jaw

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jaw

 [jaw]
either the mandible (lower jaw) or the maxilla (upper jaw), two opposing bony structures of the mouth of a vertebrate; they bear the teeth and are used for seizing prey, for biting, or for masticating food. See anatomic Table of Bones in the Appendices.
cleft jaw a cleft between the median nasal and maxillary processes through the alveolus; see also cleft palate. Called also gnathoschisis.
Hapsburg jaw a mandible that is prognathous, often accompanied by Hapsburg lip. See illustration.
Hapsburg jaw with Hapsburg lip.
phossy jaw phosphonecrosis.

jaw

(jaw),
1. One of the two bony structures in which the teeth are set to form the framework of the mouth.
2. Common name for either the maxillae or the mandible.
[A.S. ceōwan, to chew]

jaw

(jaw) either of the two bony tooth-bearing structures (mandible and maxilla) in the head of dentate vertebrates.
cleft jaw  a cleft between the median nasal and maxillary prominences through the alveolus.
Hapsburg jaw  a mandibular prognathous jaw, often accompanied by Hapsburg lip.
phossy jaw  phosphorus necrosis.

jaw

(jô)
n.
a. Either of two bony or cartilaginous structures that in most vertebrates form the framework of the mouth and hold the teeth.
b. The mandible or maxilla or the part of the face covering these bones.
c. Any of various structures of invertebrates that have an analogous function to vertebrate jaws.

jaw′less adj.

jaw

Etymology: AS, ceowan, to chew
a common term used to describe the maxillae and the mandible and the soft tissue that covers these structures, which contain the teeth and form the framework for the mouth. See also jaw relation.

jaw

(jaw)
1. One of the two bony structures, in which the teeth are set, forming the framework of the mouth.
2. Common name for either the maxilla or the mandible.
[A.S. ceōwan, to chew]

jaw

(jo)
Enlarge picture
JAW
1. Either or both of the maxillary and mandibular bones, bearing the teeth and forming the mouth framework. See: illustration
2. The grasping part of a surgical instrument. The word is usually used in the plural.

cleft jaw

An early embryonic malformation resulting in lack of fusion of the right and left mandible into a single bone.

crackling jaw

Noise in the normal or diseased temporomandibular joint during movement of the jaw. Synonym: crepitation

lumpy jaw

Actinomycosis.

jaw

1. The mandible, the U-shaped bone that articulates with the base of the skull high up in front of the ears. In biting and chewing (mastication) the mandible is pulled upwards by powerful muscles running down from the base and temples (temporal bones) of the skull.
2. The MAXILLA, or upper jaw.

jaw

the mandibles of any animal. The term is usually restricted to the bones surrounding the mouth of vertebrates, the (paired) upper jaws being referred to as the maxillae and the lower as the mandible. These bones carry the teeth where present, and are often used for crushing purposes.

jaw

(jaw)
1. One of the two bony structures in which teeth are set to form oral framework.
2. Common name for either maxillae or mandible.
[A.S. ceōwan, to chew]

jaw

either of the two opposing bony structures (maxilla and mandible) of the mouth of vertebrates; they bear the teeth and are used for seizing prey, for biting, or for masticating food.

jaw bone
the mandible or maxilla, especially the mandible.
jaw champing
involuntary, rapid, repetitive clenching of the teeth; accompanied by frothing of saliva; frequently accompanies clonic convulsions.
jaw chattering
involuntary, rapid clicking together of the teeth without salivation and usually accompanied by generalized shivering; in animals, may be a sign of painful teeth.
dropped jaw
see mandibular neurapraxia.
jaw locking
a dislocation of the jaw, usually following wide opening, in which the mouth cannot be closed. See also temporomandibular dysplasia.
jaw malapposition
overshot jaw
pig jaw
jaw retractor
a dental gag used to keep the jaws of an animal as open as possible.
rubber jaw
see renal secondary hyperparathyroidism.
undershot jaw

Patient discussion about jaw

Q. after dinner my daughters jaw swelled up on one side and hurts her, so does her neck on that side. What does this mean? she is 9, no fever or any other ill effects, just the pain

A. weird. swelled up fast? does she have problem breathing? if so- it could be an allergic reaction. if she has problems breathing - GO NOW TO AN ER!!!
if it took a little bit - could be food that got stuck in her gums really hard causing an edema.
if it was slow (over night) could be an abscess in her tooth (a tooth decay that penetrated to the dental pulp).
any way i would go check it out.

More discussions about jaw
References in periodicals archive ?
By imaging the internal structure of the skull using high-energy X-rays at the European Synchrotron (ESRF) in Grenoble, France, the authors show that the skull housed a brain with a short front end, very similar to that of a jawless vertebrate.
Hox cluster organization in the jawless vertebrate Petromyzon marinus.
Another aim is to protect river lampreys, a primitive kind of jawless fish.
Cute it's not, but the lamprey - a jawless fish of ancient origin - deserves protection under the federal Endangered Species Act, said a dozen West Coast conservation groups in a lawsuit they filed Wednesday.
Scientists know little about the emergence of these sophisticated immune systems about 500 million years ago, which occurred as vertebrates evolved from jawless into jawed creatures.
This new revision of the lineage of early jawed vertebrates will allow paleontologists to dig into deeper mysteries, including how the body plan of these ancient species transformed over the transition from jawless to jawed fishes.
Diversity and function of adaptive immune receptors in a jawless vertebrate.
Lampreys are modern, jawless descendants of those early fishes.
Numerous jawless fishes characteristic of the Siberian Early Devonian, amphiaspidids, come mostly from the Siberian Platform, also from the adjacent Tajmyr Peninsula.
Now, an international team of researchers, led by a faculty member from the University of Colorado, has noted that three genes in jawless vertebrates might have been key to the development of jaws in higher vertebrates.