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Description of the presentation Functional anatomy of mimic and chewing muscles and muscles on slides

Functional anatomy of facial and chewing muscles and neck muscles. Fasciae and triangles of the neck. Topography, main anatomical and functional differences between the upper and lower limbs. "He whose face does not radiate light will never be a star" W. Blake

MIMIC MUSCLES HAVE FEATURES that distinguish them from other skeletal muscles 1. They are attached at one end to the bone, the other to the skin 2. They do not have fascia 3. Grouping around natural openings, they change their lumen 4. Through facial expressions they reflect the mental state of a person 5. Participate in articulate speech and act of chewing. The muscles of the head are divided into mimic and chewing

Muscles of the cranial vault The epicranial muscle consists of: 1. from the occipital-frontal muscle, 2. from the temporo-parietal (rudimentary), 3. tendon helmet (supracranial aponeurosis) tendon aponeurosis - a) it is a flat fibrous plate, b) it connects to the hairy skin parts of the head. c) between the aponeurosis and the periosteum there is loose connective tissue, which is perfectly vascularized.

Mimic muscles By position are divided into: A. Muscles surrounding the palpebral fissure B. Muscles around the nasal openings C. Muscles surrounding the oral fissure D. Muscles of the auricle Functionally divided into: I. Sphincters (compressors) and dilators (opening dilators) II. Depressors (lowers) and levators (lifters)

The work of individual muscles 1. The contraction of the frontal abdomen causes an expression of surprise 2. The muscle of the proud. Its contraction causes a "frown" 3. The contraction of the nasal muscle causes a joyful or lustful facial expression.

Contraction of the levator lip muscle - a sign of disapproval - the circular muscle of the mouth - indecision, isolation - cheek muscles - a sense of satisfaction - the large zygomatic muscle - smile, laughter - muscles of laughter - purposefulness - m. raising the corner of the mouth - complacency - m. lowering the corner of the mouth (muscle of "mourning") - sadness - m. lowering the lower lip and chin - perseverance

The simultaneous work of several muscles reflects: - rage (m. proud, part of the circular m. eyes, m. lowering the corner of the mouth) - contempt (m. lowering the corner of the mouth, m. lowering the lower lip) - irony (chin m.) - concentration ( frontal belly of the supracranial m., nasal m., m. lowering the corner of the mouth) - attention (frontal belly of the supracranial m., circular m. of the eye, m. wrinkling eyebrow)

Specific facial expressions in certain diseases Hippocratic mask (in a patient with cholera) Face of a patient suffering from myxedema Face of a patient suffering from parkinsonism (expression of violent laughter) Unilateral paralysis (facial asymmetry)

CHECKING MUSCLES - provide mechanical grinding of food - participate in articulate speech - their work also reflects the emotional state of a person (the appearance of nodules when emotions are restrained - spastic contraction of the chewing muscle; participation in laughter, reflection of horror, gnashing of teeth in a fit of anger)

MUSCLES OF THE NECK Topographically divided into: - Superficial (subcutaneous muscle of the neck, sternocleidomastoid m.) - Muscles attached to the hyoid bone - Suprahyoid (bigastric, stylohyoid, chin-hyoid, maxillo-hyoid) - Subhyoid (sternohyoid, sternothyroid, thyroid-hyoid, scapular-hyoid) - Deep - Scalene (anterior, middle, posterior) - Rectus muscles of the head and neck

Fascia of the neck, fascia cervicalis has three plates: superficial plate, lamina superficialis pretracheal plate, lamina pretrachealis prevertebral plate, lamina prevertebralis

Cellular spaces: 1. Supra-sternal interfascial space with a superficial plate in front and between the pretracheal plate behind 2. Previsceral space with the pretracheal plate in front between and behind the trachea - 3. Posterior visceral space - with the back wall of the pharynx in front and between the prevertebral plate behind 4. Carotid vagina (vagina carotica) Clinical significance Pozadivisceral space is filled with loose fiber, through which inflammatory processes from the neck can spread into the chest cavity.

13 Comparative aspects and topography of the extremities. In the process of evolution of human limbs, his forelimbs became upper limbs. They have lost their supporting function and their locomotor function has significantly expanded and become more complex, which ensured their transformation into a labor organ. The hind limbs became lower. They retained their locomotor function, but their function associated with the support of the body and its balance increased sharply.

141. 1. Axillary fossa, fossa axillaris - visible when the upper limb is abducted. Due to the changed functions of the limbs, transformations occurred in their structure (bones, ligamentous apparatus, muscles, neurovascular structures, topographic formations) I. TOPOGRAPHICAL FORMATIONS OF THE UPPER LIMB

152. 2. Axillary cavity, cavitas axillaris - visible during dissection and removal of skin and subcutaneous tissue in the axillary fossa. Contents of the axillary cavity: Axillary artery and vein, long nerves of the brachial plexus. 4 walls respectively: Medial wall - serratus anterior muscle Lateral wall - biceps brachii and coracobrachialis muscle

16 Anterior wall - pectoralis major and minor. Triangles are distinguished on it: 1) Clavicular-thoracic, trigonum claviopectorale (limited to the clavicle and pectoralis minor muscle) 2) Pectoral, trigonum pectorale (limited to the edges of the pectoralis minor muscle) 3) Inframammary, trigonum subpectorale (limited to the lower edges of the pectoralis minor and major muscles) Within these triangles are branches a. axillaris and their companion veins.

17 Trilateral foramen Quadrilateral foramen Subscapularis teres major The long head of the triceps muscle. Surgical neck of the humerus. The back wall is formed by 1. latissimus dorsi, 2. teres major, and 3. subscapularis. There are 2 holes within this wall: The trilateral hole is located medially, limited: at the top by the lower edge of the subscapularis muscle, from below by the large round muscle, laterally by the long head of the triceps muscle) The artery surrounding the scapula passes here

18 Trilateral foramen Quadrilateral foramen Subscapularis teres major The long head of the triceps muscle. Surgical neck of the humerus. The quadrilateral opening is limited at the top - by the lower edge of the subscapularis muscle, from below - by the large round muscle, laterally - by the surgical neck of the shoulder medially - by the long head of the triceps muscle of the shoulder Here the posterior artery surrounding the humerus and the axillary nerve pass

19 On the shoulders there are 3 topographic formations: - between the biceps muscle of the shoulder and the shoulder muscle, 2 grooves are formed: 3. Medial biceps groove, sulcus bicipitalis medialis. It contains the brachial artery and veins and the median nerve 4. Lateral biceps sulcus, sulcus bicipitalis lateralis. This groove is deeper and longer, extending to the axillary cavity. The cephalic vein passes through it. The biceps muscle of the shoulder

5. Canal of the radial nerve, canalis nervi radialis, or brachial canal, canalis humeromuscul a fig. It is formed by the groove of the radial nerve on the humerus and the medial and lateral heads of the triceps brachii. Contents of the canal: radial nerve and deep artery and veins of the shoulder, lymphatic vessels.

