Maxillae

The maxillae are a pair of irregular bones that form the upper jaw and constitute a central part of the facial skeleton. Each maxilla contributes to the floor of the orbit, the lateral wall of the nasal cavity, and the anterior portion of the hard palate. They also host the upper dentition in the alveolar process, where the dental sockets (alveoli) accommodate the teeth.

Anatomically, each maxilla has a body containing the maxillary sinus, and several processes. The frontal process projects upward to meet the frontal bone, the zygomatic process extends laterally to articulate with the zygomatic bone, and the palatine process joins with the horizontal plates of the palatine bones to form most of the hard palate. The infraorbital foramen on the facial surface transmits the infraorbital nerve and vessels. The maxilla articulates with numerous bones, including the nasal, lacrimal, inferior nasal concha, ethmoid, palatine, vomer, zygomatic, frontal, and sphenoid bones.

Developmentally, the maxilla arises from the maxillary prominence of the first pharyngeal (branchial) arch and forms by intramembranous ossification. The maxillary sinus, one of the paranasal sinuses, lies within the body and can affect voice resonance and sinus health.

Clinically, the maxillae are central to dental function and facial structure. They can be involved in injuries such as Le Fort fractures, and provide the bone bed for dental implants and various reconstructive procedures.