The zygomatic bone, also known as the cheek bone or malar bone, is a paired bone located in the facial region of the human skeleton. It is a key component of the facial skeleton, contributing to the shape and structure of the face as well as serving several important functions.
Structure
The zygomatic bone is a complex, irregularly shaped bone that is located in the middle of the face, between the temporal bone and the maxilla. It is comprised of three main parts: the body, the temporal process, and the zygomatic process.
Body
The body of the zygomatic bone is the central, largest part of the bone and is the main contributor to the shape and structure of the cheek. It is roughly quadrilateral in shape and has several important features, including:
Four surfaces
The body of the zygomatic bone has four surfaces – the orbital surface, the temporal surface, the infratemporal surface, and the facial surface.
The orbital surface forms the lateral wall of the orbit and contains the zygomaticofrontal suture, which connects the zygomatic bone to the frontal bone. The temporal surface articulates with the temporal bone and contains the zygomaticotemporal suture, which connects the zygomatic bone to the temporal bone. The infratemporal surface faces inward towards the infratemporal fossa and articulates with the maxilla, palatine bone, and sphenoid bone. The facial surface is the most visible surface of the zygomatic bone and is the part that forms the contour of the cheek.
Four borders
The body of the zygomatic bone has four borders – the superior border, the inferior border, the posterior border, and the anterior border. The superior border forms the highest point of the cheek and is continuous with the temporal process. The inferior border is the lowest point of the cheek and articulates with the mandible at the zygomaticomandibular joint. The posterior border forms the back of the cheek and articulates with the temporal bone. The anterior border forms the front of the cheek and articulates with the maxilla.
Temporal Process
The temporal process is a thin, elongated projection that extends superiorly from the body of the zygomatic bone. It is located on the temporal surface of the bone and articulates with the temporal bone at the zygomaticotemporal suture. The temporal process is an important attachment site for several muscles of the face and head, including the temporalis muscle and the masseter muscle.
Zygomatic Process
The zygomatic process is a thin, elongated projection that extends anteriorly from the body of the zygomatic bone. It is located on the facial surface of the bone and articulates with the maxilla at the zygomaticomaxillary suture. The zygomatic process is an important attachment site for several muscles of the face and head, including the orbicularis oculi muscle and the zygomaticus major muscle.
Location
The zygomatic bone is located in the middle of the face, between the temporal bone and the maxilla. It is a paired bone, with one located on the left side of the face and one on the right side. The zygomatic bones are located superior to the maxilla and inferior to the temporal bone. They are also located posterior to the nasal bone and anterior to the mandible.
It is a key component of the facial skeleton, along with the mandible, maxilla, nasal bone, and frontal bone. Together, these bones form the bony structure of the face, which gives shape and support to the soft tissues of the face, including the skin, muscles, and fat.
Function
The zygomatic bone has several important functions in the human body. These include:
- Structural support: As a key component of the facial skeleton, the zygomatic bone plays a crucial role in providing structural support to the face. It helps to give the face its characteristic shape and contour, and helps to protect the underlying soft tissues of the face from injury.
- Facial expression: The zygomatic bone is an important attachment site for several muscles of the face and head, including the temporalis muscle, masseter muscle, orbicularis oculi muscle, and zygomaticus major muscle. These muscles allow for facial expression, such as smiling and frowning.
- Chewing and swallowing: The zygomatic bone also plays a role in chewing and swallowing. It articulates with the mandible at the zygomaticomandibular joint, which allows for the movement of the mandible during chewing and swallowing.
- Sensation: The zygomatic bone contains several sensory nerve endings, which are responsible for transmitting sensory information to the brain. These nerve endings are important for detecting touch, pressure, and temperature on the face.
Clinical Significance
The zygomatic bone is prone to various types of injury and disease. Some common conditions that can affect the zygomatic bone include:
- Fractures: The zygomatic bone is relatively fragile and can be easily fractured, particularly in cases of trauma to the face. Common causes of zygomatic fractures include car accidents, falls, and sports-related injuries. Zygomatic fractures can cause pain, swelling, bruising, and deformity of the face. Treatment may involve surgery to repair the fracture and restore the normal structure and function of the zygomatic bone.
- Zygomatic complex fractures: A zygomatic complex fracture is a type of fracture that involves the zygomatic bone, the maxilla, and the orbital floor. These fractures are often caused by blunt trauma to the face and can cause significant deformity and functional impairment. Treatment may involve surgery to repair the fractures and restore the normal structure and function of the affected bones.
- Zygomatic osteomyelitis: Zygomatic osteomyelitis is a rare condition in which the zygomatic bone becomes infected with bacteria. It can cause fever, pain, swelling, and redness in the affected area. Treatment may involve antibiotics and surgery to remove the infected tissue.