21 In the ulnar region on the anterior surface, there are: 6. ulnar fossa, fossa cubitalis, Its bottom is formed by the shoulder muscle. The fossa is limited: from above and laterally - m. brachialis, medially - m. pronator teres within the fossa there are: 7. Medial anterior ulnar sulcus, sulcus cubitalis anterior medialis (ulnaris), laterally limited - m. brachioradialis, medially - m. brachialis 8. Lateral anterior ulnar groove, sulcus cubitalis anterior lateralis (radialis), laterally limited - m. pronator teres, medially - m. brachialis brachioradialis pronator teres. shoulder muscle

22 On the back surface on the sides of the olecranon there are 2 grooves 9. Posterior medial ulnar groove 10. Posterior lateral ulnar groove, in which the ulnar nerve passes In all four ulnar grooves there are anastomoses between the branches of the brachial, ulnar and radial artery Olecranon

23 On the front surface of the forearm there are: 11. Ulnar groove, sulcus ulnaris Borders: medially - elbow. fold. wrist lateral. - superficial. fold. fingers Contents: ulnar nerve, artery, veins 12. Radial sulcus, sulcus radialis Borders: medially - beam. wrist flexor lateral. - brachioradialis muscle Contents: radial artery and veins superficial branch of the radial nerve 13. Median sulcus, sulcus medianus Borders: medial. - superficial. fold. lateral fingers. - radial fold. wrist Contents: median nerve 1 1 1 2 1 3 flexor retinaculum

24 In the area of ​​the wrist, from the thickened part of the fascia, the following are formed: 14. The flexor retinaculum (on the palmar surface). It spreads over the groove of the wrist, turning the latter into a channel in which they pass: vagina communis musculorum flexorum u vagina tendinis musculi flexoris pollicis longi, which end at the level of the distal phalanges thumb and little finger. The three middle fingers have isolated vagina tendinum digitorum manus flexor retinaculum

2515. The extensor retinaculum (located on the back side). The space under the retainer is divided by fibrous bundles into 6 canals, in which 8 muscle tendon sheaths are located: 1. vagina tendinis m. abductoris pollicis longi et v. t. m. extensoris pollicis brevi. 2. v. t. musculi extensoris carpi radialis longi et brevis. 3. v. t. musculi extensoris pollicis longi 4. v. t. musculi extensoris digitorum et v. t. musculi extensoris indicis 5.v. t. musculi extensoris digiti minimi 6. v. t. musculi extensoris carpi ulnaris.

261. Several topographic formations are formed in the pelvic region. The piriformis muscle, passing through the large sciatic foramen, divides it into supra- and sub-piri-shaped foramen: 1. supra-piri-shaped foramen, foramen suprapiriforme - the superior gluteal nerve, artery and veins pass through it. 2. piriform opening, foramen infrapiriforme - through it pass: the lower gluteal, sciatic, pudendal nerves, posterior cutaneous nerve of the thigh, lower gluteal, internal pudendal artery and veins of the same name 3. Obturator canal, canalis obturatorius - between the obturator groove and the upper the edge of the obturator internus muscle, 2-2.5 cm long. The nerve, artery and veins of the same name pass through it. II. TOPOGRAPHIC FORMATIONS OF THE LOWER LIMB

284. Muscular gap: It is limited in front and above - inguinal ligament behind - ilium medial. – iliopectineal arch Contents: iliopsoas muscle femoral nerve 5. Vascular lacuna: It is limited in front and above – inguinal ligament behind and below – pectinate ligament lateral. - iliopectineal arch medially - lacunar ligament Contents: femoral artery and vein femoral branch of the femoral-genital nerve muscle lacunae psoas major muscle vascular lacunae iliopectineal arch inguinal ligament

29 Within the thigh and there are: 6. Femoral triangle, trigonum femorale: Borders: from above - inguinal ligament laterally - sartorius muscle medially - adductor longus muscle Furrows within the triangle: iliac - pectineal groove, sulcus ileopectineus (in it lie - the femoral artery, vein, nerve) femoral groove, sulcus femoralis (the femoral artery and vein, saphenous nerve lie in it)

307. Adductor canal, canalis adductorius Walls of the canal: medial - large adductor muscle lateral - medial wide muscle of the thigh anterior - fibrous plate, thrown between the indicated muscles Contents: femoral artery and vein of the same name saphenous nerve adductor canal

318. Popliteal fossa, fossa poplitea Borders: from above and laterally - the biceps femoris muscle from above and medially - the semitendinosus and semimembranosus muscles from below - the heads of the gastrocnemius muscle Contents (from back to front): tibial Nerv popliteal Vein Ne. VA popliteal artery

32 On the lower leg there are: 9. Ankle-popliteal canal, canalis cruropopliteus: Walls: behind - the cambius and povida muscle in front - the posterior tibia. muscle Contents: posterior tibial artery and veins tibial nerve 10. Superior musculo-peroneal canal, canalis musculofibularis superior: Walls: fibula (in the upper third) long peroneal muscle Contents: superficial. fibula nerve 11. Inferior musculoperoneal canal, canalis musculofibularis inferior: Walls: fibula (in the middle third) long flexor of the thumb Contents: peroneal artery and veins

33 On the plantar surface of the foot there are: 12. Medial plantar groove, sulcus plantaris medialis: Borders: medial. - muscle that abducts the thumb laterally - short flexor of the fingers back more - tibial artery) and veins of the same name a b

34 I. Differences in the skeleton of the limbs Upper limb 1. There are 32 bones in the skeleton of the limb 2. The mass of bones is 1/3 of the total mass of the skeleton 3. The bones are graceful and relatively weak 4. The girdle of the upper limb consists of two bones. Lower limb 1. There are 30 bones in the skeleton of the limb 2. The mass of bones is 1/2 of the total mass of the skeleton 3. The bones are less elegant, powerful and strong 4. The girdle of the lower limb consists of one bone

