What bones belong to the brain region of the skull. Head skeleton. Anatomical characteristics of the human skull

To brain department The skull (neurocranium) includes 8 bones:

• unpaired- occipital, wedge-shaped, ethmoid, frontal;
• paired- parietal and temporal.

To facial department The skull (splanchnocranium) includes 15 bones:

• unpaired- lower jaw, vomer, hyoid bone;
• paired- maxilla, palatine, zygomatic, nasal, lacrimal, inferior nasal concha.

Bones of the brain. The bones of the brain skull, in contrast to the bones of the facial skull, have a number of features: on their inner surface there are imprints of convolutions and furrows of the brain. Channels for veins lie in the spongy substance, and some bones (frontal, sphenoid, ethmoid and temporal) have air sinuses.

Occipital bone(os occipitale) consists of scales, two side parts and main part. These parts define a large opening through which the cranial cavity communicates with the spinal canal. The main part of the occipital bone fuses with the sphenoid bone, forming a clivus with its upper surface. On the outer surface of the scales there is an external occipital protuberance. On the sides of the foramen magnum are the condyles (articular surfaces that are connected by synastosis with the articular surface of the first vertebra). At the base of each condyle passes the hypoglossal canal.

Occipital bone(outside). 1 - large occipital foramen; 2 - scales; 3 - side part; 4 - condyle; 5 - canal of the hypoglossal nerve; 6 - body (main part); 7 - external occipital crest; 8 - external occipital protuberance

wedge-shaped, or mainbone(os sphenoidale) consists of a body and three pairs of processes - large wings, small wings and pterygoid processes. On the upper surface of the body is the so-called Turkish saddle, in the fossa of which the pituitary gland is placed. At the base of the small wing there is an optic canal (optical opening).

Both wings (small and large) limit the superior orbital fissure. There are three holes on the large wing: round, oval and spinous. Inside the body of the sphenoid bone there is an air sinus, divided by a bony septum into two halves.

Wedge-shaped (main) and ethmoid bone. 1 - cockscomb of the ethmoid bone; 2 - perforated plate of the ethmoid bone; 3 - labyrinth of the ethmoid bone; 4 - hole leading to the sinus of the sphenoid bone; 5 - sinus of the sphenoid bone; 6 - small wing; 7 - large wing; 8 - round hole; 9 - oval hole; 10 - spinous opening; 11 - perpendicular plate of the ethmoid bone; 12 - Turkish saddle of the sphenoid bone; 13 - back of the Turkish saddle; 14 - tubercle of the Turkish saddle; 15 - upper orbital fissure; 16 - visual channel

Ethmoid bone(os ethmoidale) consists of a horizontal, or perforated, plate, a perpendicular plate, two orbital plates and two labyrinths. Each labyrinth consists of small air cavities - cells separated by thin bone plates. Two curved bone plates hang from the inner surface of each labyrinth - the upper and middle turbinates.

frontal bone(os frontale) consists of scales, two orbital parts and a nasal part. On the scales there are paired protrusions - frontal tubercles and superciliary arches. Each orbital part in front passes into the supraorbital region. The airy sinus of the frontal bone (sinus frontalis) is divided into two halves by the bony septum.

Parietal bone(os parietale) has the shape of a quadrangular plate; on its outer surface there is a protrusion - the parietal tubercle.

Temporal bone(os temporale) consists of three parts: scales, stony part, or pyramid, and drum part.

The temporal bone contains the organ of hearing, as well as channels for the auditory tube, internal carotid artery and facial nerve. Outside on the temporal bone there is an external auditory meatus. Anterior to it is the articular fossa for the articular process of the lower jaw. The zygomatic process departs from the scales, which connects with the process of the zygomatic bone and forms the zygomatic arch. The rocky part (pyramid) has three surfaces: front, back and bottom. On its back surface is the internal auditory canal, in which the facial and vestibulocochlear (stato-auditory) nerves pass. The facial nerve leaves the temporal bone through the awl-mastoid foramen. A long styloid process departs from the lower surface of the stony part. Inside the petrous part is the tympanic cavity (middle ear cavity) and the inner ear. The stony part also has a mastoid process (processus mastoideus), inside which are small air cavities - cells. The inflammatory process in the cells of the mastoid process is called mastoiditis.

