The zygomatic bone is the roughly diamond-shaped bone that forms the prominence of your cheek and the outer rim of your eye socket. Often called the cheekbone in everyday language, it sits at a structural crossroads of the skull, connecting the upper jaw, the temporal bone on the side of the head, and the frontal bone of the forehead. Far from being a passive bump of bone, the zygoma anchors powerful chewing muscles, absorbs bite forces transmitted up through the face, and plays a quiet but surprisingly large role in everything from forensic identification to facial aging.
Where It Sits and What It Connects
The zygomatic bone articulates with four neighboring bones. Its upper edge meets the frontal bone at the outer corner of the eye socket. Its inner surface connects to the maxilla, the main bone of the upper jaw. A slender bridge of bone, the zygomatic arch, extends backward to meet the temporal bone just in front of the ear. And a thin plate reaches back to touch the greater wing of the sphenoid bone deep inside the orbit. Through those four connections the zygoma ties the middle of the face to the braincase, acting as a load-bearing strut that distributes forces generated when you chew.
That structural role is well established in anatomical research. The zygoma has been described as an essential buttress of the facial skeleton for resisting masticatory forces, and it serves as the origin of the masseter muscle, one of the strongest muscles in the body relative to its size, along with several smaller facial muscles.1PubMed Central. Development, Structure, and Function of the Zygomatic Bones: What is New and Why Do We Care? When you clench your jaw or bite into something tough, the masseter pulls from the zygomatic arch and the body of the zygoma, and those forces have to travel somewhere. The bone channels them upward and outward into the thicker bones of the cranial vault, preventing the midface from crumpling inward.
Nerves and Blood Supply Running Through It
A small but clinically important nerve, the zygomatic nerve, passes through the bone itself via tiny channels called foramina. One branch, the zygomaticofacial nerve, exits through a foramen on the front surface of the bone and supplies sensation to the skin over your cheek.2PubMed Central. Bilateral Absence of the Zygomatic Nerve and Zygomaticofacial Nerve and Foramina Another branch, the zygomaticotemporal nerve, exits on the inner side and reaches the skin of the temple. These nerves also carry parasympathetic fibers that contribute to tear production, which is one reason trauma or surgery involving the zygoma can occasionally cause dry-eye symptoms on the affected side.
The foramen itself is not always present. Anatomical studies have documented that some people are born without a zygomaticofacial foramen on one or both sides, meaning the nerve takes an alternative route or is simply absent. This kind of normal variation matters to surgeons, because drilling or plating in the area could damage a nerve that happens to run in an unexpected location.
Normal Anatomical Variations
Most people have a single, undivided zygomatic bone on each side, but a notable minority do not. A recent study of 120 dry skulls found that about one in nine had a bipartite zygomatic bone, meaning an extra suture line divided the bone into two separate pieces.3PubMed. Assessing the frequency and variability of accessory zygomatic sutures in dry skulls: clinical insights and potential implications These accessory sutures were most often oriented posterolaterally, though one skull had a vertical inferior split that had not been reported before. The finding matters practically because a suture line on imaging can be mistaken for a fracture line. Radiologists and emergency physicians who are not aware of this variant may misdiagnose an accessory suture as a crack.
There are also population-level differences in the shape and projection of the zygoma. East Asian populations tend, on average, to have wider and more laterally projecting zygomatic bones, while many European populations have flatter, less prominent cheekbones. These differences are consistent enough that the bone is used in forensic and anthropological work to help estimate ancestry from skeletal remains.
