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Blood supply and innervation of the maxillofacial area. Anatomy of the lower jaw, blood supply and innervation The maxillary nerve innervates

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The ophthalmic nerve (n. ophthalmicus) is the first, thinnest branch of the trigeminal nerve. It is sensitive and innervates the skin of the forehead and anterior part of the temporal and parietal regions, the upper eyelid, the bridge of the nose, as well as partially the mucous membrane of the nasal cavity, the membranes of the eyeball and the lacrimal gland (Fig. 1).

Rice. 1. Nerves of the orbit, top view. (The levator palpebrae superioris muscle and the superior rectus and superior oblique muscles of the eye have been partially removed):

1 - long ciliary nerves; 2 - short ciliary nerves; 3, 11 - lacrimal nerve; 4 - ciliary node; 5 - oculomotor root of the ciliary ganglion; 6 - additional oculomotor root of the ciliary ganglion; 7 - nasociliary root of the ciliary node; 8 - branches of the oculomotor nerve to the inferior rectus muscle of the eye; 9, 14 - abducens nerve; 10 - lower branch of the oculomotor nerve; 12 - frontal nerve; 13 - optic nerve; 15 - oculomotor nerve; 16 - trochlear nerve; 17 - branch of the cavernous sympathetic plexus; 18 - nasociliary nerve; 19 - superior branch of the oculomotor nerve; 20 - posterior ethmoidal nerve; 21 - optic nerve; 22 - anterior ethmoidal nerve; 23 - subtrochlear nerve; 24 - supraorbital nerve; 25 - supratrochlear nerve

The nerve is 2-3 mm thick, consists of 30-70 relatively small bundles and contains from 20,000 to 54,000 myelinated nerve fibers, mostly of small diameter (up to 5 microns). After originating from the trigeminal ganglion, the nerve passes through the outer wall of the cavernous sinus, where it gives off recurrent shell (tentorial) branch (r. meningeus recurrens (tentorius) to the tentorium of the cerebellum. Near the superior orbital fissure, the optic nerve divides into 3 branches: lacrimal, frontal and theoretical nerves.

1. Lacrimal nerve (n. lacrimalis) is located near the outer wall of the orbit, where it receives connecting branch with the zygomatic nerve (r. communicant cum nervo zygomatico). Provides sensitive innervation to the lacrimal gland, as well as the skin of the upper eyelid and lateral canthus.

2. The frontal nerve (p. frontalis) is the thickest branch of the optic nerve. It passes under the upper wall of the orbit and divides into two branches: supraorbital nerve(n. supraorbitalis), going through the supraorbital notch to the skin of the forehead, and supratrochlear nerve(p. supratrochlearis), emerging from the orbit at its inner wall and innervating the skin of the upper eyelid and medial corner of the eye.

3. Nasociliary nerve(n. nasociliaris) lies in the orbit at its medial wall and, under the block of the superior oblique muscle, exits the orbit in the form of a terminal branch - subtrochlear nerve(p. infratrochlearis), which innervates the lacrimal sac, conjunctiva and medial corner of the eye. Along its length, the nasociliary nerve gives off the following branches:

1) long ciliary nerves (pp. ciliares longi) to the eyeball;

2) posterior ethmoidal nerve (p. ethmoidalis posterior) to the mucous membrane of the sphenoid sinus and the posterior cells of the ethmoidal labyrinth;

3) anterior ethmoidal nerve (n. ethmoidalis anterior) to the mucous membrane of the frontal sinus and nasal cavity ( rr. nasales interni laterales et mediates) and to the skin of the tip and wing of the nose.

In addition, a connecting branch departs from the nasociliary nerve to the ciliary ganglion.

(ganglion ciliare) (Fig. 2), up to 4 mm long, lies on the lateral surface of the optic nerve, approximately on the border between the posterior and middle thirds of the length of the orbit. In the ciliary ganglion, as in other parasympathetic ganglia of the trigeminal nerve, there are parasympathetic multi-process (multipolar) nerve cells on which preganglionic fibers, forming synapses, switch to postganglionic ones. Sensitive fibers pass through the node in transit.

Rice. 2. Ciliary node (preparation by A.G. Tsybulkin). Impregnation with silver nitrate, clearing in glycerin. Uv. x12.