Temporal bone(right). A - outside view; B - inside view; 1 - scales; 2 - zygomatic process; 3 - front surface of the rocky part; 4 - articular fossa; 5 - sigmoid groove; 6 - the top of the pyramid; 7 - in the upper figure - the drum part; in the lower figure - the internal auditory opening; 8 - styloid process; 9 - external auditory opening; 10 - mastoid process; 11 - mastoid opening

Skeleton and muscles of the head.

Lecture plan:

1. Skeleton of the head.

1.1. Bones of the brain.

1.2. Bones of the facial part of the skull.

1.3. Joints of the bones of the skull.

1.4. Skull as a whole.

1.5. Age features of the skull.

2. Muscles and fascia of the head.

2.1 Mimic muscles

2.2. Chewing muscles.

2.3. Fascia of the head.

3. Muscles and fascia of the neck.

Head skeleton.

The skull (cranium) consists of the brain and facial sections. All bones are interconnected relatively immobile, except for the lower jaw, which forms a combined joint, and the movable hyoid bone, which lies freely on the neck. The bones of the brain skull form a receptacle for the brain, cranial nerves and sensory organs.

To the brain skulls (neuro cranium) include 8 bones:

unpaired - occipital, wedge-shaped, ethmoid, frontal;

paired - parietal and temporal.

To the front skulls (splanchno cranium) include 15 bones:

unpaired - lower jaw, vomer, hyoid bone;

paired - upper jaw, palatine, zygomatic, nasal, lacrimal, inferior nasal concha.

Bones of the brain.

The bones of the brain skull, in contrast to the bones of the facial skull, have a number of features: on their inner surface there are imprints of convolutions and furrows of the brain. Channels for veins lie in the spongy substance, and some bones (frontal, sphenoid, ethmoid and temporal) have air sinuses.

1. Occipital bone(os occipitale) consists of scales, two lateral parts and a basilar part. These parts limit the foramen magnum, through which the cranial cavity communicates with the spinal canal. The main part of the occipital bone fuses with the sphenoid bone, forming a clivus with its upper surface. On the outer surface of the scales there is an external occipital protuberance. On the sides of the foramen magnum are the condyles (articular surfaces that are connected by synastosis with the articular surface of the first vertebra). At the base of each condyle passes the hypoglossal canal.

2. Sphenoid bone(os sphenoidale) consists of a body and three pairs of processes - large wings, small wings and pterygoid processes. On the upper surface of the body is the so-called Turkish saddle, in the fossa of which the pituitary gland is placed. At the base of the small wing there is an optic canal (optical opening).

Both wings (small and large) limit the superior orbital fissure. There are three holes on the large wing: round, oval and spinous. Inside the body of the sphenoid bone there is an air sinus, divided by a bony septum into two halves.

3. Ethmoid bone(os ethmoidale) consists of a horizontal (perforated) plate, a perpendicular plate, two orbital plates and two labyrinths. Each labyrinth consists of small air cavities - cells separated by thin bone plates. Two curved bone plates hang from the inner surface of each labyrinth - the upper and middle turbinates.

4. frontal bone(os frontale) consists of scales, two orbital parts and a nasal part. On the scales there are paired protrusions - frontal tubercles and superciliary arches. Each orbital part in front passes into the supraorbital region. The air-bearing sinus of the frontal bone (frontal) is divided into two halves by the bony septum.

5. Parietal bone(os parietale) has the shape of a quadrangular plate; on its outer surface there is a protrusion - the parietal tubercle, it distinguishes:

Two surfaces - external and internal;

four corners- frontal, sphenoid, occipital and mastoid

6. Temporal bone(os temporale) consists of three parts: scales, stony part, or pyramid, and drum part.

The temporal bone contains the organ of hearing, as well as channels for the auditory tube, internal carotid artery and facial nerve. Outside on the temporal bone there is an external auditory meatus. Anterior to it is the articular fossa for the articular process of the lower jaw. The zygomatic process departs from the scales, which connects with the process of the zygomatic bone and forms the zygomatic arch. The rocky part (pyramid) has three surfaces: front, back and bottom. On its back surface is the internal auditory meatus, in which the facial and vestibulocochlear nerves pass. The facial nerve leaves the temporal bone through the awl-mastoid foramen. A long styloid process departs from the lower surface of the stony part. Inside the petrous part is the tympanic cavity (middle ear cavity) and the inner ear. The stony part also has a mastoid process inside which are small air cavities - cells. The inflammatory process in the cells of the mastoid process is called mastoiditis.

