Frontal bone
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| Bone: Frontal bone | ||
|---|---|---|
| Frontal bone at birth. | ||
| Latin | os frontale | |
| Gray's | subject #33 135 | |
| Articulations | twelve bones: the sphenoid, the ethmoid, the two parietals, the two nasals, the two maxillæ, the two lacrimals, and the two zygomatics | |
| MeSH | Frontal+Bone | |
The frontal bone is a bone in the human skull that resembles a cockleshell in form, and consists of two portions:
- a 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.
Contents |
[edit] 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.
[edit] Structure
The squama and the zygomatic processes are very thick, consisting of diploic tissue contained between two compact laminæ; the diploic tissue is absent in the regions occupied by the frontal air sinuses.
The orbital portion is thin, translucent, and composed entirely of compact bone; hence the facility with which instruments can penetrate the cranium through this part of the orbit; when the frontal sinuses are exceptionally large they may extend backward for a considerable distance into the orbital portion, which in such cases also consists of only two tables.
[edit] Additional images
Orbital bones.png
The seven bones which articulate to form the orbit. |
Illu facial bones.jpg
Facial bones. |
Illu cranial bones.jpg
Cranial bones |
Gray164.png
Sphenoid bone visible center right. |
Gray188.png
Side view of the skull. |
Gray189.png
|
Gray190.png
The skull from the front. |
Gray192.png
Medial wall of left orbit. |
Gray193.png
Floor of the skull. |
Gray194.png
Sagittal section of skull. |
[edit] See also
[edit] 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 As such, some of the information contained herein may be outdated.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.
The Bones which form the Orbit | |
|---|---|
| Frontal bone • Zygomatic bone • Maxillary bone • Sphenoid bone • Ethmoid bone • Palatine bone • Lacrimal bone | Image:Orbital bones.png |
de:Stirnbein es:Hueso frontal fr:Os frontal gl:Frontal (óso) ko:이마뼈 it:Osso frontale la:Os frontale lv:Pieres kauls lt:Kaktikaulis ja:前頭骨 pl:Kość czołowa pt:Osso frontal ru:Лобная кость sl:Čelnica sv:Pannben tr:Os frontale uk:Лобова кістка zh:额骨