35 II. Differences in limb joints Upper limb 1. Has 34 joints with a large range of motion 2. Minimum ligaments (eg, only one lig. coracohumerale in the shoulder joint). 3. Small congruence articular surfaces 4. Extensive movements of the bones of the forearm - pronation and supination 5. Specific carpal-metacarpal joint of the thumb (saddle-shaped) providing opposition of the first finger to the rest - oppositio and repositio 6. The shoulder joint is the most mobile, i.e., provides movements with large amplitudes Lower limb 1. Has 29 joints with little range of motion 2. More ligaments (eg five ligaments in the hip joint) 3. Very large articular congruence. surfaces 4. Less mobility of the bones of the lower leg - pronation and supination is carried out only in knee joint with its bent position 5. Specific arch of the foot, characteristic only for the human foot. Its formation is due to the upright posture of a person. 6. The hip joint is less mobile, because the range of motion in it is much less

36 III. Differences in the muscles of the limbs Upper limb 1. 38 muscles 2. Mostly dynamic 3. Small mass 4. The ratio of the mass of the extensor to the mass of the flexors 1: 1, 042 5. There is a group of muscles that provide movement of the girdle of the upper limb. 6. There are 8 highly differentiated muscles that provide movement in the carpometacarpal joint of the thumb. Lower limb 1. 49 (57) muscles 2. Predominantly static 3. Large mass 4. Ratio of extensor mass to flexor mass 3:1 arch of the foot

37 I V. Differences in the function of the limbs Upper limb 1. Is a tool of labor. Evolutionarily, they perform the function of a support only in early childhood and in some sick people. The upper limbs reflect the mental state of a person through gestures. 2. The joints (especially the hands) are functionally more differentiated. 3. The shoulder girdle is very mobile (well-pronounced synsarcosis) Lower limbs 1. Provides for holding the body in a vertical position and moving it in space. The foot performs the function of a spring apparatus. 2. The joints of the foot are functionally less differentiated. There are arches in the foot. 3. The bones of the pelvic girdle are practically motionless

38 V. Differences in the vessels and nerves of the limbs Upper limb 1. Arterial palmar arches are parallel to each other in the same frontal plane 2. A small number of valves in the veins 3. Very differentiated receptor formations, V in large numbers located in the skin of the fingertips - sensory function

All facial muscles have the following features: they are devoid of fascia, are woven into the skin, and when they contract, change the position and depth of skin folds. Muscles are under control nervous system and, contracting, create a certain facial expression that reflects the mental state of a person. Mimic muscles are concentrated near the oral, nasal, orbital and ear openings and are anatomically independent of each other, but in the formation of facial expressions, functional combinations of many muscles are possible that change the position of skin folds and the size of the above facial openings.

Muscles surrounding the mouth

The circular muscle of the mouth (m. orbicularis oris) is a wide circular ribbon starting from the edge of the red border of the lips and reaching the nasal septum at the top, and below the chin-labial groove. This muscle from above, from the side and from below is radially penetrated by numerous muscles, which, contracting, all together stretch the oral fissure. With selective contraction of individual bundles, the shape and position of the lips or the angle of the oral fissure change, which occurs during articulation, eating and chewing.

Function. When contracted, it closes the oral fissure.

The muscle lifting the upper lip and wing of the nose (m. Levator labii superioris alaeque nasi) represents three bundles that start from the wing of the nose, the frontal process of the upper jaw and the infraorbital edge of the zygomatic bone. All three heads are connected near the nasolabial fold, weaving into the skin.

Function. With the reduction of all parts, the nasolabial fold and partially the upper lip rise, which happens with laughter and a smile. In the event that the circular muscle is contracted, it is possible to expand the nasal openings.

The large and small zygomatic muscles (mm. zygomatici major et minor) start from the front surface of the zygomatic bone, go down and medially. The muscle is woven into the middle of the nasolabial fold of the upper lip and the upper part of the angle of the oral fissure.

Function. Pulls the corner of the mouth and raises the nasolabial fold. Participates in the act of laughter.

The muscle that lifts the corner of the mouth (m. Levator anguli oris) is the deepest muscle. It begins in the region of the canine fossa of the upper jaw. Attaches to the top of the corner of the mouth.

Function. Raises the corner of the mouth and the upper lip in the region of the incisors.

The muscle of laughter (m. risorius) is represented by a thin and tender bundle that starts from f. parotidis and is woven into the skin of the corner of the mouth.

Function. When contracted, it pulls the corner of the mouth.

The muscle that lowers the lower lip (m. depressor labii inferioris) is a deep muscle. It starts from the base of the lower jaw and is woven into the lower lip.

Function. Lowers lower lip.

The muscle that lowers the corner of the mouth (m. depressor anguli oris) starts from the base of the lower jaw and is attached to the corner of the mouth in the form of a triangular plate.

Function. Lowers the corner of the mouth, smoothing the nasolabial fold and bending the chin-labial fold, which gives the face an expression of sadness and grief or neglect and alienation.

The chin muscle (m. men talis) starts from the alveolar process in the region of the lower incisors and is woven into the skin of the chin.

Function. With bilateral contraction, it lifts the skin of the chin and increases the curvature of the chin-labial fold. The lower lip, resting in this case against the motionless skin of the chin, turns inside out.

The buccal muscle (m. buccinator) limits the vestibule of the mouth. Its muscle bundles are located in a horizontal plane. It starts outside from the alveolar process of the upper jaw, respectively, 1-3 large molars, from raphe pterygomandibularis and crista buccinatoria mandibulae and ends in the circular muscle of the mouth. The muscle is covered with fascia, which is a continuation of the superficial fascia of the neck. At the level of the 2nd large molar of the upper jaw, the duct of the salivary parotid gland perforates the muscle. Outside, between the buccal muscle, skin, angle of the mouth and the coronoid process of the lower jaw, there is a fatty body of the cheek (corpus adiposum buccae), well developed in children.

Function. Pulls the corner of the mouth, flattens both lips, pressing them to the front teeth.

Muscles around the nose

The nasal muscle (m. nasalis) in humans, unlike many mammals, is poorly developed. It starts from the alveolar process of the upper jaw at the level of the second incisor and is divided into three bundles: pars transversa - attaches to the back of the nose, compresses the cartilaginous part of the nose during contraction; pars alaris - attached to the wing of the nose and lowers it; pars depressor septi - attached to the cartilaginous part of the nasal septum, lowers it when contracted.

Muscles surrounding the eye

The circular muscle of the eye (m. orbicularis oculi) is a thin circular plate that has three parts: the orbital, eyelid and lacrimal.

The orbital part (pars orbitalis) starts from the medial ligament of the eyelids, the frontal process of the upper jaw and the nasal part of the frontal bone, then with a wide concentric ribbon is located around the entrance to the orbit. The upper edge of the muscle overlaps the beginning of m. frontalis, lower - the beginning of m. zygomaticus, m. levator labii superioris, descending below the infraorbital foramen.