The skull has a facial and brain sections. The border lies between the posterior and orbital margins. The bones of the skull are flat. They are connected by sutures, which enable the growth of all cranial bones. After their ossification, growth stops.

The facial region of the skull consists of the nasal and oral cavities. Unpaired include:

• ethmoid bone;
• coulter;
• hyoid bone.

From the pair stand out:

• upper jaw;
• nasal bone;
• incisive;
• lacrimal;
• zygomatic;
• pterygoid;
• palatine bone;
• lower jaw;
• nasal conchas.

Let us consider in more detail all the bones of the facial skull.

upper jaw

This bone is paired. It consists of a body and four processes. The body includes the maxillary sinus, which communicates with a wide cleft and the nasal cavity. The body consists of the anterior, infratemporal, orbital and nasal surfaces.

In front, the surface has a concave shape. On its border is the infraorbital margin, below which is the infraorbital foramen with nerves and vessels. Under it is a depression in the form of a canine fossa. On the medial edge, the nasal notch is well defined, in which the anterior opening of the nasal cavity is noticeable. The lower edge protrudes and creates the nasal spine.

From the orbital surface, the inferior orbital wall is created, which has a triangular smooth concave shape. In the area of ​​the medial edge, it borders on the lacrimal bone, orbital plate and process. In the posterior part, the border runs along the inferior orbital fissure, from where the infraorbital sulcus begins. In front, it transforms into the infraorbital canal.

The infratemporal surface is created from the pterygopalatine and in front it is delimited by the zygomatic process. The tubercle of the jaw clearly stands out on it, from where the alveolar openings originate, passing into the corresponding canals. Vessels and nerves directed to the molars function through these channels.

The surface of the nose is formed by a complex relief. It unites with the bone of the palate and the lower concha of the nose, passing into the upper part of the palatine process. On the surface, a maxillary cleft in the shape of a triangle is clearly visible. Ahead, a vertical groove is well defined, which is connected to the lower nasal concha and the lacrimal bone.

Further, the bones of the facial skull continue with the frontal process extending from the body of the upper jaw at the point of convergence of the nasal, anterior and orbital surfaces. At one end, the process reaches the nasal part. On the lateral surface, the lacrimal crest lies, passing into the infraorbital region, delimiting the lacrimal groove. On the medial surface of the process is a cribriform ridge that connects with

The zygomatic process, emerging from the jaw, also converges with the zygomatic bone.

The alveolar process is a thick plate, concave on one side and convex on the other, emerging from the jaw. Its lower edge is an alveolar arch with recesses (dental holes) for 8 upper teeth. The separation of the alveoli is provided by the presence of interalveolar septa. Outside, elevations stand out, especially pronounced in the region of the front teeth.

The process of the palate is a horizontal plate. It originates from the nasal surface, from where it passes into its smooth surface from above and creates the lower wall of the nasal cavity. The medial margin bears a raised nasal ridge, which creates a palatine process, uniting with the vomeric margin.

Its lower surface is rough, and palatine grooves stand out on the back. The medial edge is connected to the same process on the other side, whereby a hard palate is created. The anterior margin contains an opening into the incisive canal, while the posterior margin is fused with the palatine bone.

palatine bone

The bones of the facial skull are paired and unpaired. The palatine bone is paired. It includes perpendicular and horizontal plates.

The horizontal plate has four corners. Together with the palatine processes, it makes up the bony palate. The horizontal plate below has a rough surface. The nasal surface, on the other hand, is smooth. Along it and on the process of the upper jaw is the nasal crest, which passes into the nasal bone.

