Orbital surface of the body of the maxilla
Encyclopedia
The orbital surface is smooth and triangular, and forms the greater part of the floor of the orbit
.
It is bounded medially by an irregular margin which in front presents a notch, the lacrimal notch; behind this notch the margin articulates with the lacrimal, the lamina papyracea of the ethmoid and the orbital process
of the palatine.
It is bounded behind by a smooth rounded edge which forms the anterior margin of the inferior orbital fissure
, and sometimes articulates at its lateral extremity with the orbital surface of the great wing of the sphenoid.
It is limited in front by part of the circumference of the orbit, which is continuous medially with the frontal process
, and laterally with the zygomatic process
.
Near the middle of the posterior part of the orbital surface is the infraorbital groove
, for the passage of the infraorbital vessels
and nerve
. The groove begins at the middle of the posterior border, where it is continuous with that near the upper edge of the infratemporal surface, and, passing forward, ends in a canal, which subdivides into two branches.
One of the canals, the infraorbital canal
, opens just below the margin of the orbit; the other, which is smaller, runs downward in the substance of the anterior wall of the maxillary sinus, and transmits the anterior superior alveolar vessels and nerve
to the front teeth of the maxilla.
From the back part of the infraorbital canal, a second small canal is sometimes given off; it runs downward in the lateral wall of the sinus
, and conveys the middle alveolar nerve
to the premolar
teeth.
At the medial and forepart of the orbital surface just lateral to the lacrimal groove, is a depression, which gives origin to the Obliquus oculi inferior.
Orbit (anatomy)
In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. "Orbit" can refer to the bony socket, or it can also be used to imply the contents...
.
It is bounded medially by an irregular margin which in front presents a notch, the lacrimal notch; behind this notch the margin articulates with the lacrimal, the lamina papyracea of the ethmoid and the orbital process
Orbital process of palatine bone
The orbital process of the palatine bone is placed on a higher level than the sphenoidal, and is directed upward and lateralward from the front of the vertical part, to which it is connected by a constricted neck. It presents five surfaces, which enclose an air cell...
of the palatine.
It is bounded behind by a smooth rounded edge which forms the anterior margin of the inferior orbital fissure
Inferior orbital fissure
Not to be confused with the infraorbital groove, infraorbital canal, and infraorbital foramen.The lateral wall and the floor of the orbit are separated posteriorly by the inferior orbital fissure which transmits the maxillary nerve and its zygomatic branch, and the ascending branches from the...
, and sometimes articulates at its lateral extremity with the orbital surface of the great wing of the sphenoid.
It is limited in front by part of the circumference of the orbit, which is continuous medially with the frontal process
Frontal process of maxilla
The frontal process of the maxilla is a strong plate, which projects upward, medialward, and backward, by the side of the nose, forming part of its lateral boundary....
, and laterally with the zygomatic process
Zygomatic process of maxilla
The zygomatic process of the maxilla is a rough triangular eminence, situated at the angle of separation of the anterior, zygomatic, and orbital surfaces.* In front it forms part of the anterior surface....
.
Near the middle of the posterior part of the orbital surface is the infraorbital groove
Infraorbital groove
Not to be confused with the inferior orbital fissure, which is just lateral to the infraorbital groove.Also not to be confused with the infraorbital canal, into which the groove enters, nor the infraorbital foramen, which is the canal's opening on the other side.Near the middle of the posterior...
, for the passage of the infraorbital vessels
Infraorbital artery
The infraorbital artery is an artery in the head that runs in the maxilla, emerging through the infraorbital foramen, just under the orbit of the eye.-Course:...
and nerve
Infraorbital nerve
After the maxillary nerve enters the infraorbital canal, the nerve is frequently called the infraorbital nerve. This nerve innervates the lower eyelid, upper lip, and part of the nasal vestibule and exits the infraorbital foramen of the maxilla.-See also:...
. The groove begins at the middle of the posterior border, where it is continuous with that near the upper edge of the infratemporal surface, and, passing forward, ends in a canal, which subdivides into two branches.
One of the canals, the infraorbital canal
Infraorbital canal
Not to be confused with the infraorbital groove and infraorbital foramen, which are on opposite ends of the canal.One of the canals of the orbital surface of the maxilla, the infraorbital canal, opens just below the margin of the orbit...
, opens just below the margin of the orbit; the other, which is smaller, runs downward in the substance of the anterior wall of the maxillary sinus, and transmits the anterior superior alveolar vessels and nerve
Anterior superior alveolar nerve
The anterior superior alveolar branch , of considerable size, is given off from the maxillary nerve just before its exit from the infraorbital foramen; it descends in a canal in the anterior wall of the maxillary sinus, and divides into branches which supply the incisor and canine teeth.It...
to the front teeth of the maxilla.
From the back part of the infraorbital canal, a second small canal is sometimes given off; it runs downward in the lateral wall of the sinus
Maxillary sinus
The pyramid shaped maxillary sinus is the largest of the paranasal sinuses, and drains into the nose. It is present at birth as rudimentary air cells, and develops throughout childhood.-General characteristics:...
, and conveys the middle alveolar nerve
Middle superior alveolar nerve
The middle superior alveolar nerve is a nerve that drops from the infraorbital portion of the maxillary nerve to supply the sinus mucosa, the roots of the maxillary premolars, and the mesiobuccal root of the first maxillary molar....
to the premolar
Premolar
The premolar teeth or bicuspids are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant, making eight premolars total in the mouth. They have at least two cusps. Premolars can be considered as a 'transitional tooth' during chewing, or...
teeth.
At the medial and forepart of the orbital surface just lateral to the lacrimal groove, is a depression, which gives origin to the Obliquus oculi inferior.