1 - ciliary node; 2 - branch of the oculomotor nerve to the inferior oblique muscle of the eye; 3 - short ciliary nerves; 4 - ophthalmic artery; 5 - nasociliary root of the ciliary node; 6 - accessory oculomotor roots of the ciliary ganglion; 7 - oculomotor root of the ciliary ganglion

Connecting branches in the form of its roots approach the node:

1) parasympathetic (radix parasympathica (oculomotoria) gangliiciliaris)- from the oculomotor nerve;

2) sensitive (radix sensorial (nasociliaris) ganglii ciliaris)- from the nasociliary nerve.

From the ciliary node extends from 4 to 40 short ciliary nerves (pp. ciliares breves), going inside the eyeball. They contain postganglionic parasympathetic fibers innervating the ciliary muscle, sphincter and, to a lesser extent, the pupillary dilator, as well as sensory fibers to the membranes of the eyeball. (Sympathetic fibers to the dilator muscle are described below.)

(n. maxillaries) - the second branch of the trigeminal nerve, sensitive. It has a thickness of 2.5-4.5 mm and consists of 25-70 small bundles containing from 30,000 to 80,000 myelinated nerve fibers, mostly of small diameter (up to 5 microns).

The maxillary nerve innervates the dura mater of the brain, the skin of the lower eyelid, the lateral corner of the eye, the anterior part of the temporal region, the upper part of the cheek, the wings of the nose, the skin and mucous membrane of the upper lip, the mucous membrane of the posterior and lower parts of the nasal cavity, the mucous membrane of the sphenoid sinus, the palate , teeth of the upper jaw. Upon exiting the skull through the foramen rotundum, the nerve enters the pterygopalatine fossa, passes from back to front and from the inside to the outside (Fig. 3). The length of the segment and its position in the fossa depend on the shape of the skull. In a brachycephalic skull, the length of the nerve segment in the fossa is 15-22 mm, it is located deep in the fossa - up to 5 cm from the middle of the zygomatic arch. Sometimes the nerve in the pterygopalatine fossa is covered by a bone crest. In a dolichocephalic skull, the length of the nerve section in question is 10-15 mm, it is located more superficially - up to 4 cm from the middle of the zygomatic arch.

Rice. 3. Maxillary nerve, lateral view. (The wall and contents of the orbit have been removed):

1 - lacrimal gland; 2 - zygomaticotemporal nerve; 3 - zygomaticofacial nerve; 4 - external nasal branches of the anterior ethmoidal nerve; 5 - nasal branch; 6 - infraorbital nerve; 7 - anterior superior alveolar nerves; 8 - mucous membrane of the maxillary sinus; 9 - middle superior alveolar nerve; 10—dental and gingival branches; 11 - upper dental plexus; 12—infraorbital nerve in the canal of the same name; 13 - posterior superior alveolar nerves: 14 - nodal branches to the pterygopalatine node; 15 - greater and lesser palatine nerves: 16 - pterygopalatine ganglion; 17 - nerve of the pterygoid canal; 18 - zygomatic nerve; 19 - maxillary nerve; 20 - mandibular nerve; 21 - foramen ovale; 22 - round hole; 23 - meningeal branch; 24 - trigeminal nerve; 25 - trigeminal node; 26 - optic nerve; 27 - frontal nerve; 28 - nasociliary nerve; 29 - lacrimal nerve; 30 - ciliary node

Within the pterygopalatine fossa, the maxillary nerve gives off meningeal branch (g. meningeus) to the dura mater and divides into 3 branches:

1) nodal branches to the pterygopalatine node;

2) zygomatic nerve;

3) the infraorbital nerve, which is a direct continuation of the maxillary nerve.

1. Nodal branches to the pterygopalatine ganglion (rr. ganglionares ad ganglio pterygopalatinum) (1-7 in number) depart from the maxillary nerve at a distance of 1.0-2.5 mm from the foramen rotundum and go to the pterygopalatine ganglion, giving sensory fibers to the nerves starting from the ganglion. Some nodal branches bypass the node and join its branches.

Pterygopalatine ganglion(ganglion pterygopalatinum) - formation of the parasympathetic part of the autonomic nervous system. The node is triangular in shape, 3-5 mm long, contains multipolar cells and has 3 roots:

1) sensitive - nodal branches;

2) parasympathetic - greater petrosal nerve(n. petrosus major)(branch of the intermediate nerve), contains fibers to the glands of the nasal cavity, palate, lacrimal gland;

3) sympathetic - deep petrosal nerve(n. petrosus profundus) originates from the internal carotid plexus and contains post-ganglionic sympathetic nerve fibers from the cervical ganglia. As a rule, the large and deep petrosal nerves unite to form the nerve of the pterygoid canal, which passes through the canal of the same name at the base of the pterygoid process of the sphenoid bone.

