Body of maxilla

Structure and surfaces of the body of the maxilla

The body of the maxilla has four surfaces:

• Orbital surface (Facies orbitalis) forms the inferior wall of the orbit. It features the infraorbital groove (Sulcus infraorbitalis), which continues into the infraorbital canal (Canalis infraorbitalis). This canal opens on the face via the infraorbital foramen (Foramen infraorbitale), the exit of which is located in the region of the canine fossa (Fossa canina).
• Anterior surface (Facies anterior) is bounded superiorly by the infraorbital margin (Margo infraorbitalis). Medially, it transitions into the nasal notch (Incisura nasalis), and inferiorly, near the anterior margin, lies the anterior nasal spine (Spina nasalis anterior).
• Infratemporal surface (Facies infratemporalis) is almost entirely occupied by the maxillary tuberosity (Tuber maxillae, or Eminentia maxillae). The tuberosity features alveolar foramina (Foramina alveolaria), which lead into alveolar canals (Canales alveolares). Vessels and nerves pass through these canals to the roots of the premolars and molars.
• Nasal surface (Facies nasalis) is bounded anteriorly by the lacrimal groove (Sulcus lacrimalis), which runs along the border with the frontal process. The surface features a wide maxillary hiatus (Hiatus maxillaris), which is the opening into the maxillary sinus. Posteriorly, along the border with the palatine bone, runs the greater palatine groove (Sulcus palatinus major), which, together with the corresponding groove of the palatine bone, forms the greater palatine canal.

What is located inside the body?

The maxillary sinus (Sinus maxillaris) is located within the spongy substance of the body of the maxilla. This air-containing cavity communicates with surrounding structures via the maxillary hiatus on the nasal surface. On the intact skull, this entrance is partially covered by the middle nasal concha and adjacent bone elements.

Topography and connections with adjacent structures

The body of the maxilla has four processes: the frontal (Processus frontalis), zygomatic (Processus zygomaticus), alveolar (Processus alveolaris), and palatine (Processus palatinus). Inferiorly, the body of the maxilla forms the boundary of the ethmoidal labyrinth (Labyrinthus ethmoidalis).

Clinical significance and traumatology

The severity of facial injuries is directly proportional to the angle of inclination of the wound tract relative to the horizontal plane. Injuries to the body of the maxilla and the maxillary sinus occur in 30% of gunshot fractures of the upper jaw.

The wound tract may be interrupted in nature. In case of trauma, marked asymmetry is possible: the body of the maxilla may be injured on one side, while the hard palate, alveolar process, or tissues of the floor of the oral cavity are affected on the opposite side. Additional destruction of the body of the jaw and sinus walls can be caused by secondary missiles—bone fragments and teeth from the damaged alveolar process.

Surgical management: If the wound tract passes through the body of the maxilla, exploration of the maxillary sinus, nasal meatuses, and ethmoidal labyrinth is mandatory.

• In extensive wounds, blood clots, foreign bodies, and bone fragments are removed, and altered mucous membrane is excised. Viable mucosa is preserved, repositioned onto the bone framework, and packed with an iodoform gauze.
• A mandatory step is the creation of an artificial anastomosis with the inferior nasal meatus, through which the end of the gauze pack is brought out.
• If the entry wound is small, exploration is performed from the oral vestibule using the classic Caldwell-Luc antrostomy approach.

Class and exam questions

What else to study on this topic

• Maxillary Sinus (Sinus maxillaris)
• Processes of the Maxilla
• Ethmoidal Labyrinth (Labyrinthus ethmoidalis)
• Gunshot Fractures of the Facial Bones

Other topics in the "Anatomical Structures" section

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.