Function. With the contraction of this part of the muscle, the eyebrow drops, the cheek rises and thus the entrance to the orbit decreases.

The eyelid part (pars palpebralis) is located under the skin of the upper and lower eyelids. It starts from the medial ligament of the eye and goes to the lateral angle, where the bundles mutually intersect.

Function. With the contraction of the secular part of the muscle, the upper eyelid drops by 8-10 mm, and the lower eyelid rises by 2-3 mm. In this case, not only the closing of the palpebral fissure occurs, but also the wetting of the cornea with a tear. The mechanism of this muscle is as follows. With an open palpebral fissure, the curvature of the muscle that surrounds the eyeball is greater than with closed eyelids. Since the beginning and attachment of the muscle are at fixed points, when it contracts, shortening and a decrease in curvature occur, which corresponds to the curvature of the eyeball. As a result, when the muscles contract, the edges of the eyelids tend to take a position in which the curvature of the muscle will be the smallest. The sliding of the eyelids over the eyeball is facilitated by the fact that the conjunctival layers of the eye are moistened with tears.

The lacrimal part (pars lacrimalis) is an underdeveloped muscle. It is located between the upper eyelid and the wall of the orbit. It starts from the crista lacrimalis posterior and, passing behind the lacrimal sac, connects to the posterior edge of the pars palpebralis.

Function. The contraction of the lacrimal part of the muscle exerts pressure on the posterior wall of the lacrimal sac. As a result, the tear is squeezed out of the sac towards the nasolacrimal duct. The action of this muscle is more effective when the palpebral fissure is closed.

The muscle wrinkling the eyebrow (m. corrugator supercilii) is located under the pars orbitalis of the circular muscle of the eye and the final part of m. frontalis. It starts from the nasal part of the frontal bone and the frontal process of the upper jaw, goes to the medial part of the skin of the eyebrow.

Function. When contracting, the muscle not only lowers the medial part of the eyebrow skin, but also brings it closer to the midline. At the same time, oblique or vertical skin folds are formed above the nose.

All the facial muscles described above are innervated by branches of the VII pair of cranial nerves.

Muscles of the outer ear

The muscles of the outer ear in humans are not well developed. This is due to the release of articulatio atlantoaxial mediana, which contributed to an increase in head mobility. The function of moving the auricle towards the sound disappeared.

There are anterior, superior and posterior muscles of the ear (mm. auriculares anterior, superior et posterior). Starting from the fascia, they are attached to the auricle.

innervation: due to the branches of the VII pair of cranial nerves.

Function. When reduced, they cause a slight displacement of the auricle and its tension.

Muscles of the skull

The supracranial muscle (m. epicranius) has two bellies: venter frontalis et occipitalis. Both bellies pass into a wide thin aponeurosis. The frontal abdomen ends in the skin of the eyebrows and, when contracted, raises the eyebrows. The occipital abdomen starts from the linea nuchae superior and, when contracted, stretches the aponeurosis.

The aponeurosis of the supracranial muscle is loosely connected with the bones of the skull and is firmly fused with the skin.

innervation: due to the branches of the VII pair of cranial nerves.

Chewing muscles

Chewing muscle (m. masseter) (Fig. 184), steam room, palpable under the skin in the regio parotideomasseteris. It has a superficial part starting from the zygomatic process of the upper jaw and the zygomatic arch, which is oriented downward and backward and is attached to the angle of the lower jaw, to its tuberosity of the same name. The deep part starts from the zygomatic arch and the deep layer of the temporal fascia and is attached together with the superficial part.

The chewing muscle develops great strength, as it has a significant moment of rotation.

Function. Raises the lower jaw and is the main muscle in the act of chewing, applying force to the molars.

The temporal muscle (m. temporalis), steam room, has a wide beginning along the entire temporal line of the scales of the temporal bone and a deep sheet of the temporal fascia. Attached to the coronoid process of the lower jaw. The anterior muscle bundles have a vertical position, and the posterior ones are located at an angle of 30 ° to the horizontal line.

Function. The anterior bundles raise the lower jaw and apply force to the incisors and canines. These features of the function can explain the well-developed temporal muscles in predators. The posterior bundles displace the protruding lower jaw backward.

Lateral pterygoid muscle (m. pterygoideus lateralis), steam room, has a triangular shape and is located horizontally. It starts from the infratemporal crest of the greater wing of the sphenoid bone, from the root and outer surface of the lateral plate of the pterygoid process. The muscle bundles are sent back and attached to the pterygoid fossa and the neck of the condylar process. The upper bundles are woven into the joint capsule that covers the articular disc.

Function. With bilateral contraction, the lower jaw is pushed forward. When one muscle contracts, the lower jaw moves in the opposite direction.

The medial pterygoid muscle (m. pterygoideus medialis), steam room, has an orientation of muscle bundles similar to the masticatory muscle. It begins in a fossa bounded by the lateral and medial plates of the pterygoid process. It is attached to the inner surface of the angle of the lower jaw.

Due to m. masseter and m. pterygoideus medialis, a muscular loop is formed, covering the lower jaw in the region of the angle.

Function. Raises the lower jaw, acting mainly on the molars.

The masticatory muscles develop from the mesenchyme of the first gill arch and are innervated by the third branch of the trigeminal nerve.

It often happens that people with dissimilar facial features still have a lot in common. appearance. For example, they may have the same smile, or they may both wrinkle their foreheads when they are upset. This similarity is given to us by the same facial expressions, which are determined by the facial muscles of the face and the facial nerves with which these muscles are innervated. The site has prepared an article about the anatomy of the face, its muscles, nerves, blood vessels and the anatomical structure in general. It will help you learn more about your own physiology, the structure and location of muscles, their contraction, and will also be useful to cosmetologists when studying muscles to perform a rejuvenating facial massage.

Anatomical structure of the face

The face is considered to be the head section, the upper boundary of which runs along the upper orbital margin, the zygomatic bone and the zygomatic arch to the auditory opening, and the lower boundary is the jaw branch and its base. Simplifying this medical definition, it can be noted that the face is the region of the head, the upper part of which is the eyebrows, and the lower part is the jaw.

The following areas are concentrated on the face: orbital (including the infraorbital region), nasal, oral, chin and lateral regions. The latter consists of: buccal, parotid-chewing and zygomatic regions. It also contains receptors for visual, gustatory and olfactory analyzers.

human face skeleton

Regardless of how well developed the muscles of the face are, it is the skeleton that determines its appearance. Representatives of the stronger sex are characterized by a powerful bone skeleton, small eye sockets and strongly pronounced superciliary arches, while women are distinguished by less pronounced facial bones, rounded eye sockets and wide short noses.

