NationMaster - Encyclopedia: Zygomatic bone

The zygomatic bone (malar bone) is a paired bone of the human skull. It articulates with the maxilla, the temporal bone, the sphenoid bone and the frontal bone. It forms part of the orbit and is commonly referred to as the cheekbone. It is situated at the upper and lateral part of the face: it forms the prominence of the cheek, part of the lateral wall and floor of the orbit, and parts of the temporal and infratemporal fossae [Fig. 1]. It presents a malar and a temporal surface; four processes, the frontosphenoidal, orbital, maxillary, and temporal; and four borders. Image File history File links Wiki_letter_w. ... Image File history File links Gray164. ... Image File history File links Gray995. ... Latin is an ancient Indo-European language originally spoken in Latium, the region immediately surrounding Rome. ... It has been suggested that temporal fenestra be merged into this article or section. ... The maxillae are the largest bones of the face, except for the mandible, and form, by their union, the whole of the upper jaw. ... The temporal bones (os temporales) are situated at the sides and base of the skull. ... Figure 1 : Sphenoid bone, upper surface. ... The frontal bone (os frontale, TA: A02. ... In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. ... In anatomy, a process (Latin: processus) is a projection or outgrowth of tissue from a larger body. ...

Surfaces

The malar surface is convex and perforated near its center by a small aperture, the zygomaticofacial foramen, for the passage of the zygomaticofacial nerve and vessels; below this foramen is a slight elevation, which gives origin to the Zygomaticus. The malar surface of the zygomatic bone is convex and perforated near its center by a small aperture, the zygomaticofacial foramen, for the passage of the zygomaticofacial nerve and vessels; below this foramen is a slight elevation, which gives origin to the Zygomaticus. ... Zygomaticus can refer to: Zygomatic bone Zygomaticus minor muscle Zygomatic major muscle Category: ...

The temporal surface, directed backward and medialward, is concave, presenting medially a rough, triangular area, for articulation with the maxilla, and laterally a smooth, concave surface, the upper part of which forms the anterior boundary of the temporal fossa, the lower a part of the infratemporal fossa. Near the center of this surface is the zygomaticotemporal foramen for the transmission of the zygomaticotemporal nerve. The infratemporal fossa is an irregularly shaped cavity, situated below and medial to the zygomatic arch. ... Near the center of the temporal surface of the zygomatic bone is the zygomaticotemporal foramen for the transmission of the zygomaticotemporal nerve. ... The zygomaticotemporal nerve or zygomaticotemporal branch (temporal branch), from the maxillary branch of the trigeminal nerve (Cranial nerve 5), runs along the lateral wall of the orbit in a groove in the zygomatic bone, receives a branch of communication from the lacrimal, and, passing through a foramen in the zygomatic...

Processes

The frontosphenoidal process is thick and serrated, and articulates with the zygomatic process of the frontal bone. On its orbital surface, just within the orbital margin and about 11 mm below the zygomaticofrontal suture is a tubercle of varying size and form, but present in 95 per cent of skulls (Whitnall 43). The supraorbital margin of the frontal bone ends laterally in the zygomatic process, which is strong and prominent, and articulates with the zygomatic bone. ...

The orbital process is a thick, strong plate, projecting backward and medialward from the orbital margin. The orbital process of the the zygomatic bone is a thick, strong plate, projecting backward and medialward from the orbital margin. ...

The maxillary process presents a rough, triangular surface which articulates with the maxilla.

The temporal process, long, narrow, and serrated, articulates with the zygomatic process of the temporal. The zygomatic process of the temporal bone or zygomatic arch is a long, arched process projecting from the lower part of the squamous portion of the temporal bone. ...

Borders

The antero-superior or orbital border is smooth, concave, and forms a considerable part of the circumference of the orbit.

The antero-inferior or maxillary border is rough, and bevelled at the expense of its inner table, to articulate with the maxilla; near the orbital margin it gives origin to the Quadratus labii superioris. The levator labii superioris (or quadratus labii superioris) is a broad sheet, the origin of which extends from the side of the nose to the zygomatic bone. ...

The postero-superior or temporal border, curved like an italic letter f, is continuous above with the commencement of the temporal line, and below with the upper border of the zygomatic arch; the temporal fascia is attached to it.

The postero-inferior or zygomatic border affords attachment by its rough edge to the Masseter. In human anatomy, the masseter is one of the muscles of mastication. ...

