The Human Skull Bones
Scientifically, The human Skull Bones, are known as the cranium, consists of 22 bones.
- The skull bones can be broken into two regions, the cranial section and the facial section.
- The cranial bones consist of the bones in the top of the skull while the facial bones consist of the bones that make up your face.
- The skull bones primary functions are protection of the brain and support of the face.
- In the skull, sinal cavities can be found. Although the function of these cavities is still not definitively known, it may be that the sinuses function are to decreasing the weight of the skull bones while maintaining strength.
Below are detailed diagrams of the skull bones (cranial and facial bones). Learn the names of the bones and skull bones anatomy through the skull bones diagrams.
List of all Cranial Bones
List of all Facial Bones
Frontal Skull Bones
- The frontal bone is located at the front of the head / skull and corresponds to the region known as the forehead.
- The main functions of the frontal bone are protection of the brain and support of the face.
- The frontal bones consists of two parts: the vertical portion known as the squama frontalis and the horizantal portion, known as the pars orbitals. The vertical portion corresponds with the forehead while the horizontal portion correlates with the roofs of the orbital (eye) and nasal (nose) cavities.
Parietal Skull Bones
- The two parietal bones are connected and make up part of the roof and sides of the human skull.
- Like the other cranial bones, their main functions include protection of the brain and support of the face. Each parietal bone consists of four borders and four angles.
- The sagittal border, the squamous border, the frontal border, and the occipital border are the four borders of the parietal.
- While the frontal, sphenodial, occipital, and mastoid angles make up the four angles of the parietal bone.
- The temporal bones are situated on the bases and sides of the skull, parallel to the temporal lobes of the brain.
- The primary functions of the temporal bones are protection of the brain and support of the face, specifically the temples.
- Each temporal bone consists of the squama temporalis, mastoid portion, petrous portion, and the tympanic portion.
- Furthermore, mastoid portion and petrous portion. The former consisting of spongy bone and the later consisting of dense bone.
- The occipital bone is a trapezoidal, curvy shaped bone located at the rear of the cranium.
- Like the other cranial bones, this bone protects the brain and supports the head (specifically the back of the head).
- It also contains a gap that allows the cranial cavity to communicate with the vertebral column.
- The occipital bone is divided into three regions, the squama occipitalis, the basilar part, and the lateral parts.
- Furthermore, the occipital bone consists of the superior and inferior angles and the superior and inferior borders.
- The sphenoid bone is located at the base of the skull and behind the eye socket.
- This bone is a wedge-like bone located in front of the temporal bone and is one of several bones that form the eye socket (orbit).
- The sphenoid bone is divided into 6 portions, the body of the bone, two greater wings, two lesser wings, and the pterygoid proccesses.
- Interestingly, the sphenoid bone’s shape can be compared to the shape of a butterfly or bat. See the image to the side to see the anatomy of the sphenoid bone in great detail.
- The ethmoid bone is a square or cubical shaped bone located at the top of the nose and in between the two eye sockets.
- This light weight bone is made out of spongy bone and like the sphenoid, is one of the bones that make up the structure of the eye socket.
- The main functions of the ethmoid bone are the protection of vital organs in the region and support of the nose and orbits (eye sockets).
- Although not relevant to human anatomy, many birds have magnenite deposits in their ethmoid bones that allow them to detect the earth’s magnetic field.
- The mandible bone forms the lower jaw of the human skull bones.
- This bone’s main function is support of the lower part of the face and holding the bottom half of the teeth in place.
- The mandible is essential for movement of the mouth.
- The mandible is divided into several sections, which can be seen in detail in the image to the side.
- The sections of the mandible bone are the body, the two rami, the alveolar process, the condyle, and coronoid process.
- The inferior alveolar nerve is runs through the mandibular foramen (opening) and provides sensation to the teeth.
- The maxilla consists of two separate bones that fuse together to collectively form the maxilla.
- The maxilla, often known as the mustache bone because of its shape, is located above the mandible and below the orbits.
- The function of the maxilla is to provide protection of the face, support of the orbits, hold the top half of the teeth in place, and form the floor of the nose.
The maxilla is divided into the following components: the body,
- the zygomatic process,
- the frontal process,
- the alveolar process,
- the palatine process,
- the infraorbital foramen, and the maxillary sinus.
The alveolar process is known as the maxillary arch and is the portion of the maxilla that hold the upper teeth in place.
- The palatine bone consists of two bones that fuse together to collectively form the palatine, like the maxilla. Often, the palatine is simply known as the palatum.
- This bone is located in the back part of the nasal cavity.
- The palatine bone functions in protection of organs in the region and the formation of the roof of the mouth and floor of the eye socket.
Furthermore, each palatine bone touches six other facial bones:
- the ethmoid,
- the sphenoid,
- the maxilla,
- the inferior nasal concha,
- the vomer,
- and the other palatine.
- The face consists of two zygomatic bones, located in the upper and lateral parts of the face.
- The zygomatic bone, also known as the cheek bone or malar bone, supports the region of the face known as the cheek, protects organs in the area, and forms part of the orbit.
The zygomatic consists of four borders,
- the orbital border,
- the maxillary border,
- the temporal border,
- and the zygomatic border.
Additionally, the zygomatic bone is also known as the zygoma, which is Greek for yoke.
These bones vary in size from individual to individual.
Each nasal bone consists of two surfaces,
- the outer
and inner surfaces
and four borders
The nasal bone functions in support of the nose and formation of the nose bridge.
Furthermore, the nasal bone touches four other bones:
- the frontal,
- the ethmoid,
- the maxilla,
- and the opposite nasal bone.
The main function of the lacrimal bone is forming part of the orbit / eye socket.
The surfaces of the lacrimal bone are
- the orbital surface
- and the nasal surface.
The four borders of the lacrimal bone are
- the anterior,
- and inferior borders
Each lacrimal bone touches four bones:
- the frontal,
- the ethmoid,
- the maxilla,
- and the inferior nasal concha
Inferior Nasal Conchae
- a nasal concha
- or turbinate bone.
Each nasal concha or turbinate is made of spongy bone that curls on itself. The nasal conchae are horizontal bones that project into the nasal cavity.
The primary function of the nasal concahe is the filtering of air. As air enters the nasal cavity during breathing, the nasal conahe forces the air to go through mucous and cilia, thus effectivley filtering and warming the air.
The nasal conchae consists of;
- the medial
- and lateral surfaces.
Additionally, it also consists of the upper border and inferior border.
This bone functions in forming the nasal cavity.
The vomer consists of;
- the superior border
- inferior border
- anterior border
- and posterior border
That is a good start in understanding the Skull Bones of the Human Body and if you would like to learn more click here.