Frontal bone
| ((((Frontal bone)))) | |
|---|---|
 Frontal bone highlighted in red | |
| Details | |
| Articulations | twelve bones: the sphenoid, the ethmoid, the two parietals, the two nasals, the two maxillæ, the two lacrimals, and the two zygomatics |
| Identifiers | |
| Latin | os frontale |
| MeSH | D005624 |
| TA98 | A02.1.03.001 |
| TA2 | 520 |
| FMA | 52734 |
| Anatomical terms of bone | |
The frontal bone or os frontis is a bone in the human skull. The name comes from the Latin word frons (meaning "forehead"). The bone resembles a cockleshell in form, and consists of three portions:[1]
- a large vertical portion, the squama frontalis, corresponding with the region of the forehead.
- an orbital or horizontal portion, the pars orbitalis, which enters into the formation of the roofs of the orbital and nasal cavities.
- a nasal portion, it articulates with the nasal bones and the frontal process of the maxilla to form the root of the nose.
Embryology
The frontal bone is presumed to be derived from neural crest cells.[2]
Borders
The border of the squama frontalis is thick, strongly serrated, bevelled at the expense of the inner table above, where it rests upon the parietal bones, and at the expense of the outer table on either side, where it receives the lateral pressure of those bones; this border is continued below into a triangular, rough surface, which articulates with the great wing of the sphenoid. The posterior borders of the orbital plates are thin and serrated, and articulate with the small wings of the sphenoid. [1]
In other animals
In most vertebrates, the frontal bone is paired, rather than presenting the single, fused structure found in humans. It typically lies on the upper part of the head, between the eyes, but in many non-mammalian animals it does not form part of the orbital cavity. Instead, in reptiles, bony fish and amphibians it is often separated from the orbits by one or two additional bones not found in mammals. These bones, the prefrontals and postfrontals, together form the upper margin of the eye sockets, and lie to either side of the frontal bones.[3]
See also
References
- ^ a b Gray's Anatomy (1918). (See infobox)
- ^ Kirby, ML; Waldo, KL. Circulation (1990) 82:332-340.
- ^ Romer, Alfred Sherwood; Parsons, Thomas S. (1977). The Vertebrate Body. Philadelphia, PA: Holt-Saunders International. pp. 226–241. ISBN 0-03-910284-X.
This article incorporates text in the public domain from page 135 of the 20th edition of Gray's Anatomy (1918)
Additional Images
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Frontal bone at newborn -
Frontal bone orbital part
External links
- Anatomy photo:23:os-0101 at the SUNY Downstate Medical Center
- Template:RocheLexicon