Ossification

The zygomatic bone is generally described as ossifying from three centers - one for the malar and two for the orbital portion; these appear about the eighth week and fuse about the fifth month of fetal life. Ossification is the process of bone formation, in which connective tissues, such as cartilage are turned to bone or bone-like tissue. ...

Mall describes it as being ossified from one center which appears just beneath and to the lateral side of the orbit.

After birth, the bone is sometimes divided by a horizontal suture into an upper larger, and a lower smaller division.

In some quadrumana the zygomatic bone consists of two parts, an orbital and a malar. Quadrumana and Bimana form an obsolete division of the primates: the Quadrumana (four-handed ones) being primates with opposable digits (thumbs) on all four limbs, and the Bimana (two-handed ones) being those with opposable digits on the forelimbs only, this latter group contains humans only. ...

Articulations

The zygomatic articulates with four bones: the frontal, sphenoidal, temporal, and maxilla.

Additional illustrations

Beauty

High cheek bones are seen as a sign of beauty in many cultures and is a characteristic of many high fashion models. Model may refer to more than one thing : For models in society, art, fashion, and cosmetics, see; role model model (person) supermodel figure drawing modeling section In science and technology, a model (abstract) is understood as an abstract or theoretical representation of a phenomenon,see; geologic modeling model (economics) model...

See also

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant. Grays Anatomy illustration of a human femur. ... In zootomy, several terms are used to describe the location of organs and other structures in the body of bilateral animals. ... The public domain comprises the body of all creative works and other knowledge—writing, artwork, music, science, inventions, and others—in which no person or organization has any proprietary interest. ... An illustration from the 1918 edition Henry Grays Anatomy of the Human Body, commonly known as Grays Anatomy, is an anatomy textbook widely regarded as a classic work on human anatomy. ...

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Bones of head and neck: the face