The perpendicular plate enters the wall of the nasal cavity. On its lateral surface there is a large furrow of the palate. She, together with the furrows of the upper jaw and the process of the sphenoid bone, creates a large channel of the sky. There is a hole at the end. On the medial surface of the plate there is a pair of horizontal ridges: one is ethmoid, and the other is conchal.

The orbital, pyramidal and sphenoid processes depart from the palatine bone of the facial section of the skull. The first passes laterally and forward, the second moves down, back and laterally at the junction of the plates, and the third passes back and medially, connecting to the sphenoid bone.

Coulter

The vomer represents the unpaired bones of the facial skull. This is a trapezoidal plate that is located in the nasal cavity and creates a septum. The upper posterior margin is thicker than the other parts. It is divided in two, and the beak and crest of the sphenoid bone pass in the formed groove. The posterior edge separates the choanae, the lower one is connected by the crests of the nose with the palatine bone, and the anterior one is in one part with the nasal septum, and in the other with the plate of the ethmoid bone.

nasal bone

The paired bones of the facial skull are represented by the nasal bone, which creates the bony dorsum. It is a thin plate with four corners, the upper edge of which is thicker and narrower than the lower one. It is connected to the frontal bone, the lateral one - to the frontal process, and the lower one, together with the base of the frontal process, is the boundary of the aperture of the nasal cavity. The anterior surface of the bone has a smooth surface, while the posterior surface is concave, with a ethmoid groove.

lacrimal bone

These bones of the human facial skull are also paired. They are represented by a rather fragile plate in the form of a quadrangle. With it, the anterior wall of the orbit is formed. Anteriorly, it is united with the frontal process, above - with the edge of the frontal bone, and behind - with the plate of the ethmoid bone, the beginning of which covers its medial surface. On the lateral surface is a lacrimal crest with a lacrimal hook at the end. And ahead is the tear trough.

Cheekbone

Another paired bone that combines the bones of the brain and facial skull. It is represented by the orbital, temporal and lateral surfaces, as well as the frontal and temporal processes.

The lateral surface has an irregular quadrilateral shape, the orbital surface forms the wall of the orbit and the infraorbital margin, and the temporal surface forms part of the infratemporal fossa.

The frontal process goes up, and the temporal process goes down. The latter with the zygomatic process forms the zygomatic arch. The bone with the upper jaw is attached to a jagged platform.

Lower jaw

It is the only movable cranial bone. It is unpaired and consists of a horizontal body and two vertical branches.

The body is curved in the form of a horseshoe and has both an internal and an external surface. Its lower edge is thickened and rounded, and the upper one creates an alveolar part with dental alveoli, which are separated from each other by partitions.

In the anterior part there is a chin protrusion, expanding and turning into a chin tubercle. Behind there is a chin opening, behind which an oblique line proceeds.

In the middle of the inner part, the mental spine stands out, on the sides of which there is an oblong 2-abdominal fossa. At the upper edge, not far from the dental alveoli, is the hyoid fossa, under which a weak maxillary-hyoid line originates. And under the line is the submandibular fossa.

The branch of the jaw is a steam room, it has an anterior and posterior edges, an outer and an inner surface. Chewing tuberosity is found on the outer part, and pterygoid tuberosity is found on the inner part.

The branch ends with anterior and posterior processes, which extend upward. Between them there is a notch of the lower jaw. The anterior process is coronal, pointed at the top. The buccal ridge is directed from its base to the molar. And the posterior process, condylar, ends with a head, which continues with the neck of the lower jaw.

Hyoid bone

The bones of the facial part of the human skull end with the hyoid bone, which is located on the neck between the larynx and the lower jaw. It includes the body and two processes in the form of large and small horns. The body of the bone is curved, with the anterior part convex and the posterior concave. Large horns go to the sides, and small ones go up, laterally and back. The hyoid bone is suspended from the cranial bones by means of muscles and ligaments. It is connected to the larynx.

Conclusion

When the bones of the facial skull are studied, anatomy attracts attention primarily with a complex relief on the outer and inner surfaces, which is explained by the fact that the brain, nerve nodes and sensory organs are located here.

