Other Definitions
nasal bone (dict)
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Nasal BoneThe nasal bones (ossa faciei & ossa nasalia) are two small oblong bones, varying in size and form in different individuals; they are placed side by side at the middle and upper part of the face, and form, by their junction, "the bridge" of the nose. Each has two surfaces and four borders. Surfaces The outer surface (Fig. 2) is concavoconvex from above downward, convex from side to side; it is covered by the Procerus and Compressor naris, and perforated about its center by a foramen, for the transmission of a small vein. The inner surface (Fig. 3) is concave from side to side, and is traversed from above downward, by a groove for the passage of a branch of the nasociliary nerve. Borders The superior border is narrow, thick, and serrated for articulation with the nasal notch of the frontal bone. The inferior border is thin, and gives attachment to the lateral cartilage of the nose; near its middle is a notch which marks the end of the groove just referred to. The lateral border is serrated, bevelled at the expense of the inner surface above, and of the outer below, to articulate with the frontal process of the maxilla. The medial border, thicker above than below, articulates with its fellow of the opposite side, and is prolonged behind into a vertical crest, which forms part of the nasal septum: this crest articulates, from above downward, with the spine of the frontal, the perpendicular plate of the ethmoid, and the septal cartilage of the nose.
Figure 1 : Articulation of nasal and lacrimal bones with maxilla.
Figure 2 : Right nasal bone. Outer surface. |
Figure 3 : Right nasal bone. Inner surface. |
Ossification Each bone is ossified from one center, which appears at the beginning of the third month of fetal life in the membrane overlying the front part of the cartilaginous nasal capsule. Articulations The nasal articulates with four bones: two of the cranium, the frontal and ethmoid, and two of the face, the opposite nasal and the maxilla. This article is based on an entry from the 1918 edition of Gray's Anatomy, which is in the public domain. As such, some of the information contained herein may be outdated.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. See also
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