maxilla: Body of maxilla - Maxillary sinus
surfaces of body Anterior (Incisive fossa, Canine fossa, Infraorbital foramen, Anterior nasal spine) - Infratemporal (Alveolar canals, Maxillary tuberosity) - Orbital (Infraorbital groove, Infraorbital canal) - Nasal (Pterygopalatine canal)
processes Zygomatic process - Frontal process (Agger nasi, Anterior lacrimal crest) - Alveolar process - Palatine process (Incisive foramen, Incisive canals, Foramina of Scarpa, Premaxilla, Anterior nasal spine) In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. ... Image File history File links Orbital_bones. ... The frontal bone (os frontale, TA: A02. ... The maxillae are the largest bones of the face, except for the mandible, and form, by their union, the whole of the upper jaw. ... Figure 1 : Sphenoid bone, upper surface. ... Your skull is in your back (this is obviously not true, I was just testing the website to see if it really works) The ethmoid bone (os ethmoidale) is a bone in the skull that separates the nasal cavity from the brain. ... The palatine bone is a bone situated at the back part of the nasal cavity between the maxilla and the pterygoid process of the sphenoid. ... The lacrimal bone (Os Lacrimale), the smallest and most fragile bone of the face, is situated at the front part of the medial wall of the orbit . ... Grays Anatomy illustration of a human femur. ... Head and neck anatomy is a specialized study of the human body quite frequently studied in depth by surgeons, dentist, and dental technicians. ... This article or section does not cite its references or sources. ... The maxillae are the largest bones of the face, except for the mandible, and form, by their union, the whole of the upper jaw. ... The body of the maxilla (corpus maxillae) is somewhat pyramidal in shape, and contains a large cavity, the maxillary sinus (antrum of Highmore). ... The maxillary sinus is the largest paranasal sinus. ... The anterior surface is directed forward and lateralward. ... On the anterior surface of the maxilla, just above the eminences corresponding to the incisor teeth is a depression, the incisive fossa, which gives origin to the Depressor alÃ¦ nasi; to the alveolar border below the fossa is attached a slip of the Orbicularis oris; above and a little lateral... Lateral to the incisive fossa is another depression, the canine fossa; it is larger and deeper than the incisive fossa, and is separated from it by a vertical ridge, the canine eminence, corresponding to the socket of the canine tooth; the canine fossa gives origin to the Caninus. ... Above the canine fossa is the infraorbital foramen, the end of the infraorbital canal; it transmits the infraorbital vessels and nerve. ... Medially, the anterior surface of the maxilla is limited by a deep concavity, the nasal notch, the margin of which gives attachment to the Dilatator naris posterior and ends below in a pointed process, which with its fellow of the opposite side forms the anterior nasal spine. ... The infratemporal surface is convex, directed backward and lateralward, and forms part of the infratemporal fossa. ... The infratemporal surface of the maxilla is pierced about its center by the apertures of the alveolar canals, which transmit the posterior superior alveolar vessels and nerves. ... At the lower part of the infratemporal surface of the maxilla is a rounded eminence, the maxillary tuberosity, especially prominent after the growth of the wisdom tooth; it is rough on its lateral side for articulation with the pyramidal process of the palatine bone and in some cases articulates with... The orbital surface is smooth and triangular, and forms the greater part of the floor of the orbit. ... Near the middle of the posterior part of the orbital surface of the maxilla is the infraorbital groove (or sulcus), for the passage of the infraorbital vessels and nerve. ... One of the canals of the orbital surface of the maxilla, the infraorbital canal, opens just below the margin of the orbit. ... The nasal surface presents a large, irregular opening leading into the maxillary sinus. ... On the posterior part of the maxillary surface of the palatine bone is a deep vertical groove, converted into the pterygopalatine canal, by articulation with the maxilla; this canal transmits the descending palatine vessels, and the anterior palatine nerve. ... The zygomatic process of the maxilla (malar process) is a rough triangular eminence, situated at the angle of separation of the anterior, zygomatic, and orbital surfaces. ... The frontal process of the maxilla (nasal process) is a strong plate, which projects upward, medialward, and backward, by the side of the nose, forming part of its lateral boundary. ... The agger nasi is a small ridge on the lateral side of the nasal cavity. ... The lateral margin of the lacrimal fossa is named the anterior lacrimal crest, and is continuous below with the orbital margin; at its junction with the orbital surface is a small tubercle, the lacrimal tubercle, which serves as a guide to the position of the lacrimal sac. ... The alveolar process is the thickened ridge of bone that contains the tooth sockets on bones that bear teeth. ... The palatine process of the maxilla (palatal process), thick and strong, is horizontal and projects medialward from the nasal surface of the bone. ... When the two maxillÃ¦ are articulated, a funnel-shaped opening, the incisive foramen, is seen in the middle line, immediately behind the incisor teeth. ... In the opening of the incisive foramen, the orifices of two lateral canals are visible; they are named the incisive canals or foramina of Stenson; through each of them passes the terminal branch of the descending palatine artery and the nasopalatine nerve. ... In the maxilla, occasionally two additional canals are present in the middle line of the palatine process; they are termed the foramina of Scarpa, and when present transmit the nasopalatine nerves, the left passing through the anterior, and the right through the posterior canal. ... The premaxilla is a pair of small bones at the very tip of the jaws of many animals, usually bearing teeth, but not always. ... Medially, the anterior surface of the maxilla is limited by a deep concavity, the nasal notch, the margin of which gives attachment to the Dilatator naris posterior and ends below in a pointed process, which with its fellow of the opposite side forms the anterior nasal spine. ...

lacrimal bone: Posterior lacrimal crest - Lacrimal groove The lacrimal bone (Os Lacrimale), the smallest and most fragile bone of the face, is situated at the front part of the medial wall of the orbit . ... The lateral or orbital surface of the lacrimal bone is divided by a vertical ridge, the posterior lacrimal crest, into two parts. ... On the nasal surface of the body of the maxilla, in front of the opening of the sinus is a deep groove, the lacrimal groove (or lacrimal sulcus), which is converted into the nasolacrimal canal, by the lacrimal bone and inferior nasal concha; this canal opens into the inferior meatus...

zygomatic bone: Orbital process, Zygomaticofacial foramen - Zygomaticotemporal foramen - Zygomaticoörbital foramina The orbital process of the the zygomatic bone is a thick, strong plate, projecting backward and medialward from the orbital margin. ... The malar surface of the zygomatic bone is convex and perforated near its center by a small aperture, the zygomaticofacial foramen, for the passage of the zygomaticofacial nerve and vessels; below this foramen is a slight elevation, which gives origin to the Zygomaticus. ... Near the center of the temporal surface of the zygomatic bone is the zygomaticotemporal foramen for the transmission of the zygomaticotemporal nerve. ... On the orbital process of the zygomatic bone are seen the orifices of two canals, the zygomaticoÃ¶rbital foramina; one of these canals opens into the temporal fossa, the other on the malar surface of the bone; the former transmits the zygomaticotemporal, the latter the zygomaticofacial nerve. ...