Branches extend from the node, which include secretory and vascular (parasympathetic and sympathetic) and sensory fibers (Fig. 4):

Rice. 4. Pterygopalatine ganglion (diagram):

1 - superior salivary nucleus; 2—facial nerve; 3— genu of the facial nerve; 4 - greater petrosal nerve; 5— deep petrosal nerve; 6—nerve of the pterygoid canal; 7 - maxillary nerve; 8— pterygopalatine node; 9 - posterior superior nasal branches; 10—infraorbital nerve; 11 - nasopalatine nerve; 12 - postganglionic autonomic fibers to the mucous membrane of the nasal cavity; 13 - maxillary sinus; 14 - posterior superior alveolar nerves; 15—greater and lesser palatine nerves; 16—tympanic cavity; 17— internal carotid nerve; 18— internal carotid artery; 19—superior cervical ganglion of the sympathetic trunk; 20 - autonomous nuclei of the spinal cord; 21 - sympathetic trunk; 22 - spinal cord; 23 - medulla oblongata

1) orbital branches(rr. orbitales), 2-3 thin trunks, penetrate through the inferior orbital fissure and then, together with the posterior ethmoidal nerve, go through the small openings of the sphenoid-ethmoidal suture to the mucous membrane of the posterior cells of the ethmoidal labyrinth and the sphenoid sinus;

2) posterior superior nasal branches(rr. nasales posteriores superiors)(8-14 in number) exit the pterygopalatine fossa through the sphenopalatine foramen into the nasal cavity and are divided into two groups: lateral and medial (Fig. 5). Lateral branches (rr. nasales posteriores superiores laterales)(6-10), go to the mucous membrane of the posterior sections of the superior and middle nasal concha and nasal passages, the posterior cells of the ethmoid bone, the upper surface of the choanae and the pharyngeal opening of the auditory tube. Medial branches (rr. nasales posteriores superiores mediates)(2-3), branch in the mucous membrane of the upper part of the nasal septum.

Rice. 5. Nasal branches of the pterygopalatine ganglion, view from the nasal cavity: 1 - olfactory filaments; 2, 9 - nasopalatine nerve in the incisive canal; 3 - posterior superior medial nasal branches of the pterygopalatine ganglion; 4 - posterior superior lateral nasal branches; 5 - pterygopalatine node; 6 - posterior lower nasal branches; 7 - lesser palatine nerve; 8 - greater palatine nerve; 10 - nasal branches of the anterior ethmoidal nerve

One of the medial branches is nasopalatine nerve (n. nasopalatinus)- passes between the periosteum and the mucous membrane of the septum together with the posterior artery of the nasal septum forward, to the nasal opening of the incisive canal, through which it reaches the mucous membrane of the anterior part of the palate (Fig. 6). Forms a connection with the nasal branch of the superior alveolar nerve.

Rice. 6. Sources of innervation of the palate, ventral view (soft tissues removed):

1 - nasopalatine nerve; 2 - greater palatine nerve; 3 - lesser palatine nerve; 4 - soft palate

3) palatine nerves (pp. palatine) spread from the node through the greater palatine canal, forming 3 groups of nerves:

1) greater palatine nerve (p. palatinus major)- the thickest branch, exits through the large palatine foramen onto the palate, where it splits into 3-4 branches that innervate most of the mucous membrane of the palate and its glands in the area from the canines to the soft palate;

2)minor palatine nerves (par. palatini minores) enter the oral cavity through the small palatine openings and branch in the mucous membrane of the soft palate and the region of the palatine tonsil;

3) lower posterior nasal branches (rr. nasales posteriores inferiors) They enter the greater palatine canal, leave it through small openings and, at the level of the inferior turbinate, enter the nasal cavity, innervating the mucous membrane of the inferior turbinate, middle and lower nasal passages and the maxillary sinus.

2. The zygomatic nerve (n. zygomaticus) branches off from the maxillary nerve within the pterygopalatine fossa and penetrates through the inferior orbital fissure into the orbit, where it runs along the outer wall, gives off a connecting branch to the lacrimal nerve, containing secretory parasympathetic fibers to the lacrimal gland, enters into the zygomaticoorbital foramen and inside the zygomatic bone it is divided into two branches:

1) zygomaticofacial branch(g. zygomaticofacialis) which exits through the zygomatic-facial foramen onto the anterior surface of the zygomatic bone; in the skin of the upper part of the cheek it gives off a branch to the area of the outer canthus and a connecting branch to the facial nerve;

2) zygomaticotemporal branch(g. zygomaticotemporalis), which exits the orbit through the opening of the same name in the zygomatic bone, pierces the temporalis muscle and its fascia and innervates the skin of the anterior part of the temporal and posterior part of the frontal regions.