The skull can be divided into two sections: the bones of the skull and the bones of the face. Directly in the skull are the brain, eyes, organs of hearing and smell. Facial part of the skull or bones of the face - form the frame of the face.

The human face consists of paired and unpaired bones. These include:

• upper jaw;
• palatine bone;
• cheekbone.

Unpaired:

• lower jaw;
• hyoid bone.

All bones are fixedly connected to each other by sutures and cartilaginous joints. The only movable part is the lower jaw, which is connected to the skull by the temporomandibular joint. At birth, a person has a rounded face shape, since the bone skeleton is very poorly developed. Over time, it transforms, some cartilage is replaced by bone tissue. The formation of the face ends at the age of 16-18 for women and at 20-23 for men.

It happens that people are born with defects in the facial bones and cartilage - their deformation due to various factors: birth trauma, or, for example, a genetic disease. The quality of life of such people is greatly deteriorating not only in aesthetic terms, but also in physiological terms. With improper fusion of bones and nasal cartilage, breathing problems occur. Sometimes a person, having difficulty in inhaling / exhaling, begins to breathe through his mouth, which leads to negative consequences. This kind of problem is solved by plastic surgery, namely rhinoplasty.

Nerve branches on the human face

There are twelve pairs of cranial nerves in total. Each of them is indicated by the order of the Roman numerals. There are many nerve branches on the face, the functioning of which is closely related to the facial muscles. Inflammation of these nerves can lead to various changes in appearance and violation of the symmetry of the face. Nerve fibers go from the nuclei to the muscles:

1. olfactory nerve - to the organs of smell;
2. visual - to the retina;
3. oculomotor - to the eyeball;
4. block - to the upper oblique muscle;
5. trigeminal - to chewing muscles;
6. abducent - to the lateral rectus muscle;
7. facial nerve - to facial muscles;
8. vestibulocochlear - to the vestibular department;
9. glossopharyngeal - to the stylopharyngeal muscle, parotid gland, pharynx and posterior third of the tongue;
10. wandering - to the muscles of the pharynx, larynx and soft palate;
11. additional - to the muscles of the head, shoulder and shoulder blades;
12. the hypoglossal nerve innervates the muscles of the tongue.

1. Olfactory nerve.

Responsible for olfactory sensitivity. On the surface of the nasal mucosa there are neurons of special sensitivity - olfactory. Neurosensory cells transmit information through the neural circuit to the anterior parahippocampal gyrus, which is the associative zone of the olfactory system. So, pleasant smells inevitably simultaneously cause a salivation reflex, and unpleasant smells - vomiting, nausea. Perception is also closely related to the formation of the taste of food.

2. Optic nerve.

The fibers of the optic nerve begin in the neurons of the retina, pass through the vascular, white membranes of the eye and the orbit, forming in the fat body the beginning of the optic nerve and the ophthalmic part of the nerve, entering the optic canal. The fibers end in the occipital lobe. The optic nerve transmits impulses (a photochemical reaction of rods and cones in the retina) to the visual center of the occipital lobe of the cerebral cortex, where this information is processed.

3. Oculomotor nerve.

This is a mixed nerve, consisting of two types of nuclei. Starting from the tire of the legs of the brain, which lie flush with the upper mounds of the roof of the midbrain, the nerve fibers are divided into two branches, the upper of which approaches the muscle that lifts the upper eyelid, and the lower, in turn, is divided into three more branches innervating the medial rectus the muscle of the eye, the lower rectus muscle and the oculomotor root, heading to the ciliary node. The nuclei of the oculomotor nerve provide adduction, elevation, lowering and rotation of the eyeball, innervating 4 of the 6 oculomotor muscles.

4. Block nerve.

Its nuclei originate from the tegmental pedunculus at the level of the inferior colliculus of the midbrain roof. It goes around the brain stem from the lateral side, exits the fissure near the temporal lobe, following the wall of the cavernous sinus, enters the orbit through the superior orbital fissure. Innervates the superior oblique muscle of the eye. Provides a turn of the eye to the nose, abduction outwards and downwards.

5. Trigeminal nerve.

It is a mixed nerve, combining sensory and motor intermediate nerves. The former transmit information about the sensitivity of the skin of the face (tactile, pain and temperature), nasal and oral mucous membranes along with impulses from the teeth and temporomandibular joints. The motor fibers of the trigeminal nerve innervate the chewing, temporal, maxillofacial, pterygoid muscles, as well as the muscle responsible for the eardrum.

6. Abducens nerve.

Its nucleus is located in the back of the brain, projecting into the facial tubercle. The fibers exit in the groove between the bridge and the pyramid, through the hard shell of the brain, entering the cavernous sinus, enters the orbit, lying under the oculomotor nerve and innervating only one oculomotor muscle - the lateral rectus muscle, which provides abduction of the eyeball outward.

7. Facial nerve.

It belongs to the group of cranial nerves and is responsible for the innervation of the facial muscles of the face, the lacrimal gland, as well as the taste sensitivity of the anterior part of the tongue. It is motor, but on the basis of the brain, the intermediate nerves responsible for taste and sensory perception join it. The defeat of this nerve causes peripheral paralysis of the innervated muscles, which leads to a violation of the symmetry of the face.

8. Vestibulocochlear nerve.

It consists of two different roots of special sensitivity: the first carry impulses from the semicircular ducts of the vestibular labyrinth, the second - conduct auditory impulses from the spiral organ of the cochlear labyrinth. This nerve is responsible for the transmission of auditory impulses and our balance.

9. Glossopharyngeal nerve.

This nerve plays a very important role in the anatomy of the face. It is responsible for the motor innervation of: the parapharyngeal gland (thus providing its secretory function), the muscles of the pharynx, the sensitivity of the soft palate, tympanic cavity, pharynx, tonsils, soft palate, Eustachian tube, and also for the taste perception of the back of the tongue. In addition to the motor fibers of the sensory fibers inherent in the nerves described above, the glossopharyngeal nerve also has parasympathetic ones. In case of fractures of the base of the skull, aneurysm of the vertebral and basilar arteries, meningitis and a number of other disorders, damage to the lingual nerve can occur, which leads to such consequences as the loss of taste perception of the posterior third of the tongue and the sensation of its position in the oral cavity, the absence of pharyngeal and palatine reflexes, such as and other deviations.

