Maxilla: Location, Anatomy, Functions, and Clinical Importance
Run a finger along the bony ridge just beneath your eyes and above your upper teeth – that ridge belongs to the Midface bone, one of the most structurally important bones in the human skull. It does far more than anchor your teeth: the Midface bone articulates with nine other skull bones, making it the central connector of the entire midface.
The Midface bone is a paired facial bone that forms the upper jaw and contributes to the floor of the orbit, the lateral wall and floor of the nasal cavity, the hard palate, and the upper dental arch. It consists of a body and four processes – frontal, zygomatic, palatine, and alveolar – and links to nine surrounding bones. This guide walks through its full anatomy, from surface landmarks to nerve supply, and explains what happens clinically when the Midface bone is fractured, infected, or surgically repositioned.
Where Is the Midface Bone Located?
The Midface bone sits in the middle third of the face, forming the upper jaw between the nose and the mouth. It is a paired bone – the left and right midface bones meet at a midline suture – and together they border three separate cavities at once: the mouth below, the nasal cavity medially, and the orbit above.
No other facial bone touches this many major cavities simultaneously, which is a major reason it plays such a central structural role in the skull.
Parts of the Midface bone: Body and Processes
The Midface bone is built around a hollow, pyramid-shaped body with four surfaces, plus four bony processes projecting outward from it.
Surfaces of the Midface bone: Body
| Surface | Faces Toward | Notable Landmarks |
| Facial (anterior) | Front of the face | Infraorbital foramen, canine fossa, canine eminence, incisive fossa |
| Infratemporal (posterior) | Infratemporal fossa | Midface bony tuberosity, posterior superior alveolar foramina |
| Orbital (superior) | Eye socket | Infraorbital groove and canal, forms most of the orbital floor |
| Nasal (medial) | Nasal cavity | Midface bony hiatus, nasal notch, anterior nasal spine |
Key Surface Landmarks Worth Knowing
- Canine fossa and canine eminence – a shallow depression and adjacent ridge on the facial surface, corresponding to the canine tooth root
- Incisive fossa – a small depression above the incisor teeth
- Midface bony tuberosity – a rounded prominence at the back of the alveolar process, an important landmark for dental anesthesia and muscle attachment
- Anterior nasal spine and nasal notch – form part of the piriform aperture, the bony opening at the front of the nasal cavity
- Incisive canal and foramen – a midline passage in the hard palate carrying the nasopalatine nerve and vessels
- Infraorbital foramen – the exit point on the facial surface through which the infraorbital nerve and accompanying vessels pass to supply the lower eyelid, side of the nose, and upper lip
The Four Processes
- Frontal process – rises to meet the frontal bone, forming part of the nasal bridge area.
- Zygomatic process – extends sideways to connect with the cheekbone
- Palatine process – projects inward to form most of the hard palate
- Alveolar process – extends downward, forming the tooth sockets (alveoli) that hold the upper teeth
Bones That Articulate With the Midface Bone
Each Midface bone articulates with nine bones, making it one of the most interconnected bones in the skull: the frontal, ethmoid, nasal, lacrimal, zygomatic, palatine, and inferior nasal concha bones, the vomer, and the opposite Midface bone at the midline. Notably, these extensive articulations do not include a direct connection to the mandible – a detail that surprises many students learning facial anatomy for the first time.
| Bone | Relationship |
| Frontal bone | Superior |
| Ethmoid bone | Posteromedial |
| Nasal bone | Medial/superior |
| Lacrimal bone | Orbital/nasal region |
| Zygomatic bone | Lateral |
| Palatine bone | Posterior |
| Inferior nasal concha | Nasal surface |
| Vomer | Medial |
| Opposite Midface bone | Midline |
Read More: Maxilla
Because these articulations tie so many bones together, anatomists often describe the Midface bone as the “keystone” of the facial skeleton. It follows that trauma or surgery affecting the Midface bone frequently produces consequences that extend well beyond the bone itself, involving the orbit, nasal cavity, and cheek in the same injury.
What Does the Midface Bone Actually Do?
The Midface bone’s core responsibilities go beyond simply “holding teeth.” Its main functions work together to support everyday eating, breathing, and speaking.
Supporting Mastication
The alveolar process houses the upper teeth, and because the Midface bone itself doesn’t move, it gives the mobile mandible a fixed surface to bite and grind against. Chewing forces generated at the teeth are transmitted upward through the frontal and zygomatic processes into the rest of the skull, distributing load away from the jaw joint.
Separating the Mouth and Nose
The palatine process forms most of the hard palate, physically separating the oral and nasal cavities. This separation allows a person to breathe through the nose while chewing and swallowing at the same time – a function that is disrupted in infants born with a cleft palate, often requiring early surgical correction to support normal feeding and speech development.
Contributing to Voice and Airflow
The paranasal sinuses, including the midface bony sinus, are thought to contribute to the acoustic properties of the vocal tract and help condition inhaled air, though their precise contribution to voice resonance is still debated among researchers. Their air-filled structure also reduces the overall weight of the skull without compromising facial strength.