3. Infraorbital nerve(n. infraorbitalis) is a continuation of the maxillary nerve and gets its name after the above branches depart from it. The infraorbital nerve leaves the pterygopalatine fossa through the inferior orbital fissure, passes along the lower wall of the orbit along with the vessels of the same name in the infraorbital groove (in 15% of cases there is a bone canal instead of a groove) and exits through the infraorbital foramen under the muscle that lifts the upper lip, dividing into terminal branches. The length of the infraorbital nerve is different: with brachycephaly, the nerve trunk is 20-27 mm, and with dolichocephaly - 27-32 mm. The position of the nerve in the orbit corresponds to the parasagittal plane drawn through the infraorbital foramen.

The origin of the branches can also be different: scattered, in which numerous thin nerves with many connections depart from the trunk, or main with a small number of large nerves. Along its path, the infraorbital nerve gives off the following branches:

1) superior alveolar nerves(pp. alveolares superiors) innervate the teeth and upper jaw (see Fig. 4). There are 3 groups of branches of the superior alveolar nerves:

1) posterior superior alveolar branches (rr. alveolares superiores posteriors) They branch from the infraorbital nerve, as a rule, in the pterygopalatine fossa, numbering 4-8 and located together with the vessels of the same name along the surface of the tubercle of the upper jaw. Some of the most posterior nerves go along the outer surface of the tubercle down to the alveolar process, the rest enter through the posterior superior alveolar foramina into the alveolar canals. Branching together with other superior alveolar branches, they form the nervous superior dental plexus(plexus dentalis superior), which lies in the alveolar process of the upper jaw above the apexes of the roots. The plexus is dense, broadly looped, stretched along the entire length of the alveolar process. They depart from the plexus upper gingival branches (rr. gingivales superiors) to the periodontium and periodontium in the area of the upper molars and upper dental branches (rr. dentales superiors)- to the tips of the roots of large molars, in the pulp cavity of which they branch. In addition, the posterior superior alveolar branches send thin nerves to the mucous membrane of the maxillary sinus;

2) middle superior alveolar branch (r. alveolaris superior) in the form of one or (less often) two trunks it branches off from the infraorbital nerve, most often in the pterygopalatine fossa and (less often) within the orbit, passes in one of the alveolar canals and branches in the bone canaliculi of the upper jaw as part of the superior dental plexus. It has connecting branches with the posterior and anterior superior alveolar branches. Innervates the periodontium and periodontium in the area of the upper premolars through the upper gingival branches and the upper premolars through the upper dental branches;

3) anterior superior alveolar branches (rr. alveolares superiores ateriores) arise from the infraorbital nerve in the anterior part of the orbit, which leaves through the alveolar canals, penetrating the anterior wall of the maxillary sinus, where they form part of the superior dental plexus. Upper gingival branches innervate the mucous membrane of the alveolar process and the walls of the alveoli in the area of the upper canines and incisors, upper dental branches- upper canines and incisors. The anterior superior alveolar branches send a thin nasal branch to the mucous membrane of the anterior floor of the nasal cavity;

2) lower branches of the eyelids(rr. palpebrales inferiors) they branch from the infraorbital nerve as they exit the infraorbital foramen, penetrate through the levator labii superioris muscle, and, branching, innervate the skin of the lower eyelid;

3) external nasal branches(rr. nasales superiors) innervate the skin in the area of the wing of the nose;

4) internal nasal branches(rr. nasales interni) approach the mucous membrane of the vestibule of the nasal cavity;

5) superior labial branches(rr. labiates superiors)(3-4 in number) go down between the upper jaw and the muscle that lifts the upper lip; innervate the skin and mucous membrane of the upper lip to the corner of the mouth.

All of the listed external branches of the infraorbital nerve form connections with the branches of the facial nerve.

Human anatomy S.S. Mikhailov, A.V. Chukbar, A.G. Tsybulkin

The anatomical structure of human jaws explains the peculiarities of their functioning. To understand the principles of the structure of the maxillofacial region, you should pay attention not only to those fibers that are responsible for transmitting impulses, but also to the blood supply. Innervation of the maxillofacial region is an important process, and it is worth discussing in detail.