The bones are immovable (except for the lower jaw). They are securely fixed due to various sutures in the skull and face, as well as with the help of cartilaginous joints at the cranial base.

6. Skull: departments, bones that form them.

In the skull, a brain region (neurocranium) is distinguished, which contains the brain, and a facial region (splanchnocrania), in which the initial sections of the respiratory and digestive tract are located.

Brain department. The brain skull is formed by unpaired bones: occipital, sphenoid, frontal, ethmoid, and paired: parietal and temporal (see Atl.). Some bones (sphenoid and ethmoid), located on the border of the brain and facial sections, are also functionally involved in the formation of the latter.

Parietal bones (ossa parietalia) almost quadrangular, close the skull from above and from the sides. The convex parts are called parietal tubercles.

Frontal bone (os frontale) adjacent to the front edge of the parietal bones. It consists of scales, orbital and nasal parts (see Atl.). On her convex scales two frontal tubercles protrude in front, below them lie brow ridges, laterally ending cheekbones, and below are two supraorbital foramen, or clippings. On the lower concave surface orbital part at the zygomatic process is located lacrimal fossa, and medially block hole, and sometimes a spike - the place of attachment of the cartilaginous block, through which one of the eye muscles is thrown. Located between the orbital parts nose, covering lattice cut. In the thickness of the frontal bone is frontal sinus, communicating with the nasal cavity.

Occipital bone (os occipitale) participates in the formation of the base and vault of the cerebral skull, which it closes behind and below. The bone is made up of a concave scales, paired lateral parts with jugular processes and with condyles(articulated with the atlas) and main part. These four parts limit large foramen magnum. The foundation of each condyle pierced short canal of the hypoglossal nerve. Laterally from the condyles protrude jugular processes. Across the outer surface of the scales stretch rough upper and bottom notch lines and speaks external occipital protuberance. On the cerebral surface of the scales rises internal occipital protuberance, from which it diverges cruciform elevation with wide grooves from the venous sinuses.

Temporal bones (ossa temporalia) adjacent to the occipital bone. They participate in the formation of the lateral wall and the base of the brain skull, serve as a receptacle for the organs of hearing and balance, the place of attachment of the masticatory muscles and muscles of the neck, and articulate with the lower jaw. Due to the variety of functions, the temporal bone has a complex structure (see Atl.). On its lateral surface is external auditory canal around which are located: on top - scales, behind - the mastoid part, in front and below - the tympanic part and medially - the pyramid. Scales - slightly concave plate closing the brain skull from the side. On it is issued facing forward cheekbone, connecting with the zygomatic bone. Under its base are the articular cavity and tubercle. This is where articulation occurs with the head of the lower jaw. mastoid part forms a mastoid process (place of attachment of muscles), easily palpable through the skin behind the auricle. Inside, the process consists of small air cavities - cells. Unlike other pneumatized bones, they communicate with the middle ear cavity. drum part less than other parts; it limits the external auditory meatus.

Pyramid, or rocky part, contains the tympanic cavity and the cavity of the inner ear. On its posterior surface is internal auditory opening and lateral to it - a slit-like opening vestibule aqueduct. On the front surface, a flat roof of the tympanic cavity and medially from it - arched elevation. At the top of the pyramid is a small fossa of the trigeminal ganglion. On the bottom surface is styloid process and there is an outer hole canal of the carotid artery. This channel passes inside the pyramid and then opens at its top with the opening of the same name. Between the styloid and mastoid processes is located awl mastoid foramen. In the corner between the scales and the pyramid opens musculoskeletal canal, enclosing auditory tube, leading to the middle ear.

Sphenoid bone (os sphenoidale) lies at the base of the cerebral skull and connects with all its bones (see Atl.), as if wedged between them. The bone has a complex structure, since many large nerves pass through it, it participates in the formation of the orbit, temporal and infratemporal fossae, and serves as a site of attachment for the masticatory muscles.

