Bones of the facial skull: anatomy. Bones of the facial part of the skull

The shape of the human skull in ogtogenesis undergoes significant changes. During fetal development and in newly born children, the skull is more rounded, since the brain is more developed in it and requires a larger volume of the skull to accommodate it. The shape of the skull changes as the teeth grow and the masticatory muscles are fixed .

Species of the bones of the facial skull

In the skull is the facial and brain departments. The border lies between the posterior and ocular margins. The skull bones are flat. They are joined by seams, which enable growth of all cranial bones. After their ossification growth stops.

The facial part of the skull consists of the nasal and oral cavities. The unpaired are:

• ethmoid bone;
• Opener;
• Hyoid bone.

From the paired stand out:

• Upper jaw;
• Nasal bone;
• Incisive;
• Lacrimal;
• Zygomatic;
• Winged;
• The palatine bone;
• lower jaw;
• Nasal conchas.

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

Upper jaw

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

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

From the orbital surface, the lower orbital wall is created, which has a triangular, smooth, concave shape. In the region of the medial margin, it borders on the tear bone, orbital plate and appendage. In the posterior part, the border passes through the lower orbital fissure, from where the infraorbital furrow begins. From the front it is transformed into the infraorbital canal.

The pendulum surface is created from the pterygo-palatine and inframammary pits. In front it is delimited by the cheekbone process. It clearly stands out the mound of the jaw, from where the alveolar orifices originate, passing into the corresponding canals. Vessels and nerves are directed through these channels to the molars.

The surface of the nose is formed by a complex relief. It combines with the bone of the sky and the inferior shell of the nose, passing into the upper part of the palatine process. On the surface, the maxillary cleft in the form of a triangle is clearly visible. Ahead is well expressed vertical furrow, which is connected with the lower shell of the nose and tear.

Further, the bones of the facial skull are continued by the frontal process, which extends from the body of the upper jaw at the point of convergence of the nasal, anterior and orbital surfaces. One end of the process extends to the nose of the frontal bone. On the lateral surface lies the tear comb, which passes into the infraorbital margin, delimiting the lacrimal furrow. On the medial surface of the appendage there is a latticed crest connected to the malar bone.

The sculiform process, coming out of the jaw, also converges with the malar bone.

The alveolar process is a thick plate, concave on one side, and convex on the other, which extends from the jaw. Its lower edge is an alveolar arch with indentations (denticles) for the 8 upper teeth. The separation of the alveoli is provided by the presence of interalveolar septa. Outdoors, there are elevations, especially distinct in the area of the front teeth.

The outgrowth of the sky is a horizontal plate. It originates from the nasal surface, from where it passes into the alveolar process. Its surface is smooth from above and creates a lower wall of the nasal cavity. The medial edge carries an elevated crest of the nose, which creates a palatine process, merging with the vomerine margin.

Its lower surface is rough, and on the back part there are palatal fissures. The medial edge connects with the same process on the other side, whereby a solid sky is created. The anterior margin contains an opening in the incisal canal, and the posterior is connected to the palatine bone.

The palatine bone

The bones of the facial skull are paired and unpaired. Palatine bone refers to paired. It includes perpendicular and horizontal plates.

The horizontal plate has four corners. Together with the palatine processes it forms the bone skies. The horizontal plate from below has a rough surface. The nasal surface, on the contrary, is smooth. Along it and on the process of the upper jaw there is a nasal crest, turning into the nose bone.

The perpendicular plate enters the wall of the nasal cavity. On its lateral surface is a large fissure of the sky. It, together with the grooves of the upper jaw and the process of the sphenoid bone, creates a large canal of the sky. At its end is a hole. On the medial surface of the plate there is a pair of horizontal ridges: one is latticed, and the other is a shell.

From the palatine bone of the facial part of the skull, the orbital, pyramidal and wedge-shaped processes depart. The first passes laterally and forward, the second extends downward, posteriorly and laterally at the junction of the plates, and the third passes back and medially, connecting to the sphenoid bone.

Vomer

The opener represents the unpaired bones of the facial skull. It is a trapezoidal plate that is located in the nasal cavity and creates a septum. Upper posterior margin thicker than other parts. It is divided in two, and in the formed groove passes the beak and crest of the sphenoid bone. The posterior margin separates the choana, the lower one is joined by the crests of the nose to the palatine bone, and the anterior one in one part with the nasal septum, and in the other with the plate of the latticed bone.

Nasal bone

The bony bones of the facial skull are represented by the nasal bone that creates the bone back. It is a thin plate with four corners, the upper edge of which is thicker and narrower than the lower one. It is connected with the frontal bone, lateral - with the frontal process, and the lower one together with the base of the frontal process is the aperture boundary of the nasal cavity. The anterior surface of the bone has a smooth surface, and the posterior surface - concave, with a lattice 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 quadrilateral. With the help of it, the front wall of the orbit is formed. Ahead it is combined with the frontal process, at the top - with the edge of the frontal bone, and behind - with the plate of the latticed bone, the beginning of which covers its medial surface. On the lateral surface there is a lacrimal comb with a lachrymal crochet on the end. And ahead there is a teardrop groove.

Cheekbone

Another pair of bones, combining the bones of the brain and facial skull. It is represented by the ophthalmic, temporal and lateral surfaces, as well as the frontal and temporal processes.

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

The frontal process extends upwards, and the temporal process extends downwards. The latter with the zygomatic process forms a zygomatic arch. The bone with the upper jaw is attached to the serrated area.

Lower jaw

This is the only mobile cranial bone. It is unpaired and consists of a horizontal body, as well as 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 forms an alveolar part with dental alveoli, which are separated from each other by septa.

In front of the chin protruding, expanding and turning into the chin. Behind there is a chin aperture, behind which comes an oblique line.

In the middle of the inner part of the lower jaw , the chin bone is prominent, on each side of which is an oblong 2-ventral fossa. Near the upper edge, near the dental alveoli, is the hyoid fossa, under which the weak jaw-hyoid line begins. And under the line is a submandibular fossa.

The branch of the jaw is a pair, it has a front and a back edge, the outer and inner surfaces. On the outside, chewing is found, and on the inside - pterygoid tuberosity.

The branch ends in the anterior and posterior processes, which go upward. Between them there is a notch of the lower jaw. Anterior process - coronoid, pointed at the top. The cheek ridge is directed from its base to the molar. A posterior process, condylar, ends with a head that continues with the neck of the lower jaw.

The hyoid bone

Bones of the facial part of the human skull end with a hyoid bone, which is located on the neck between the larynx and the lower jaw. It includes a 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 part concave. Large horns protrude to the sides, and upward, laterally and backward are small. The hyoid bone is suspended from the skull by means of muscles and ligaments. It is connected to the larynx.

Conclusion

When the bones of the facial skull are studied, the anatomy draws attention first of all to the 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 fixed (except the lower jaw). They are securely fixed due to various seams in the area of the skull and face, and also with the help of cartilaginous joints near the cranial base.