Features of the structure of the upper and lower jaw

The human facial skeleton includes two jaws - lower and upper. A number of functions depend on their formation - breathing, swallowing, chewing food. Thanks to the jaws, a person’s profile is formed, they determine his attractiveness and aesthetics, and are required for the formation of cavities where the sensory organs are located.

Types of nerves of the maxillofacial region and their functions

The trigeminal nerve and its branches innervate the maxillofacial region - it is located in the cranial cavity. The mandibular nerve (it gives rise to the nerves of the lower jaw), the maxillary nerve and the orbital nerve depart from it. The facial nerve is responsible for transmitting impulses to the facial muscles. If one of its branches is damaged, it will result in distorted expression or permanent paralysis of the patient's face.

Maxillary

The maxillary nerve is one of the branches of the trigeminal nerve. There is a circular opening in the skull through which the maxillary nerve exits the cranial cavity. Branches arise from the maxillary nerve. If we consider the approximate diagram of their placement, it looks like this in the order of movement of the maxillary nerve:

Mandibular

Sensory and motor fibers make up the trunk of the mandibular nerve. This nerve of the lower jaw is characterized by branching into the anterior and posterior lobes at the exit from the cranial cavity. The structure of the branches is not the same - in the first case, most of them are fibers of the sensory type, and in the second - motor fibers. This category of fibers is the basis of the mylohyoid nerve. Its main branches:

Orbital

The ophthalmic nerve is the 3rd branch of the trigeminal nerve. Innervation of the teeth or jaw is not one of its functions. As the name suggests, it refers to the transmission of impulses to the organs of vision and nearby tissues. It is examined when a patient develops a malignant neoplasm or neuralgia.

Sublingual

The hypoglossal nerve has a motor nucleus, its function is to innervate the muscles of the tongue. The branch consists of 10 - 15 fibers, each of them goes to a separate muscle. The nerve takes part in the implementation of the processes of chewing food, swallowing, licking, sucking - it is one of the parts of the corresponding reflex arc.

Pathologies of the trigeminal nerve

When mentioning pathologies of the trigeminal nerve, the first thing that comes to mind is neuralgia or neuritis. However, other lesions may also occur.

Both itself and one/several of its branches can be damaged. For example, sometimes only the maxillary nerve is affected. Pathological processes completely or partially disrupt the innervation of the maxillofacial area. The main operational problems include:

hyperesthesia;
anesthesia;
impaired sensitivity of the jaws and facial area;
trigeminal neuralgia (symptomatic or idiopathic);
damage to the sensory fibers of the trigeminal nerve nucleus;
Gradenigo syndrome.

Features of treatment

A common pathology affecting the trigeminal nerve is neuralgia. Neuritis, tooth extraction, surgical intervention in the treatment of teeth or sinuses, massive facial trauma - these causes provoke damage to the maxillary nerve and one (sometimes several) of its branches. The main symptom of the disease is severe acute pain, therefore, in the complex of therapy, an important place is given to its relief.

Treatment of neuralgia
Conservative	Physiotherapeutic	Surgical
Painkillers (Novocaine) – for prolonged and intense pain syndrome	Massage (used with caution only as prescribed by a doctor after a comprehensive examination)	Vascular decompression (pathological impulses are eliminated by installing a special protector)
Antidepressants (Ampitriline)	Pulse currents (impact is carried out pointwise, on areas of the patient’s face)	Pain fibers are destroyed using an inflated balloon (balloon microcompression)
Complex therapy (Pantogam, Baclofen)	Ionic galvanization	Rhizotomy (represents the destruction of pain fibers with an electrode or glycerin)
Anticonvulsants (Finlepsin, Difenin)	Laser or acupuncture	Branch blockade (novocaine, 80% ethyl alcohol)
Anticonvulsants, analgesics (Carbamazepine) - a group of drugs that form the basis of the treatment of neuralgia	Electrophoresis
	Ultrasound therapy

Blood supply and innervation

The largest vessel responsible for the blood supply to the area under consideration is the maxillary artery. The function of blood supply to the lower jaw (in particular, its chin region) is performed by branches of the lingual artery. The branches and body of this part of the skull are supplied with blood through a complex of vessels and their processes. This feature of the blood supply is important to take into account when performing surgical operations. This is also true for tooth extraction.

The blood supply to the lower row of teeth is carried out by branches of the inferior alveolar artery. The blood supply to the teeth of the upper row and the alveolar process is carried out by the branches of the maxillary artery. The maxillofacial region is characterized by good lymphatic drainage due to the developed lymphatic network.

