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Gwenocracy
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The ‘ maxilla ’ is the term used to define the upper jaw, which in fact is made up of the two maxillae, each consisting of a body and four processes . The body is roughly pyramidal in shape
Its interior is hollowed out by the maxillary paranasal air sinus , alternatively termed the maxillary antrum . The upper (orbital) surface of the body occupies the floor of the orbit; the posterior surface provides the anterior wall of the infratemporal fossa, the medial surface is a major structural component in the wall of the nasal cavity and the anterior surface forms the curved external surface of the upper jaw .
Above the incisor teeth the anterior surface has a shallow depression termed the incisive fossa . Lateral to this is a ridge termed the canine eminence , formed by the root of the canine tooth, which separates the incisive fossa from the further lateral and deeper canine fossa . Above the canine fossa is the infraorbital foramen . The anterior surface ends medially at the pear - shaped piriform (anterior nasal) aperture, inferior to which the maxillae form a median projection, the anterior nasal spine .
The four maxillary processes are:
• The zygomatic process : This projects laterally from the
body, forming the anterior part of the zygomatic arch.
• The frontal process : This projects upwards to articulate with
the frontal bone, and forms the lateral wall of the nose, articulating medially with the nasal bone .
• The palatine process : Th s projects medially to articulate
with that of the opposite side, together forming the anterior
three - quarters of the bony palate ; the posterior one - quarter
is formed by the horizontal plates of the palatine bones. The
bony palate provides the roof of the oral cavity and the floor
of the nasal cavity. The right and left sides of the bony palate
are separated by the median suture .
The posterior border of the bony palate has a median projection, termed the posterior nasal spine .
The bony palate, together with its covering
mucous membrane, is termed the hard palate .
The hard palate is arched more by the downward projecting alveolar
processes of the maxillae than by any upward concavity of
the palatine processes.
• The alveolar process : This projects downwards, forming the alveoli (sockets) for the roots of the maxillary teeth. The
alveolar process ends posteriorly at the maxillary tuberosity , a prominent rounded eminence located behind the last
molar tooth.
Its interior is hollowed out by the maxillary paranasal air sinus , alternatively termed the maxillary antrum . The upper (orbital) surface of the body occupies the floor of the orbit; the posterior surface provides the anterior wall of the infratemporal fossa, the medial surface is a major structural component in the wall of the nasal cavity and the anterior surface forms the curved external surface of the upper jaw .
Above the incisor teeth the anterior surface has a shallow depression termed the incisive fossa . Lateral to this is a ridge termed the canine eminence , formed by the root of the canine tooth, which separates the incisive fossa from the further lateral and deeper canine fossa . Above the canine fossa is the infraorbital foramen . The anterior surface ends medially at the pear - shaped piriform (anterior nasal) aperture, inferior to which the maxillae form a median projection, the anterior nasal spine .
The four maxillary processes are:
• The zygomatic process : This projects laterally from the
body, forming the anterior part of the zygomatic arch.
• The frontal process : This projects upwards to articulate with
the frontal bone, and forms the lateral wall of the nose, articulating medially with the nasal bone .
• The palatine process : Th s projects medially to articulate
with that of the opposite side, together forming the anterior
three - quarters of the bony palate ; the posterior one - quarter
is formed by the horizontal plates of the palatine bones. The
bony palate provides the roof of the oral cavity and the floor
of the nasal cavity. The right and left sides of the bony palate
are separated by the median suture .
The posterior border of the bony palate has a median projection, termed the posterior nasal spine .
The bony palate, together with its covering
mucous membrane, is termed the hard palate .
The hard palate is arched more by the downward projecting alveolar
processes of the maxillae than by any upward concavity of
the palatine processes.
• The alveolar process : This projects downwards, forming the alveoli (sockets) for the roots of the maxillary teeth. The
alveolar process ends posteriorly at the maxillary tuberosity , a prominent rounded eminence located behind the last
molar tooth.