10. Vagus nerve.

Contains the same set of nerve fibers as the glossopharyngeal: motor, sensory and parasympathetic. It innervates the laryngeal and striated muscles of the esophagus, as well as the muscles of the soft palate and pharynx. Carries out parasympathetic innervation of the smooth muscles of the esophagus, intestines, lungs and stomach, cardiac muscle along with sensitive innervation of the external auditory canal, the tympanic membrane and the area of ​​the skin behind the ear, as well as the mucous membrane of the lower pharynx and larynx. Affects the secretion of the stomach and pancreas. Unilateral damage to this nerve causes sagging of the soft palate on the side of the lesion, deviation of the uvula to the healthy side and paralysis of the vocal cord. With bilateral complete paralysis of the vagus nerve, death occurs.

11. Accessory nerve.

Consists of two types of nuclei. The first is a double nucleus, located in the posterior sections of the medulla oblongata, and it is also the motor nucleus of the glossopharyngeal and vagus nerves. The second - the nucleus of the accessory nerve, is located in the posterolateral section of the anterior horn of the gray matter of the spinal cord. Innervates the sternocleidomastoid muscle, which provides tilt to its side cervical, raises the head, shoulder, shoulder blade, rotates the face in the opposite direction, brings the shoulder blades to the spine.

12. Hypoglossal nerve.

The main function of this nerve is the motor innervation of the tongue, namely: the styloglossus, chin-lingual and hyoid-lingual muscles along with the transverse and rectus muscles of the tongue. With a unilateral lesion of this nerve, the tongue shifts to the healthy side, and when protruded from the mouth, it deviates towards the lesion. In this case, atrophy of the muscles of the paralyzed part of the tongue occurs, which practically does not affect speech and chewing functions.

The listed nerves of the face in the process of innervation of the facial muscles set the facial expressions of the individual.

Mimic muscles of the face

The muscles of the face, contracting, shift certain areas of the skin, giving the face all kinds of expressions, which is why they are called "mimic". The mobility of certain areas of the skin of the face is due to the fact that the facial muscles begin on the bones of the cranium, connecting with the skin, they are also devoid of fascia. Most of them are concentrated near the eye, mouth and nasal openings. There are such mimic muscles:

• Supracranial (occipital-frontal) - pulls the scalp back, raises eyebrows, forms transverse folds on the forehead;
• Proud muscle - responsible for the formation of transverse folds above the bridge of the nose, with muscle contraction on both sides;
• The muscle wrinkling the eyebrow - contracting, forms vertical folds on the bridge of the nose, reduces the eyebrows to the midline;
• The muscle that lowers the eyebrow - lowers the eyebrow downward and slightly inward;
• The circular muscle of the eye - provides squinting and closing of the eyes, narrowing the palpebral fissure, smoothes the transverse folds on the forehead, closes the palpebral fissure, expands the lacrimal sac;
• The circular muscle of the mouth - is responsible for narrowing the mouth and pulling the lips forward;
• The muscle lifting the corner of the mouth - pulls the corner of the mouth up and outward;
• Laughter muscle - pulls the corner of the mouth to the lateral side;
• Muscle lowering the corner of the mouth - closes the lips, pulls the corner of the mouth down and out;
• Cheek muscle - determines the shape of the cheeks, presses the inner surface of the cheeks to the teeth, pulls the corner of the mouth to the side;
• The muscle that lifts the upper lip - forms the nasolabial fold during contraction, raises the upper lip, expands the nostrils;
• Large and small zygomatic muscles - forms a grin, raising the corners of the mouth up and to the sides, can also be the cause of dimples on the cheeks;
• The muscle that lowers the lower lip - pulls the lower lip down;
• Chin muscle - wrinkles the skin of the chin, pulls it up, forming pits on it, stretches the lower lip;
• Nasal muscle - slightly raises the wings of the nose;
• Anterior ear muscle - shifts the auricle forward and upward;
• Upper ear muscle - pulls the ear up;
• Back ear muscle - pulls the ear back;
• Temporoparietal muscle - with its help we can chew food.

All of them can be divided into two large groups according to the performing function: constrictors - allow you to close your eyes, mouth, lips and dilators - responsible for their opening.

The main role in the blood supply to the face is played by the carotid artery - all facial arteries originate from it. Two arteries are responsible for blood flow to the face, tongue and other organs of the oral cavity: the lingual and the facial.

lingual artery takes its base from the anterior wall of the external carotid artery, a few centimeters above the superior thyroid artery. Its trunk is located in the submandibular region and serves as a guideline for determining it during surgical interventions. After the lingual artery passes into the root of the tongue and provides blood supply to its muscles, mucous membrane and tonsils. Also, separate branches of this artery supply the diaphragms of the mouth, sublingual and mandibular glands.

Facial artery begins a centimeter above the lingual, originating at the anterior surface of the external carotid artery. It rises up the face, touching the posterior surface of the submandibular gland, after which it goes around the lower edge of the lower jaw. Its route runs to the corner of the mouth, then goes to the side of the nose to the medial corner of the eye between the superficial and deep mimic muscles. This section of the facial artery is called the angular artery. The palatine, mental, lower labial and upper labial arteries also branch off from it.

A large role in the blood supply to the face is taken by the mass of capillaries and the lower ophthalmic vein. The latter does not have valves; blood enters it from the eye muscles and the ciliary body. Sometimes blood passes through it into the pterygoid plexus if it leaves the orbit through the infraorbital fissure.

We hope our article was useful for you and you learned the most important thing about the location of the facial muscles, blood vessels and nerves. And the site site opened for you the curtain of that part of the body that is hidden from our eyes under the skin.

Muscles of the head and neck: brief information about the main muscle groups, points of attachment, functions. Sleep triangle.

The muscles of the head are divided into muscles of the face (mimic) and chewing muscles. The muscles of the face are thin muscle bundles, which, unlike other muscles, have only one point of attachment on the bones, and the other end is woven into the skin or into other muscles. They are located just under the skin, so they are devoid of fascia. When contracting, certain areas of the scalp are displaced, giving the face a certain expression (facial expression). Most of them are located around the natural openings of the face and reduce or increase them. By changing the position of the lips, cheeks, facial muscles are involved in the act of speech, in moving food in the oral cavity during chewing. The masticatory muscles during contraction displace the lower jaw, causing the act of chewing, and participate in articulate speech.

Chewing muscles 4 pairs, all of them are attached to the lower jaw at one end and participate in the act of chewing.

chewing muscle starts from the lower edge of the zygomatic arch; attached to the masticatory tuberosity of the lower jaw. Raises the lower jaw.

temporalis muscle- wide, fan-shaped, occupies the temporal fossa. It starts from the temporal surface of the large wing of the sphenoid bone, the scales of the temporal bone, partially parietal and frontal, attaches to the coronoid process of the lower jaw. Raises the lower jaw, the anterior bundles pull it upward anteriorly, the posterior bundles back.