Preventive measures

It should be borne in mind that not a single set of preventive measures provides an absolute guarantee that the person performing them will never encounter pathologies of the nerves of the maxillofacial area.

a balanced diet, giving up bad habits, a good night's rest, hardening - this allows you to provide the body with a complex of necessary vitamins and microelements, reduce the likelihood of emotional overload, strengthen the immune system and limit the influence of harmful substances;
timely and complete treatment of dental diseases, sinusitis, facial injuries;
promptly seek medical help with minimal discomfort in the trigeminal nerve area;
undergoing an annual preventive examination;
It is advisable not to be in drafts and, if possible, not to become overcooled.

The head and neck are supplied with blood mainly by common carotid arteries. The common carotid artery itself, as a rule, does not give branches to individual organs, but usually in the area of the carotid triangle it is divided into two terminal branches: the internal and external carotid arteries.

External carotid artery is the main and almost the only artery involved in the blood supply to the oral cavity. It, in turn, is divided into two branches: the maxillary and the superficial temporal. The lingual, facial and superior thyroid arteries also depart from the anterior surface of the external carotid artery.

Blood supply to teeth carried out by the branches of the maxillary artery. The anterior and posterior superior alveolar arteries approach the teeth of the upper jaw, from which smaller branches extend to the teeth, gums and socket walls.

To the teeth of the lower jaw The inferior alveolar artery branches off from the maxillary artery and runs in the mandibular canal, where it gives off dental and interalveolar branches. Dental arteries enter the root canals through the apical foramina and branch into the dental pulp. The veins of the same name accompanying the arteries carry out the outflow of blood from the teeth into the pterygoid venous plexus.

Oral organs receive motor, sensory, gustatory and secretory nerve fibers.

Of 12 pairs of cranial nerves The trigeminal, facial, glossopharyngeal, vagus and hypoglossal nerves participate in the innervation of the organs of the oral cavity and pharynx. All five nerves that innervate the walls and organs of the oral cavity have nuclei in the brain stem. These nuclei are divided into motor, sensory and autonomic.

Trigeminal nerve mixed in composition: contains sensory and motor fibers. It innervates the muscles of mastication, the skin of the face and the anterior part of the brain, as well as the mucous membrane and glands of the oral cavity. It has three main branches - the orbital, maxillary and mandibular nerves.

Motor fibers of the facial nerve(intermediate-facial) innervate mainly the facial muscles and partially the muscles of the floor of the mouth. The intermediate nerve leaves the brain as an independent trunk, contains autonomic and taste fibers, and joins the facial nerve inside the pyramid of the temporal bone.

Glossopharyngeal nerve innervates the mucous membrane of the posterior third of the tongue, palatine arches, pharynx, and parotid gland. It also contains taste fibers from the posterior third of the tongue.
Vagus nerve takes part in the innervation of the muscles of the soft palate. It forms connecting branches with the glossopharyngeal and facial nerves.
Hypoglossal nerve innervates only the muscles of the tongue, both its own and the skeletal muscles intertwined with it.

Teeth are innervated branches of the trigeminal nerve and branches arising from the autonomic ganglia. The teeth of the upper jaw are innervated by the superior alveolar nerves: anterior - by the anterior branches, premolars - by the middle branch, molars - by the posterior branches. All branches of the superior alveolar nerves form the superior dental plexus, from which the superior dental branches extend to the teeth and the superior gingival branches to the gums and walls of the dental sockets.

Teeth of the lower jaw innervated by the inferior alveolar nerve, the branches of which form the anterior dental plexus. It gives off the lower dental branches to the teeth and the lower gingival branches to the gums and walls of the sockets. Dental nerves, together with blood vessels, pass through the apical foramen into the tooth cavity, branching into the pulp tissues.

The organs of the oral cavity receive innervation from motor, sensory, and autonomic (sympathetic and parasympathetic) nerves. The sensory nerves innervating the skin of the face, soft tissues and organs of the oral cavity, jaw, include the trigeminal, glossopharyngeal, vagus nerves and branches coming from the cervical plexus (greater auricular and lesser occipital nerves). In the facial area, along the branches of the trigeminal nerve, there are five autonomic nerve nodes: 1) ciliary (gangl. ciliare), 2) pterygopalatine (gangl. pterigopalatinum), 3) auricular (gangl. oticum), 4) submandibular (gangl. submandibulare), 5) sublingual (gangl. sublinguale). The ciliary ganglion is connected to the first branch of the trigeminal nerve, the pterygopalatine ganglion is connected to the second branch, and the auricular, submandibular and sublingual nerve ganglia are connected to the third branch. Sympathetic nerves to the tissues and organs of the face come from the superior cervical sympathetic ganglion.