In the bones are distinguished body with an airy sinus, which communicates in front with the nasal cavity (see Atl.). An indentation on the upper surface of the body is called turkish saddle, it houses the endocrine gland - the pituitary gland. On both sides of the body depart big wings; at the base of each of them are sequentially located round, oval and spinous foramen. The anterior surface of the wings forms the lateral wall of the orbit. Above the large wings, bones extend from the body small wings, pierced at the base visual channel, in which the cranial nerve of the same name is located. The small wings are separated from the large ones. upper orbital fissure and participate in the formation of the eye socket. Down from the body depart pterygoid processes, consisting of two (medial and lateral) plates, between which is pterygoid fossa. The base of the processes is pierced pterygoid canal. The processes serve as a site of attachment for muscles.

Ethmoid bone surrounded by other bones so that only its outer part is visible on the whole skull - eye plate, participating in the formation of the medial wall of the orbit (see Atl.). The other part of the bone perforated plate - closes the notch of the frontal bone and is visible from the cerebral surface of the skull. From this plate, a longitudinal cockscomb; serves as a continuation of it into the nasal cavity perpendicular

plate, which is involved in the formation of the nasal septum (see Atl.). Large paired part of the bone labyrinths, consisting of bone cells hang down into the nasal cavity.

In the direction of the perpendicular plate from the labyrinths protrude average and superior turbinates.

Facial department. In the facial skull, unlike the brain, paired bones predominate, which include: maxillary, nasal, lacrimal, zygomatic, palatine and inferior nasal conchas. There are only three unpaired bones: the vomer, lower jaw and hyoid bone (see Atl.).

Maxillary bone (maxilla)- a large paired bone, which occupies a central place in the facial skull, has a body and four processes (see Atl.). Inside body there is a large airway maxillary (maxillary) sinus, opening into the nasal cavity. The front, front surface of the body is concave, has on itself canine fossa, and above it infraorbital foramen channel of the same name, penetrating the entire bone. The upper surface of the body forms the lower wall of the orbit, and the nasal surface forms the lateral wall of the nasal cavity. A small bone is attached to this wall - inferior turbinate. The posterior surface of the bone is facing the infratemporal fossa. Of the four processes extending from the body, frontal connects with the frontal; a zygomatic- with zygomatic bone. Palatine processes together with adjacent to them behind palatine bones (ossa palatina) form solid sky. Alveolar the process is provided with eight holes in which the upper teeth sit.

Nasal bones (ossa nasalia) are located in the region of the nose and close from above pear hole, leading to the nasal cavity. In the depths of the latter is visible coulter (vomer)- a sagittally located plate that adheres to the sphenoid, ethmoid, palatine and maxillary bones.

Lacrimal bones (ossa lacrymaha) - the smallest of the bones of the facial skull. Forming part of the inner wall of the orbit, they are adjacent to the frontal, ethmoid and maxillary bones.

zygomatic bones (ossa zygomatica) have three branches frontal, temporal and maxillary, named after the bones they connect to. The zygomatic bones form the inferolateral edges of the orbits, and together with the zygomatic processes of the temporal bones - cheekbones.

Lower jaw (mandibula)- an unpaired bone, consists of a body and two branches. Front on body issued chin protrusion, and on the sides of it - chin tubercles. On the inner surface of the body in the midline is chin spine, from which two protruding lines extend to the sides. There are 16 tooth sockets on the upper edge of the body. The branches extending from the body form an angle with it, on the inner and outer surfaces of which there are roughness - attachment sites for chewing muscles. Branches end with two processes; of which the front coronary- serves as a place of attachment of the masticatory muscle, and the back - condylar, in which the head and neck are distinguished, it articulates with the temporal bone. There is a hole on the inner surface of the branch mandibular canal, which runs along the roots of the teeth and opens on the outer surface of the body chin hole.

Hyoid bone (os hyoideum) - a small curved bone suspended from the styloid process of the temporal bone with a long ligament (Fig. 1.42). Comprises body, small and big horns. This bone is easy to feel on the neck above the larynx.

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The brain skull is formed

unpaired bones:

• occipital,
• wedge-shaped
• frontal,
• lattice,

paired bones:

• parietal and
• temporal.

Some bones (sphenoid and ethmoid), located on the border of the brain and facial sections, are also functionally involved in the formation of the latter.

