisher of medical and scientific literature, forms part of the Reed Elsevier group. Based in Amsterdam, the company has substantial operations in the UK, USA and elsewhere.
..... Click the link for more information.
mandible (from Latin mandibūla, "jawbone") or inferior maxillary bone is, together with the maxilla, the largest and strongest bone of the face . It forms the lower jaw and holds the lower teeth in place.
..... Click the link for more information.
quadrilateral is a polygon with four sides or edges and four vertices or corners. Sometimes, the term quadrangle is used, for etymological symmetry with triangle, and sometimes tetragon
..... Click the link for more information.
Shape (OE. sceap Eng. created thing), refers to the external two-dimensional outline, appearance or configuration of some thing — in contrast to the matter or content or substance of which it is composed.
..... Click the link for more information.
In human anatomy, the masseter is one of the muscles of mastication.

It is particularly powerful in herbivores to assist when they are chewing plants.

Origin and insertion of the two heads


..... Click the link for more information.
The Mandibular foramen is an opening on the internal surface of the ramus (posterior and perpendicularly oriented part of the mandible) for divisions of the mandibular vessels and nerve to pass.
..... Click the link for more information.
The inferior alveolar artery (inferior dental artery) is an artery of the face.

Course

It descends with the inferior alveolar nerve to the mandibular foramen on the medial surface of the ramus of the mandible.
..... Click the link for more information.
The inferior alveolar nerve (sometimes called the inferior dental nerve) is a branch of the mandibular nerve, which is itself the third branch (V3) of the fifth cranial nerve, the trigeminal nerve (cranial nerve V).
..... Click the link for more information.
mylohyoid groove runs obliquely downward and forward, and lodges the mylohyoid vessels and nerve.

Behind this groove is a rough surface, for the insertion of the Pterygoideus internus.
..... Click the link for more information.
As the inferior alveolar artery enters the mental foramen, it gives off a mylohyoid branch which runs in the mylohyoid groove, and ramifies on the under surface of the Mylohyoideus.
..... Click the link for more information.
The medial pterygoid (or internal pterygoid muscle), is a thick, quadrilateral muscle of mastication.

The mandibular branch of the fifth cranial nerve, the trigeminal nerve, innervates the medial pterygoid muscle.
..... Click the link for more information.
The introduction to this article provides insufficient context for those unfamiliar with the subject matter.
Please help [ improve the introduction] to meet Wikipedia's layout standards.

..... Click the link for more information.
The mental foramen is one of two holes ("foramina") located on the anterior surface of the mandible. It permits passage of the mental nerve and vessels. The mental foramen descends slightly in edentulous individuals[1].
..... Click the link for more information.
The medial pterygoid (or internal pterygoid muscle), is a thick, quadrilateral muscle of mastication.

The mandibular branch of the fifth cranial nerve, the trigeminal nerve, innervates the medial pterygoid muscle.
..... Click the link for more information.
The stylomandibular ligament is a specialized band of the cervical fascia, which extends from near the apex of the styloid process of the temporal bone to the angle and posterior border of the angle of the mandible, between the Masseter and Pterygoideus internus.
..... Click the link for more information.
For the toad wart, see parotoid gland.

The parotid gland is the largest of the salivary glands. It is found wrapped around the mandibular ramus, and it secretes saliva through Stensen's duct into the oral cavity, to facilitate mastication and swallowing.
..... Click the link for more information.
The Coronoid process (from Greek korone, "like a crow's beak") can refer to:
  • The coronoid process of the mandible, part of the ramus mandibulae of the mandible
  • The coronoid process of the ulna

..... Click the link for more information.
The condyloid process is thicker than the coronoid, and consists of two portions: the condyle, and the constricted portion which supports it, the neck.

Condyle

The condyle presents an articular surface for articulation with the articular disk of the temporomandibular
..... Click the link for more information.
Masseteric can refer to:
  • Masseteric artery
  • Masseteric nerve
  • Masseter muscle

..... Click the link for more information.
Georgetown University is a private, Jesuit, research university, located in Washington, D.C.'s Georgetown neighborhood. Father John Carroll founded the school in 1789, though its roots extend back to 1634.
..... Click the link for more information.
Elsevier, the world's largest publisher of medical and scientific literature, forms part of the Reed Elsevier group. Based in Amsterdam, the company has substantial operations in the UK, USA and elsewhere.
..... Click the link for more information.
The Pennsylvania State University (commonly known as Penn State) is a state-related, land-grant university. The University has 24 campuses throughout the U.S. state of Pennsylvania, including a virtual World Campus.
..... Click the link for more information.
Elsevier, the world's largest publisher of medical and scientific literature, forms part of the Reed Elsevier group. Based in Amsterdam, the company has substantial operations in the UK, USA and elsewhere.
..... Click the link for more information.
Public domain comprises the body of knowledge and innovation (especially creative works such as writing, art, music, and inventions) in relation to which no person or other legal entity can establish or maintain proprietary interests within a particular legal jurisdiction.
..... Click the link for more information.
Henry Gray's Anatomy of the Human Body (or Gray's Anatomy as it has commonly been shortened) is an English-language human anatomy textbook widely regarded as a classic work on the subject.
..... Click the link for more information.
Bones are rigid organs that form part of the endoskeleton of vertebrates. They function to move, support, and protect the various organs of the body, produce red and white blood cells and store minerals.
..... Click the link for more information.
Head and neck anatomy focuses on the structures of the head and neck of the human body, including the brain, bones, muscles, blood vessels, nerves, glands, nose, mouth, teeth, tongue, and throat.
..... Click the link for more information.
The face is the front part of the head, in humans from the forehead to chin including the hair, forehead, eyebrow, eyes, nose, cheeks, mouth, lips, philtrum, teeth, skin, and chin. The face is used for expression, appearance and identity amongst others.
..... Click the link for more information.


This article is copied from an article on Wikipedia.org - the free encyclopedia created and edited by online user community. The text was not checked or edited by anyone on our staff. Although the vast majority of the wikipedia encyclopedia articles provide accurate and timely information please do not assume the accuracy of any particular article. This article is distributed under the terms of GNU Free Documentation License.
Herod_Archelaus


page counter