Framing the Eye Socket
The orbital surface of the Midface bone forms most of the orbital floor, providing structural support beneath the eye and protecting the tissues that support it from below. This is also why orbital floor (“blowout”) fractures are so closely linked to Midface bonery trauma.
The Midface bonery Sinus and Its Drainage Pathway
The Midface bonery sinus is the largest of the four paranasal sinuses and occupies most of the Midface bonery body. It drains through its natural ostium into the middle nasal meatus via the ethmoidal infundibulum, with mucus transported along a defined pathway before exiting near the hiatus semilunaris.
Because the sinus floor sits close to the roots of the upper premolars and molars – separated in some people by only a thin layer of bone – dental infections can spread into the sinus, and sinus disease can occasionally cause pain that mimics a toothache. This overlap is one reason dentists and ENT specialists frequently collaborate on cases involving unexplained upper-jaw pain. The sinus’s orbital-floor relationship also means severe sinus infections or fractures in this region can, in rare cases, affect structures near the eye.
Nerve and Blood Supply of the Midface Bone Region
Sensory innervation of the Midface bone, upper teeth, palate, and adjacent facial tissues is primarily derived from branches of the midface bony division of the trigeminal nerve (CN V2). Key branches include:
- Infraorbital nerve – travels through the infraorbital groove and canal, supplying the lower eyelid, side of the nose, and upper lip
- Superior alveolar nerves (anterior, middle, and posterior branches) – supply the upper teeth and gums
- Nasopalatine and greater palatine nerves – supply the hard palate
Blood supply comes primarily from branches of the Midface bonery artery, including the posterior superior alveolar and infraorbital arteries, which run alongside their corresponding nerves. This close nerve-vessel pairing explains why numbness and localized bleeding often appear together after Midface bonery trauma or dental procedures.
Muscles Attached to the Midface Bone
Several muscles originate from or insert onto the Midface bone, giving it a direct role in facial expression as well as mastication.
| Muscle | Midface bone attachment | Function |
| Levator labii superioris | Frontal process and area above the infraorbital foramen | Raises the upper lip |
| Levator anguli oris | Canine fossa | Raises the corner of the mouth |
| Nasalis | Incisive fossa | Compresses and widens the nostrils |
| Orbicularis oculi | Frontal process, near the orbital rim | Closes the eyelids |
| Buccinator | Alveolar process, opposite the molar teeth | Compresses the cheek during chewing |
| Medial pterygoid (superficial head) | Midface bony tuberosity | Assists in elevating and moving the mandible during chewing |
This muscular network is one reason midface bony fractures can visibly affect facial expression and symmetry, not just chewing or breathing function.
How the Midface Bone Develops
The Midface bone forms through intramembranous ossification – direct bone formation without a cartilage template – beginning around the sixth to seventh week of prenatal development from the Midface bony prominence of the first pharyngeal arch. A separate, small preMidface bony region at the front of the bone gives rise to the sockets for the incisor teeth and fuses with the rest of the Midface bone early in development.
After birth, the Midface bone continues to grow well into the late teens or early twenties. The Midface bony sinus is small and rudimentary at birth and enlarges substantially during childhood as the facial skeleton develops. In adulthood, the alveolar process can undergo significant bone loss (resorption) following long-term tooth loss, a key consideration in denture fitting and dental implant planning.
When the Midface Bone Is Injured: Fracture Patterns and Warning Signs
Midface bony fractures are frequently classified using the Le Fort system, first described in 1901. True Le Fort patterns characteristically involve the pterygoid plates and are classified according to distinct fracture pathways through the midface:
- Le Fort I – a low horizontal fracture separating the tooth-bearing alveolar segment and hard palate from the rest of the Midface bone, producing a “floating palate”
- Le Fort II – a pyramid-shaped fracture running from the nasofrontal suture through the Midface bone and lacrimal bones to the inferior orbital rim, producing a “floating Midface bone”
- Le Fort III – complete craniofacial dysjunction, in which the entire facial skeleton, including the zygomatic arches, separates from the skull base, producing a “floating face”
In practice, facial trauma rarely produces a textbook-clean Le Fort pattern. Many midface injuries combine features of more than one Le Fort type or occur alongside zygomaticomaxillary, orbital, naso-orbito-ethmoid, palatal, or dentoalveolar fractures. Because of this variability, CT imaging is the standard tool used to define the extent and pattern of complex midface fractures and guide treatment planning.
Warning signs of a possible midface bony fracture include a change in bite alignment, facial swelling or asymmetry, numbness across the cheek or upper lip (from infraorbital nerve involvement), nosebleeds, and, in more serious cases, double vision or restricted eye movement. Given the Midface bone’s proximity to the orbit and airway, any of these symptoms after facial trauma warrants urgent evaluation by an oral and maxillofacial surgeon.