1.1. parietal bones

parietal bones (ossa parietalia) almost quadrangular, close the skull from above and from the sides. The convex parts are called parietal tubercles.

1.2. frontal bone

frontal bone (os frontale) adjacent to the front edge of the parietal bones.

It consists of

• scales,
• orbital part
• nasal part.

On her convex scales two frontal tubercles protrude in front, below them lie brow ridges, laterally ending zygomatic processes, and below are two supraorbital foramen, or clippings. On the lower concave surface orbital part at the zygomatic process is located lacrimal fossa, and medially trochlear fossa, and sometimes a spike - the place of attachment of the cartilaginous block, through which one of the eye muscles is thrown. Located between the orbital parts bow, covering lattice cut. In the thickness of the frontal bone is frontal sinus, communicating with the nasal cavity.

1.3. Occipital bone

Occipital bone (os occipitale) participates in the formation of the base and vault of the cerebral skull, which it closes behind and below (Fig. 1.40).

1 - jagged edge;
2 - scales;
3 - large occipital foramen;
4 - condyle;
5 - canal of the hypoglossal nerve;
6 - the main part;
7 - top and
8 - lower cut-out lines;
9 - external occipital protrusion;
10 - external occipital crest;
11 - jugular process

The bone is made up of

• concave scales,
• paired lateral parts with jugular processes and with condyles(joins with atlas)
• main part.

These four parts limit large foramen magnum. The foundation of each condyle pierced short hypoglossal canal. Laterally from the condyles protrude jugular processes. Across the outer surface of the scales stretch rough upper and bottom notch lines and speaks external occiput. On the cerebral surface of the scales rises internal occipital protuberance, from which it diverges cruciform elevation with wide grooves from the venous sinuses.

1.4. temporal bones

temporal bones (ossa temporalia) adjacent to the occipital bone. They participate in the formation of the lateral wall and the base of the brain skull, serve as a receptacle for the organs of hearing and balance, the place of attachment of the masticatory muscles and muscles of the neck, and articulate with the lower jaw.

Due to the variety of functions, the temporal bone has a complex structure. On its lateral surface is

• external auditory canal, around which are:
  • top - scales,
  • behind - mastoid part,
  • front and bottom - drum part,
  • medially - pyramid.
• Scales – slightly concave plate closing the brain skull from the side. On it is issued facing forward cheekbone, connecting with the zygomatic bone. Under its base are the articular cavity and tubercle. This is where articulation occurs with the head of the lower jaw.
• mastoid part forms a mastoid process (place of attachment of muscles), easily palpable through the skin behind the auricle. Inside, the process consists of small air cavities - cells. Unlike other pneumatized bones, they communicate with the middle ear cavity.
• drum part less than other parts; it limits the external auditory meatus.
• Pyramid, orrocky part, contains the tympanic cavity and the cavity of the inner ear. On its posterior surface is internal auditory opening and lateral to it - a slit-like opening vestibule aqueduct. On the front surface, a flat roof of the tympanic cavity and medially from it - arched elevation. At the top of the pyramid is a small fossa of the trigeminal ganglion. On the bottom surface is styloid process and there is an outer hole canal of the carotid artery. This channel passes inside the pyramid and then opens at its top with the opening of the same name. Between the styloid and mastoid processes is located awl mastoid foramen. In the corner between the scales and the pyramid opens musculoskeletal canal, enclosing auditory tube, leading to the middle ear.

1.5. Sphenoid bone

Sphenoid bone (os sphenoidale) lies at the base of the brain skull and connects with all its bones, as if wedged between them. The bone has a complex structure, since many large nerves pass through it, it participates in the formation of the orbit, temporal and infratemporal fossae, and serves as a site of attachment for the masticatory muscles.

In the bones are distinguished body with an airy sinus that communicates anteriorly with the nasal cavity. An indentation on the upper surface of the body is called turkish saddle, it houses the endocrine gland - the pituitary gland. On both sides of the body depart big wings; at the base of each of them are sequentially located round, oval and spinous foramen. The anterior surface of the wings forms the lateral wall of the orbit. Above the large wings, bones extend from the body small wings, pierced at the base visual channel, in which the cranial nerve of the same name is located. The small wings are separated from the large ones. upper orbital fissure and participate in the formation of the eye socket. Down from the body depart pterygoid processes, consisting of two (medial and lateral) plates, between which is pterygoid fossa. The base of the processes is pierced pterygoid canal. The processes serve as a site of attachment for muscles.

