Maxilla
The maxillae (plural: maxillae ) are the two maxilla bones forming the upper jaw and palate of the mouth. The two halves are fused at the intermaxillary suture to form the upper jaw. This is similar to the mandible (lower jaw), which is also a fusion of two halves at the mandibular symphysis.
Sometimes (e.g. in bony fish), the maxilla is called "upper maxilla," with the mandible being the "lower maxilla." Conversely, in birds the upper jaw is often called "upper mandible."
Structure
Each half of the fused maxillae consists of:
The body of the maxilla
Four processes
The zygomatic process
The frontal process of maxilla
The alveolar process
The palatine process
Infraorbital foramen
The maxillary sinus
Articulations
Each maxilla articulates with nine bones:
two of the cranium: the frontal and ethmoid
seven of the face: the nasal, zygomatic, lacrimal, inferior nasal concha, palatine, vomer, and the adjacent fused maxilla.
