MAXILLARY BONE, SUPERIOR
\mˈaksɪləɹi bˈə͡ʊn], \mˈaksɪləɹi bˈəʊn], \m_ˈa_k_s_ɪ_l_ə_ɹ_i b_ˈəʊ_n]\
Sort: Oldest first
-
The upper jaw-bones are to the face what the sphenoid bone is to the cranium. They are articulated with all the portions composing it. They determine, almost alone, the shape of the face, and give it solidity. Their size is considerable; form unequal. They occupy the middle and anterior part of the face; and enter into the composition of the nsal fossae, orbit, and mouth. The chief parts observable in the upper jaw are- 1. Externally, the Nasal process which forms almost the entire floor of the orbit. 2. Internally, its circumference is very unequal, and it has behind a round, unequal prominence, called the Maxillary tuberosity, which is pierced by the posterior dental canal. Anteriorly, there is a notch, which forms part of the anterior aperture of the nasal fossae, and beneath, an eminence, called the anterior nasal spine. The lower part of this circumference forms the alveolar margin. Each superior maxillary bone is articulated with the ethmoid, frontal, nasal, lachrymal, palatine, inferior spongy, vomer, its fellow, the teeth of the upper jaw, and sometimes the sphenoid bone. It is developed by four or five points of ossification.
By Robley Dunglison
Word of the day
SQ10,643
- A serotonin antagonist with limited antihistaminic, anticholinergic, and immunosuppressive activity.