Lateral pterygoid muscle- located in the infratemporal fossa. It starts from the lateral plate of the pterygoid process and the large wing of the sphenoid bone, is attached to the neck of the articular process of the lower jaw, the capsule and the articular disc of the mandibular joint. With a unilateral contraction, it shifts the jaw in the opposite direction, with a bilateral contraction, it pushes it forward.

medial pterygoid muscle- starts from the pterygoid process of the sphenoid bone, attaches to the pterygoid tuberosity on the inner surface of the angle of the lower jaw. With a unilateral contraction, it shifts the jaw in the opposite direction, with a bilateral contraction, it pushes forward and raises it.

Mimic muscles.

supracranial muscle located in the region of the cranial vault. It includes a large aponeurosis - a tendon helmet, into which muscle formations are woven: in front - the frontal abdomen, behind - the occipital abdomen, on the side - ear muscles (weakly developed in humans). The aponeurosis is loosely fused with the bones of the skull and closely - with the skin of the scalp, with muscle contraction it shifts along with the skin. The frontal abdomen starts from the skin of the eyebrows - raises the eyebrows and forms transverse folds on the forehead. The occipital belly starts from the nuchal line of the occipital bone and displaces the scalp backwards.

Circular muscle of the eye- surrounds the palpebral fissure, flat, elliptical. It consists of 3 parts: orbital (located along the edge of the orbit), secular (in the thickness of the eyelids) and lacrimal (attached to the lacrimal sac). Closes the eyelids, closes the eyes, promotes the outflow of tears from under the eyelids into the lacrimal sac, pulls the eyebrows down, smoothes the wrinkles on the forehead.

Orbicular muscle of the mouth- formed by circular muscle bundles in the thickness of the lips. It starts in the skin of the corner of the mouth from the facial muscles, attaches to the skin near the midline. Closes the mouth gap and pulls the lips forward.

Muscle that raises the upper lip: infraorbital rim / jaw - skin of the nasolabial fold.

Muscle that lifts the corner of the mouth: canine fossa - skin of the corner of the mouth.

Muscle that lowers the lower lip- from the base of the lower jaw to the skin of the lower lip.

Eyebrow wrinkling muscle- from the superciliary arch to the skin of the eyebrows. Forms longitudinal folds on the bridge of the nose.

nasal muscle- consists of transverse and wing parts. Narrows the nasal openings, lowers the wings of the nose.

buccal muscle- forms the lateral wall of the oral cavity. It starts from the upper and lower jaws in the region of the alveoli of the large molars, is woven into the circular muscle of the mouth. He presses his cheeks to his teeth.

Large and small zygomatic muscles- from the lateral surface and infraorbital edge of the zygomatic bone and is woven into the circular muscle of the mouth and the skin of the corner of the mouth. Pull the corner of the mouth up and out.

In the own fascia of the head, 4 sections are distinguished:

1) Temporal fascia

2) Chewing

3) Fascia of the parotid gland

4) Cheek-pharyngeal fascia

In the neck area, part of the muscles acts on the spinal column, changing the position of the head. Another part of the muscles associated with the hyoid bone lowers the lower jaw and changes the position of the larynx. Some muscles, attached to the ribs and collarbones, are auxiliary respiratory muscles. Depending on the location, the muscles of the neck are divided into superficial, deep and median (muscles of the hyoid bone).

They are located mainly in the face and, together with chewing, belong to the group of muscles of the head. In many cases, the facial and chewing muscles function together: when swallowing, chewing, yawning and, most importantly, articulate speech.

Mimic muscles

The main purpose of facial muscles is reflected in the name - this is the formation of facial expressions. Located directly under the skin, the facial muscles, when contracted, shift the skin, which leads to the formation of various folds and wrinkles on it, giving the face a particular expression.

With complex sensations (emotions), such as joy, shame, pain, grief, nerve impulses are sent from the cerebral cortex along the facial nerve to the facial muscles. Numerous combinations of contractions of these muscles determine the richest variety of facial expressions. It is on the example of mimic muscles that the close connection of the nervous system with skeletal muscles is clearly visible. Fine structure, great mobility, as well as proximity to the most important sense organs were the basis on which the role of facial muscles arose and developed as spokesmen for human mental experiences.

Mimic muscles are thin muscle bundles that are attached to the bones of the skull at one end, and woven into the skin at the other. Therefore, their reduction causes a displacement of skin areas and determines facial expressions. When the facial muscles are relaxed, the skin, due to its elasticity, returns to its original state. Withering of the skin, increased dryness leads to a decrease in its elastic properties and the formation of wrinkles.

Located in groups around the natural openings of the face: eye sockets, mouth, nose, the facial muscles are involved in closing or expanding these openings and provide mobility for the cheeks, lips and nostrils. Muscle bundles have a circular or radial direction. The circular muscles are the closing holes, the radial muscles are dilators.

Some of the most important facial muscles located around the mouth and eyes are described below.

Orbicular muscle of the mouth
The circular muscle of the mouth lies in the form of circular muscle bundles under the skin of the lips and around them. Other muscles of the face are woven into it, heading towards the mouth opening. Contracting, the circular muscle closes the mouth opening. The contraction of its individual sections causes a variety of lip movements. The most peripheral areas, when contracted, lead to the folding of the lips into a tube, which occurs at the time of the kiss. Together with the buccal muscle, the circular muscle of the mouth plays leading role in sucking movements, therefore it is already well developed in a newborn child.

The levator lip and the levator anguli originate on the maxilla near the lower edge of the orbit. They pull the corner of the mouth up and thus raise the upper lip; separate bundles attached to the wings of the nose dilate the nostrils. The contraction of these muscles leads to a deepening of the nasolabial fold, stretching from the wing of the nose to the corner of the mouth.

The muscle that lowers the corner of the mouth begins with a wide base on the lower jaw, and the apex is woven into the skin of the corner of the mouth. When contracted, it straightens the nasolabial fold, pulls down the corner of the mouth, giving the face an expression of sadness, as well as discontent and even contempt. The nearby muscle that lowers the lower lip has a square shape and is involved in the expression of horror, irony, anger.