1.6. Ethmoid bone

Ethmoid bone (os ethmoidale) surrounded by other bones so that only its outer part is visible on the whole skull - eye plate, involved in the formation of the medial wall of the orbit. The other part of the bone perforated plate - closes the notch of the frontal bone and is visible from the cerebral surface of the skull. From this plate, a longitudinal cockscomb; serves as a continuation of it into the nasal cavity perpendicularplate, which is involved in the formation of the nasal septum. Large paired part of the bone labyrinths, consisting of bone cells hang down into the nasal cavity.

In the direction of the perpendicular plate from the labyrinths protrude average and superior turbinates.

Facial region of the skull

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In the facial skull, unlike the brain, paired bones predominate, which include: maxillary, nasal, lacrimal, zygomatic, palatine and inferior nasal conchas. There are only three unpaired bones: the vomer, lower jaw and hyoid bone.

2.1. maxillary bone

maxillary bone (maxilla)- a large paired bone, which occupies a central place in the facial skull, has a body and four processes. Inside body there is a large airway maxillary (maxillary) sinus, opening into the nasal cavity. The front, front surface of the body is concave, has on itself canine fossa, and above it infraorbital foramen channel of the same name, penetrating the entire bone. The upper surface of the body forms the lower wall of the orbit, and the nasal surface forms the lateral wall of the nasal cavity. A small bone is attached to this wall - inferior turbinate. The posterior surface of the bone is facing the infratemporal fossa. Of the four processes extending from the body, frontal connects with the frontal; a zygomatic- with zygomatic bone. Palatine processes together with adjacent to them behind palatine bones (ossa palatina) form solid sky. Alveolar the process is provided with eight holes in which the upper teeth sit.

2.2. nasal bones

nasal bones (ossa nasalia) are located in the region of the nose and close from above pear hole, leading to the nasal cavity. In the depths of the latter is visible coulter (vomer)- a sagittally located plate that adheres to the sphenoid, ethmoid, palatine and maxillary bones.

2.3. tear bones

tear bones (ossa lacrymaha) - the smallest of the bones of the facial skull. Forming part of the inner wall of the orbit, they are adjacent to the frontal, ethmoid and maxillary bones.

2.4. zygomatic bones

zygomatic bones (ossa zygomatica) have three branches frontal, temporal and maxillary, named after the bones they connect to. The zygomatic bones form the inferolateral edges of the orbits, and together with the zygomatic processes of the temporal bones - cheekbones.

A - outside;
B - from the inside;

1 - body;
2 - branch;
3 - chin protrusion;
4 - digastric fossa;
5 - angle;
6 - chewing tuberosity;
7 - pterygoid tuberosity;
8 - maxillo-hyoid line;
9 - coronoid process;
10 - condylar process;
11 - opening of the mandibular canal;
12 - chin hole

Front on body issued chin protrusion, and on the sides of it - chin tubercles. On the inner surface of the body in the midline is chin spine, from which two protruding lines extend to the sides. There are 16 tooth sockets on the upper edge of the body. The branches extending from the body form an angle with it, on the inner and outer surfaces of which there are roughness - attachment sites for chewing muscles. Branches end with two processes; of which the front coronary- serves as a place of attachment of the masticatory muscle, and the back - condylar, in which the head and neck are distinguished, it articulates with the temporal bone. There is a hole on the inner surface of the branch mandibular canal, which runs along the roots of the teeth and opens on the outer surface of the body chin hole.

Rice. 1.42. Hyoid bone:

A - position in relation to the skull and spine;

B - top view;

1 - body;

2 - small and

3 - big horns

Hyoid bone (os hyoideum) - a small curved bone suspended from the styloid process of the temporal bone with a long ligament (Fig. 1.42).

Comprises body, small and big horns. This bone is easy to feel on the neck above the larynx.