Trigeminal nerve(n. trigeminus) mixed. It contains motor, sensory and parasympathetic nerve fibers. The organs of the oral cavity receive sensory innervation mainly from the trigeminal nerve (Fig. 5.5). Three large branches depart from the trigeminal ganglion:

1) optic nerve, 2) maxillary nerve and 3) mandibular nerve.

Ocular nerve in (n. ophthalmicus) sensitive, does not participate in the innervation of the jaws and tissues of the oral cavity.

(n. maxillaris) sensitive, exits from the cranial cavity through the round opening (foramen rotundum) into the pterygopalatine fossa (fossa pterigopalatina), where it gives off a number of branches (Fig. 5.6).

The infraorbital nerve (n. infraorbitalis) is a continuation of the maxillary nerve and gets its name after the departure from the last zygomatic and pterygopalatine nerves. From the pterygopalatine fossa through the inferior orbital fissure it enters the orbit, where it lies in the infraorbital groove (sulcus infraorbitalis) and through the infraorbital foramen (foramen infraorbitalis) it leaves the orbit, dividing into terminal branches. The superior labial branches form the “lesser crow's foot” (pes anserinus minor), innervate the skin and mucous membrane of the upper lip, lower lip, infraorbital region, wing of the nose and the skin of the nasal septum.

In the pterygopalatine fossa, the posterior superior alveolar branches (rami alveolares superiores posteriores) extend from 4 to 8 from the infraorbital nerve. A minority of them are not included in the thickness of the bone tissue and spread down the outer surface of the tubercle of the upper jaw towards the alveolar process. They end in the periosteum of the upper jaw, adjacent to the alveolar process, the mucous membrane of the cheek and gums on the vestibular side at the level of the large and small molars. Most of the posterior superior alveolar branches penetrate through the foramina alveolaria posteriores onto the outer surface of the upper jaw and enter its bone canaliculi. These nerves innervate the tubercle of the maxilla, the mucous membrane of the maxillary sinus, the upper molars, the mucous membrane and periosteum of the alveolar process within these teeth. The posterior superior alveolar branches take part in the formation of the posterior section of the superior dental plexus.

In the posterior part of the infraorbital groove, the middle superior alveolar branch (ramus alveolaris superior medius) departs from the infraorbital nerve. The middle superior alveolar branch is formed at the posterior edge or in the region of the posterior third of the infraorbital canal. Before entering the anterior wall of the maxilla, this nerve often divides into two more branches. The middle superior alveolar branch runs through the anterior wall of the maxilla and branches in the alveolar process. This branch takes part in the formation of the middle section of the upper dental plexus, has anastomoses with the anterior and posterior upper alveolar branches, innervates the upper small molars, the mucous membrane of the alveolar process and the gums on the vestibular side in the area of these teeth. The middle superior alveolar ramus is sometimes absent, so the premolars may receive sensory nerve fibers from the superior posterior alveolar nerves.

In the anterior section of the infraorbital canal, the anterior superior alveolar branches (rami alveolares superiores anteriores), 1-3 in total, depart from the infraorbital nerve. These branches may, however, arise from the infraorbital nerve along the entire length of the infraorbital canal or groove, at the level of the infraorbital foramen. The anterior alveolar nerves can exit in the same canal (infraorbital) with the infraorbital nerve or be located in a separate bone canal. Passing through the thickness of the anterior wall of the upper jaw, medial to the middle superior alveolar branch, the anterior superior alveolar branches take part in the formation of the anterior section of the superior dental plexus. They innervate the incisors and canines, the mucous membrane and periosteum of the alveolar process and the mucous membrane of the gums on the vestibular side in the area of these teeth. The nasal branch departs from the anterior superior alveolar branches to the mucous membrane of the anterior floor of the nose, which anasgomosizes with the nasopalatine nerve.

The posterior, middle and anterior superior alveolar branches, passing through the thickness of the walls of the upper jaw, anastomose with each other, form the superior dental plexus (plexus dentalis superior), which anastomoses with the same plexus of the other side. The plexus is located in the thickness of the alveolar process of the upper jaw along its entire length above the apices of the roots of the teeth, as well as in the upper parts of it in close proximity to the mucous membrane of the maxillary sinus.