Chin muscle
The mental muscle, lying deeper than the previous ones, begins on the alveoli of the incisors and goes down to the skin of the chin. This muscle lifts and wrinkles the skin of the chin, protruding the lower lip forward. Children do the same when they are about to cry.

zygomatic muscles
In the expression of joy, the zygomatic muscles take part, moving from the zygomatic bone to the corner of the mouth and pulling it up and to the side, and the laughing muscle, which extends in a thin bundle from the corner of the mouth to the skin of the cheek. These muscles stretch the mouth when laughing and smiling. The muscle of laughter owes its origin to the “dimples” on the cheeks.

buccal muscle
The thickness of the cheek is formed by the buccal muscle, which is sometimes called the trumpeter muscle. Its functions are associated with sucking (especially in infants) and chewing, since when contracted, it presses the cheek against the teeth, helping to move the chewed food. The figurative name of the muscle is associated with its ability to also blow air out of the mouth when playing wind instruments or when whistling. The mimic role of the buccal muscle is to expand the mouth when laughing or crying. It is this muscle that can hurt after a long laugh. The duct of the parotid salivary gland passes through this muscle, the opening of which opens on the inner surface of the cheek. On top of the buccal muscle under the skin is an accumulation of fatty tissue, which determines the swelling of the cheek, which is better expressed in children and women.

Circular muscle of the eye
The circular muscle of the eye consists of circular bundles that surround the orbit and are woven into the skin of the eyelids. With the reduction of its middle part, located arcuately between the inner and outer edges of the eyelids, the eyelids close - this happens when blinking and during sleep. The outer part of the muscle runs along the edge of the orbit; contracting, it closes the eye, and also causes the lacrimal fluid to move to the inner corner of the palpebral fissure. Small deep muscle bundles are attached to the walls of the lacrimal sac, which lies near the inner corner of the eye, and expand it, thereby facilitating the outflow of tears into the lacrimal sac and further into the nasal cavity.

The muscle that lifts the upper eyelid and is located in the orbit opens the eye. By its origin, this muscle does not belong to the mimic.

The muscle that wrinkles the eyebrows is also connected to the eye socket. It is woven into the skin of the eyebrows and, when contracted, brings the eyebrows together, forming longitudinal folds between them. This gives the face an expression of pain and suffering.

Muscle of the proud
In the region of the bridge of the nose there are vertical bundles of the proud muscles, which start from the nasal bone and are woven into the skin of the forehead. They form short transverse folds over the bridge of the nose, giving the face an arrogant expression.

supracranial muscle
The supracranial muscle, which covers the entire scalp and forehead, has a significant length. It consists of the so-called tendon helmet, which is firmly fused with the skin. Muscular parts are woven into the tendon helmet: in front - the frontal muscle, behind - the occipital, and in the region of the auricle - three poorly developed ear muscles. The contraction of the occipital muscle tightens the tendon helmet and the skin of the scalp, smoothes the wrinkles of the forehead. With the contraction of the frontalis muscle, the eyebrows rise, and the skin of the forehead gathers into transverse folds, giving the face an expression of surprise.

Of practical importance is the fact of a strong fusion of the tendon helmet with the skin of the scalp. As a result, with the contraction of the supracranial muscle, the hairline also shifts. Hematomas formed during bruises and injuries in this area of ​​the head take the form of “bumps”, since blood from damaged vessels cannot spread in the subcutaneous tissue, but stretches the elastic skin in a limited area. The scalp, known from adventure novels, also includes a tendon helmet, since the latter is firmly fused with the skin, but weakly connected to the bones of the skull.

ear muscles
The ear muscles are rudimentary, that is, well developed in animals, but have lost their significance in humans. Distinguish between the upper, anterior and posterior ear muscles. They are almost incapable of contracting, but some people can "move their ears" with their help. The largest upper ear muscle gives a person the opportunity to slightly raise the auricle. And in most mammals, the facial muscles are located mainly around the auricle and serve to orient it in the direction of the captured sounds.

Muscles of the mouth
In human ancestors, the ear musculature receded into the background and muscles began to develop, concentrated around the mouth opening. The participation of the lips in articulation contributes to the separation of individual muscle bundles in this area. The development of other facial muscles in the course of evolution is associated with their role in food intake and protection of the sense organs from strong irritations and adverse environmental influences.

Features of the evolution of facial muscles

In their development, the facial muscles are closely related to the wide subcutaneous muscle, which is well developed in many mammals. In humans, a thin sheet of subcutaneous muscle remained on the neck, where it extends from the edge of the lower jaw to the collarbone and somewhat lower. With a strong pull of the corner of the mouth down and to the side, it can be made visible. The functional significance of the subcutaneous muscle of the neck in humans is to stretch the skin of the neck in order to prevent compression of the superficial veins when the head is tilted.

Mimic muscles have reached such a perfect development in humans in connection with the acquisition of the ability to upright posture and the release of the upper limb for labor activities. This made it possible to free the jaw apparatus from the functions of defense, attack, and food. As a result, the head with the sense organs was in the most favorable position for observing environment and connecting with other people through facial expressions and speech.

Chewing muscles

In addition to the facial muscles, there are chewing muscles on the head, as well as muscles associated with the movements of the eyes, tongue, larynx, auditory ossicles, and swallowing.

The chewing muscles play a role in changing facial expressions. They are represented by four pairs of strong muscles located on the lateral surface of the head. What the masticatory muscles have in common is that they all attach to the lower jaw and act on the temporomandibular joint. Under the influence of these muscles, the lower jaw can rise, move to the sides and forward. The movements of the lower jaw in humans are very diverse, which is not found in other mammals. This is important not only for the act of chewing, but also for articulate speech and facial expressions.

chewing muscle
Superficially located are two chewing muscles: actually chewing and temporal. The chewing muscle starts from the zygomatic arch and is attached to the outer surface of the angle of the lower jaw. She raises her lower jaw, pressing it against her upper. The outlines of this muscle appear under the skin during chewing, and when a person is nervous and clenching his teeth with force, the state of the masticatory muscle is described as "protruding nodules." This muscle is also significantly developed in constantly chewing chewing gum subjects.

Deep chewing muscles (internal and external pterygoid) move the lower jaw up and forward, as well as to the sides. Their role is especially important when chewing food.

temporalis muscle
The fan-shaped temporal muscle is placed in the temporal fossa of the skull, is easily palpable in front of and just above the auricle and is clearly visible during chewing. This muscle elevates the lower jaw, putting the most pressure on the incisors, which is why it is called the biting muscle. The posterior bundles of the temporalis muscle pull the lower jaw backward. This muscle is especially strongly developed in predatory animals. At the same time, it is this muscle in humans that gives the exact setting of the lower jaw in the process of speech.

Smile to your health!

The work of facial muscles is closely related to the activity of the brain. The richness of facial expressions indicates the active state of the nervous system. There is also a feedback: the activity of certain facial muscles activates certain parts of the brain. Therefore, smile more often, laugh, enjoy life, but do not get angry or sad, even if you have reasons for it. You will feel a surge of strength, a positive attitude to current affairs, a good attitude towards others.