Reading Identity From a Cheekbone
Forensic anthropologists routinely examine the zygomatic bone when working with unidentified skeletal remains. The bone carries signals of both sex and population ancestry, making it useful when a skull is incomplete and other landmarks are missing. In a study comparing Chinese and German skulls, researchers found that sex could be correctly determined about 89% of the time using the full three-dimensional surface shape of the zygomatic bone. Population-related shape differences were captured primarily in the bone’s outline, while the cues for sex were distributed more uniformly across the entire surface.4PubMed. Sexual Dimorphism and Population Affinity in the Human Zygomatic Structure – Comparing Surface to Outline Data
Separate research on South African populations confirmed that males consistently have larger zygomatic bones than females, a difference thought to be driven by hormone-regulated growth and the generally greater muscular robusticity of the male face.5PubMed. Assessing zygomatic shape and size for estimating sex and ancestry in a South African sample Broader mapping of sexual dimorphism across the entire human cranium has identified the medial portion of the zygomatic bone, along with the mastoid processes and the brow ridges, as among the most reliable areas for classifying sex, with accuracy in the low-to-mid seventies percent range when used individually.6Scientific Reports. Mapping sexual dimorphism signal in the human cranium
The Zygoma Through Evolutionary Time
The zygomatic bone tells a rich story across hominin evolution. An analysis of zygomatic root position in fossil and recent hominids found a striking overlap in shape variation across species, with most early hominins falling within the range seen in modern humans. The two clear outliers were the Paranthropines, the “robust” australopithecines known for their massive jaws, and the Neanderthals. Even great apes fell within or near the central shape distribution of the genus Homo, though they separated clearly from gracile and robust australopithecines.7PubMed. Zygomatic Root Position in Recent and Fossil Hominids
The extreme cases illustrate how diet reshapes the face. In Australopithecus boisei, a species adapted to very hard foods, the zygomatic bone flares so far forward and outward that it loses its role as a simple suspensory strut and instead forms a visor-like plate that gains rigidity from its own curvature. By contrast, the Neanderthal zygomatic bone is oriented almost parallel to the sagittal plane, a configuration that helps the face resist torque from powerful biting on the front teeth.8PubMed. Opposing Extremes of Zygomatic Bone Morphology: Australopithecus Boisei versus Homo Neanderthalensis The modern human zygoma sits between these extremes, reflecting our less mechanically demanding diet.
Research on living primates reinforces the diet connection. A study of zygomatic arch root position in haplorhine primates found that species consuming harder or tougher foods tended to have a more anteriorly placed zygomatic root, though the relationship was not universal. Other craniofacial features and behavioral adaptations, such as food processing, can compensate for a less forward position.9PubMed. Zygomatic arch root position in relation to dietary type in haplorhine primates The deeper evolutionary story involves the reorganization of jaw muscles during the transition from early synapsids to modern mammals, a process in which the masseter split into deep and superficial layers and the jaw adductor complex reached its modern configuration.10PubMed Central. Morphological evolution of the mammalian jaw adductor complex
How the Zygomatic Bone Develops
The zygoma forms from cranial neural crest cells and ossifies through intramembranous ossification, meaning bone forms directly in connective tissue without a cartilage template. An interesting developmental wrinkle is that the zygomatic arch is actually built from two bones growing toward each other: the zygomatic bone from the front and the zygomatic process of the temporal bone from the back. How much each bone contributes to total arch length turns out to be genetically coordinated in an inverse relationship. In mice, researchers found that when the zygomatic bone contributes more length, the maxillary zygomatic process contributes less, and vice versa. A region on chromosome 17, with candidate genes including Six2, appears to drive this tradeoff.11PubMed Central. Developmental constraint through negative pleiotropy in the zygomatic arch This kind of genetic push-pull helps explain why the arch can maintain a consistent total length despite variation in its component parts.
Fractures of the Cheekbone
Because the zygoma protrudes from the face, it takes the brunt of many blows. Zygomatic fractures are among the most common facial fractures, typically resulting from assaults, falls, sports injuries, and vehicle collisions. The bone rarely breaks in isolation. Instead, the force usually disrupts multiple suture lines and adjacent thin bones, producing what surgeons call a zygomaticomaxillary complex (ZMC) fracture. A ZMC fracture can involve the orbital floor, the lateral orbital wall, the infraorbital rim, and the zygomatic arch all at once.
One of the most immediate consequences is numbness. The infraorbital nerve, which supplies sensation to the cheek, upper lip, and side of the nose, runs through a canal just below the orbital rim. When a fracture line crosses that canal, or when the bone fragments shift enough to pinch the nerve, the result is loss of feeling across a patch of the mid-face. A retrospective study of 272 patients with ZMC fractures found that fractures running through the infraorbital canal, along with dislocation of the zygomatic complex, were significant predictors of this nerve injury.12PubMed Central. Incidence, Aetiology, and Associated Fracture Patterns of Infraorbital Nerve Injuries Following Zygomaticomaxillary Complex Fractures The numbness usually improves over weeks to months as the nerve heals, but it can occasionally be permanent.