Midface Bone in Reconstructive and Orthognathic Surgery
Beyond trauma repair, surgeons reposition or reconstruct the Midface bone for several planned reasons:
- Correcting bite misalignment when the upper jaw sits too far forward, backward, or is vertically uneven relative to the lower jaw
- Restoring structure after tumor removal, where part of the Midface bone may need to be rebuilt using bone grafts or prosthetics
- Repairing congenital differences, such as cleft palate, where the palatine shelves failed to fuse during fetal development
- Adjusting midface projection in orthognathic (jaw) surgery, which can also influence nasal base width and lip support
These procedures require close coordination between oral and maxillofacial surgeons, orthodontists, and sometimes ENT specialists, given how many structures the Midface bone touches.
Midface bone vs. Zygoma vs. Mandible: Quick Comparison
| Bone | Region | Moves During Chewing? | Contains a Sinus? |
| Midface bone | Upper jaw, midface | No (fixed) | Yes – Midface bony sinus |
| Zygoma | Cheekbone | No (fixed) | No |
| Mandible | Lower jaw | Yes (via temporomandibular joint) | No |
Understanding these distinctions matters clinically, since fracture patterns, healing times, and surgical approaches differ significantly between the three bones.
Key Takeaways
The Midface bone connects to nine surrounding bones while quietly performing several jobs at once: anchoring the upper teeth, separating the nose from the mouth, supporting the orbital floor, and housing the body’s largest paranasal sinus. Its extensive articulations and rich neurovascular supply make it structurally efficient but also more vulnerable to complex, multi-structure injuries when trauma occurs. For anyone studying facial anatomy or navigating a maxillofacial diagnosis, understanding these connections makes the bone’s clinical importance far clearer.
Frequently Asked Questions
Is the Midface bone the same as the upper jaw?
Yes, in common usage. The Midface bone is the bone that makes up the upper jaw, though anatomically it does more than hold teeth – it also forms part of the nasal cavity, hard palate, and orbital floor. “Upper jaw” is the everyday term, while “Midface bone” is the precise anatomical name used in clinical and academic contexts.
How many bones does the Midface bone articulate with?
Each Midface bone articulates with nine bones: the frontal, ethmoid, nasal, lacrimal, zygomatic, palatine, and inferior nasal concha bones, the vomer, and the opposite Midface bone at the midline. It does not articulate directly with the mandible, despite both forming part of the jaw.
What structures pass through the infraorbital foramen?
The infraorbital foramen transmits the infraorbital nerve, along with the infraorbital artery and vein, from the orbital floor to the face. These structures supply sensation and blood flow to the lower eyelid, side of the nose, and upper lip, which is why damage near this area often causes numbness in those regions.
Can the Midface bone be reshaped without surgery?
It depends on age and the type of change needed. In adults, repositioning the Midface bone typically requires orthognathic surgery, since mature bone doesn’t remodel significantly on its own. In growing children and adolescents, orthopedic or orthodontic approaches – such as palatal expanders – can influence how the Midface bone develops, and select transverse expansion techniques may still work in some adults depending on skeletal maturity.
What is the Midface bony tuberosity, and why does it matter?
The midface bony tuberosity is a rounded bony prominence at the back of the alveolar process, behind the last upper molar. It serves as an attachment site for part of the medial pterygoid muscle and is an important landmark for dentists administering posterior superior alveolar nerve blocks during dental procedures.
Is the Midface bone affected by osteoporosis or bone loss?
Yes. Like other bones, the Midface bone can lose density with age or due to osteoporosis, and the alveolar process specifically undergoes resorption after tooth loss. This is a key reason older patients or those with long-term missing teeth sometimes require bone grafting before dental implants can be placed.
What’s the difference between a Le Fort fracture and a zygomatic fracture?
Le Fort fractures specifically involve the midface bones and pterygoid plates, classified into three patterns based on how high and how extensively the fracture line runs through the midface. Zygomatic fractures, by contrast, affect the cheekbone and are classified separately, though severe facial trauma can cause both types simultaneously.
Can a midface bony sinus infection spread to the eye?
In rare, severe cases, an untreated midface bony sinus infection can spread to nearby structures, including the orbit, since the sinus sits just beneath the orbital floor. This is uncommon but treated as a medical urgency when it occurs, given the proximity to the eye and its supporting nerves.
Why do dentists sometimes need a panoramic X-ray before midface bony procedures?
A panoramic X-ray gives a wide view of the entire upper and lower jaw in a single image, helping dentists assess bone density, sinus position, and root proximity before procedures like extractions, implants, or sinus lifts. This is especially useful in the Midface bone because of how closely the sinus floor can sit to the tooth roots.
How does aging affect the Midface bone’s appearance?
As people age, natural bone remodeling can reduce Midface bonery bone volume, particularly after tooth loss, contributing to a sunken midface appearance and changes in lip support. This is one reason facial aging assessments in cosmetic and reconstructive medicine often consider underlying skeletal changes, not just skin and soft tissue.