palatine bone: Pterygopalatine fossa - Pterygoid fossa - Horizontal plate (Posterior nasal spine) - Perpendicular plate (Pterygopalatine canal, Sphenopalatine foramen, Pyramidal process)
processes (Orbital - Sphenoidal) The palatine bone is a bone situated at the back part of the nasal cavity between the maxilla and the pterygoid process of the sphenoid. ... In the skull, the pterygopalatine fossa is the space between the lateral pterygoid plate (which is part of the sphenoid bone), and the palate. ... The Pterygoid fossa, or the sphenoid bone is wedged between several other bones in the front of the cranium. ... The horizontal part of the palatine bone (horizontal plate) is quadrilateral, and has two surfaces and four borders. ... Its medial end of the posterior border of the horizontal plate of palatine bone is sharp and pointed, and, when united with that of the opposite bone, forms a projecting process, the posterior nasal spine for the attachment of the Musculus uvulÃ¦. See also anterior nasal spine This article was... The vertical part (perpendicular plate) of the palatine bone is thin, of an oblong form, and presents two surfaces and four borders. ... On the posterior part of the maxillary surface of the palatine bone is a deep vertical groove, converted into the pterygopalatine canal, by articulation with the maxilla; this canal transmits the descending palatine vessels, and the anterior palatine nerve. ... The processes of the superior border of the palatine bone are separated by the sphenopalatine notch, which is converted into the sphenopalatine foramen by the under surface of the body of the sphenoid. ... The pyramidal process of the palatine bone projects backward and lateralward from the junction of the horizontal and vertical parts, and is received into the angular interval between the lower extremities of the pterygoid plates. ... The orbital process of the palatine bone is placed on a higher level than the sphenoidal, and is directed upward and lateralward from the front of the vertical part, to which it is connected by a constricted neck. ... The sphenoidal process is a thin, compressed plate, much smaller than the orbital, and directed upward and medialward. ...

mandible: body (Symphysis menti, Mental foramen, Mylohyoid line) - Ramus mandibulae (Mandibular foramen, Mylohyoid groove, Mandibular canal, Mandibular notch, Condyloid process, Coronoid process) It has been suggested that this article or section be merged with jaw. ... The external surface of the mandible is marked in the median line by a faint ridge, indicating the Symphysis menti or line of junction of the two pieces of which the bone is composed at an early period of life. ... The mental foramen is a foramen in the mandible. ... Extending upward and backward on either side from the lower part of the symphysis of the Mandible is the mylohyoid line, which gives origin to the Mylohyoideus; the posterior part of this line, near the alveolar margin, gives attachment to a small part of the Constrictor pharyngis superior, and to... (ramus mandibulÃ¦; perpendicular portion) The ramus of the mandible is quadrilateral in shape, and has two surfaces, four borders, and two processes. ... The Mandibular Foramen is an opening on the internal surface of the ramus for the mandibular vessels and nerve to pass. ... The margin of the mandibular foramen is irregular; it presents in front a prominent ridge, surmounted by a sharp spine, the lingula mandibulÃ¦, which gives attachment to the sphenomandibular ligament; at its lower and back part is a notch from which the mylohyoid groove runs obliquely downward and forward, and... The mandibular canal runs obliquely downward and forward in the ramus, and then horizontally forward in the body, where it is placed under the alveoli and communicates with them by small openings. ... The upper border of the ramus of mandible is thin, and is surmounted by two processes, the coronoid in front and the condyloid behind, separated by a deep concavity, the mandibular notch. ... The condyloid process is thicker than the coronoid, and consists of two portions: the condyle, and the constricted portion which supports it, the neck. ... The coronoid processis a thin, triangular eminence, which is flattened from side to side and varies in shape and size. ...

others: nasal bone - inferior nasal conchae (maxillary process) - vomer The Nasal Bones (Ossa Faciei & Ossa Nasalia) are two small oblong bones, varying in size and form in different individuals; they are placed side by side at the middle and upper part of the face, and form, by their junction, the bridge of the nose. ... The inferior nasal concha (Inferior Turbinated Bone) extends horizontally along the lateral wall of the nasal cavity [Fig. ... For the embryological structure, see Maxillary prominence. ... The vomer bone is one of the unpaired facial bones of the skull. ...

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