A depressed zygomatic arch fracture can also prevent you from opening your mouth. If the broken arch segment is pushed inward far enough to press against the coronoid process of the mandible, it physically blocks the jaw from moving. One published case involved a man whose mouth opening was limited to just 15 millimeters after the arch collapsed onto the coronoid process.13PubMed Central. Fractured zygomatic arch: a traumatic cause for trismus Jaw locking after cheekbone trauma should prompt imaging even if the initial X-rays looked acceptable, because a standard anteroposterior view can underestimate how far inward the arch has moved.
Eye problems are another concern. A ZMC fracture often increases the bony volume of the eye socket by disrupting the orbital floor or lateral wall, and the eyeball can sink backward into the enlarged space. In a study measuring orbital volumes on CT scans, each additional cubic centimeter of orbital expansion produced roughly 0.7 millimeters of backward eye displacement.14PubMed. Enophthalmos and Orbital Volume Changes in Zygomaticomaxillary Complex Fractures: Is There a Correlation Between Them? Even a couple of millimeters of sunken-eye appearance can be noticeable and hard to correct after the bone heals in a displaced position.
Surgical Repair
Treatment depends on how badly the bone has shifted. Minimally displaced fractures may need nothing more than observation, activity restrictions, and follow-up imaging. When displacement is significant, surgical reduction and fixation become necessary. The standard approach involves open reduction and internal fixation, where the surgeon exposes the fracture sites through small incisions and secures the fragments with titanium miniplates and screws. The number of fixation points matters: a comparison of different approaches found that combining closed reduction with three-point fixation produced the most stable outcomes, while closed reduction alone had the lowest stability.15PubMed Central. Management of zygomatic fractures using different surgical approaches
In practice, the choice of how many fixation points to use varies with injury severity. In a series of nearly a hundred patients, two-point fixation was the most common approach, used in about 42% of cases, followed by single-point fixation in about 23% and three-point fixation in roughly 18%.16PubMed Central. Etiology, Modalities of Zygomaticomaxillary Complex Fracture, open reduction and fixation More fixation points mean more incisions and more hardware, so surgeons balance stability against surgical morbidity.
Access is a practical challenge because the cheekbone is draped in facial nerve branches. Traditional external incisions risk damaging the frontal branch of the facial nerve, which controls forehead movement, or leaving visible scars. Newer techniques use intraoral approaches, reaching the bone through an incision inside the upper lip, with fixation screws passed through a small stab incision in the cheek. This avoids a visible scar and reduces the chance of nerve injury.17PubMed Central. Management of Zygomatic Arch Fractures by Intraoral Open Reduction and Transbuccal Fixation Classifying fractures by how much the bone has shattered at the suture lines, rather than just by where the breaks are, may also help predict who will need reoperation and who will develop complications.18FACE. A Novel Classification Method of Zygomaticomaxillary Complex Fractures by Suture Comminution to Better Predict Clinical Outcomes
When the Cheekbone Is Underdeveloped From Birth
Treacher Collins syndrome is the best-known congenital condition affecting the zygomatic bone. It results from mutations that disrupt the development of cranial neural crest cells, and the zygoma is among the hardest-hit structures. People with the condition typically present with downward-slanting eyelids, underdeveloped ears, and hypoplasia of both the cheekbones and the lower jaw.19PubMed Central. Treacher collins syndrome
The degree of zygomatic underdevelopment varies widely. A study that measured zygomatic bone volume using CT scans found that the average volume in Treacher Collins patients was roughly a third of normal, though individual cases ranged from mildly small and partially intact cheekbones all the way to near-complete absence. In that cohort, about 63% had severe deformities, 21% moderate, and 17% mild.20Plastic & Reconstructive Surgery. A Range of Zygomatic Hypoplasia Exists in Treacher Collins Syndrome Reconstruction usually involves bone grafting or custom implants, often staged over several years as the child’s face grows.
Aging and the Shrinking Midface
Facial aging is not just about skin and fat. The bones underneath change shape too, and the midface is especially affected. Research has shown clearly that the maxilla loses volume with age in people who still have their teeth, contradicting the old orthodontic teaching that midface retrusion happens only after tooth loss. The rate of bone loss is not uniform, though. The maxilla is more susceptible to age-related resorption than the zygoma, meaning the cheekbone holds its shape better than the bone directly below it.21PubMed Central. Changes in the Facial Skeleton With Aging: Implications and Clinical Applications in Facial Rejuvenation This differential loss helps explain a common pattern of facial aging: the cheekbone prominence stays roughly the same while the tissue below it recedes, deepening the nasolabial fold and making the midface look hollow.
Understanding these skeletal changes has shifted how some plastic surgeons approach facial rejuvenation. Instead of only lifting sagging skin, many now focus on restoring lost volume in the maxillary area beneath the cheekbone, using fillers or fat grafting to compensate for the bone that has resorbed. The zygoma itself is less often the target of augmentation for aging, since it retains its projection better than its neighbors.
Cosmetic Reduction Surgery
While Western aesthetic ideals often prize high, prominent cheekbones, the opposite concern is common in parts of East Asia, where wide or strongly projecting zygomatic bones can be seen as making the face look broad or, in some cultural contexts, aggressive or aged.22PubMed. Reduction malarplasty using a zygomatic arch-lifting technique Reduction malarplasty, a procedure to narrow the cheekbone, is one of the most popular facial contouring operations in South Korea and other East Asian countries.
The surgery typically involves an L-shaped cut through the body of the zygomatic bone, accessed through an incision inside the mouth, and a second cut through the zygomatic arch near the ear. The freed bone segment is then pushed inward and fixed with plates or wires. One of the persistent challenges is that the masseter muscle and overlying soft tissue can sag after the bony scaffold beneath them is narrowed. A technique that lifts the arch fragment slightly upward while narrowing it, securing it with a U-shaped microplate, has been developed to counteract this sagging and ensure bone-to-bone contact during healing.23PubMed. Reduction malarplasty using a zygomatic arch-lifting technique The intraoral L-shaped osteotomy approach allows surgeons to reach both the body and the arch without external incisions.24PubMed Central. Intraoral zygoma reduction using L-shaped osteotomy
Zygomatic Implants for Tooth Replacement
In dentistry, the zygomatic bone has become an anchor point for people who have lost most of their upper jaw bone and cannot support conventional dental implants. When the maxilla has atrophied severely, there may not be enough bone to hold a standard implant. Zygomatic implants are much longer than regular dental implants and are angled upward from the upper jaw into the dense bone of the zygoma. A case series of eighteen patients who received zygomatic implants combined with standard implants, loaded immediately with a temporary prosthesis, reported improved stability and reduced the need for bone-grafting procedures.25PubMed Central. Treatment of severe atrophic maxilla with zygomatic implants: a case series The approach is not routine for everyone missing teeth, but for patients with very little upper jaw bone remaining, it can mean the difference between a fixed set of teeth and a removable denture.
Radiation Damage and Other Rare Pathologies
The zygomatic bone is rarely affected by diseases that more commonly target other facial bones, but it is not immune. Osteoradionecrosis, in which bone dies following radiation therapy, occurs in roughly 5% to 38% of patients treated with radiation for head and neck cancers. The mandible accounts for the overwhelming majority of cases because of its blood supply characteristics, but the zygoma can occasionally be affected. One reported case involved zygomatic osteoradionecrosis following removal of a maxillary tumor and subsequent radiation, requiring surgical removal of the dead bone and reconstruction with a forehead flap.26Journal of Craniofacial Surgery. Osteoradionecrosis of the Zygoma
Imaging technology has also changed how zygomatic pathology is detected. Cone-beam CT, a type of three-dimensional imaging that uses less radiation than a standard medical CT scanner, has been shown to detect over a third more fractures in small facial bones than conventional X-rays, with an even larger jump for complex fracture patterns.27PubMed. Direct comparison of conventional radiography and cone-beam CT in small bone and joint trauma For suspected zygomatic fractures that plain films do not clearly show, cone-beam CT offers a practical middle ground between a standard X-ray and a full medical CT scan.