A number of branches arise from the superior dental plexus:

dental branches (rami dentales) to the dental pulp;
periodontal and gingival branches (rami periodontales et rami gingivales), innervating the periodontium of teeth and gum tissue;
interalveolar branches to the interalveolar septa, from where branches extend to the periodontium of the teeth and the periosteum of the jaw;
to the mucous membrane and bone walls of the maxillary sinus.

Branches from the posterior section of the dental plexus branch in the area of the large molars, from the middle section - in the area of the small molars, from the anterior - in the area of the incisors and canines.

From the infraorbital nerve at the exit from the infraorbital foramen depart:

the lower branches of the eyelids (rami palpebrales inferiores), which innervate the skin of the lower eyelid;
external nasal branches (rami nasales externi), innervating the skin of the wing of the nose;
internal nasal branches (rami nasales interni), innervating the mucous membrane of the nasal vestibule;
superior labial branches (rami labiales superiores), innervating the skin and mucous membrane of the upper lip to the corner of the mouth.

The last 4 groups of branches have connections with the branches of the facial nerve.

In the pterygopalatine fossa, the zygomatic nerve (n. zygomaticus) departs from the maxillary nerve, which penetrates the orbit through the inferior orbital fissure and is divided into two branches - the zygomaticofacial (ramus zygomaticofacial) and the zygomaticotemporal (ramus zygomaticotemporal). These branches enter the thickness of the zygomatic bone through the zygomaticoorbital foramen, and then leave it through the corresponding openings of the same name, branching in the skin of the zygomatic region, the upper part of the cheek and the outer corner of the eye, the anterior part of the temporal and posterior part of the frontal regions. The zygomatic nerve has connections with the facial and lacrimal nerves.

In the pterygopalatine fossa, the pterygopalatine nerves (nn. pterigopalatini) depart from the lower surface of the maxillary nerve. They go to the pterygopalatine ganglion, giving sensory fibers to the nerves starting from it. A significant part of the fibers passes along the outer surface of the unit without interruption in it. The pterygopalatine ganglion (gangl. pterigo-palatinum) is a formation of the autonomic nervous system (Fig. 5.7). It receives parasympathetic fibers from the ganglion geniculi of the facial nerve in the form of the large stony nerve (n. petrosus major), sympathetic fibers from the sympathetic plexus of the internal carotid artery in the form of the deep petrosal nerve (n. petrosus profundus). Passing along the pterygoid canal, the large and deep petrosal nerves unite and form the nerve of the pterygoid canal. Branches depart from the node, including secretory (parasympathetic and sympathetic) and sensory fibers: orbital (rami orbitales), posterior superior and inferior nasal branches (rami nasales posteriores superiores, rami nasales posteriores inferiores), palatine nerves (nn. palatini). The orbital branches branch in the mucous membrane of the posterior cells of the ethmoid labyrinth and the sphenoid sinus.

The posterior superior nasal branches (rami nasales posteriores superiores) enter the nasal cavity from the pterygopalatine fossa through the foramen sphenopalatinum and are divided into 2 groups: lateral and medial. The lateral branches (rami laterales) branch in the mucous membrane of the posterior sections of the superior and middle nasal concha and nasal passages, the posterior cells of the ethmoid sinus, the upper surface of the choanae and the pharyngeal opening of the auditory tube. The medial branches (rami mediales) branch in the mucous membrane of the upper part of the nasal septum. The largest of them - the nasopalatine nerve (p. nasopalatine) - runs between the periosteum and the mucous membrane of the nasal septum down and forward to the incisive canal, where it anastomoses with the nerve of the same name on the other side and through the incisive opening enters the hard palate (Fig. 5.8). Passing along the incisive canal, sometimes before entering it, the nerve gives a series of anastomoses to the anterior section of the upper dental plexus. The nasopalatine nerve innervates a triangular section of the mucous membrane of the hard palate in its anterior section between the canines.

The lower posterior lateral nasal branches (rami nasales posteriores inferiores laterales) enter the canalis palatinus major and exit through small openings. They penetrate the nasal cavity, innervating the mucous membranes of the inferior turbinate, lower and middle nasal passages and the maxillary sinus.

The palatine nerves (nn. palatini) go from the pterygopalatine ganglion through the canalis palatinus major and form 3 groups of nerves.

The greater palatine nerve (n. palatinus major) is the largest branch, enters the hard palate through the foramen palatinus major, where it innervates the posterior and middle sections of the mucous membrane of the hard palate (up to the canine), minor salivary glands, the mucous membrane of the gums on the palatine side, partially mucous membrane of the soft palate.

The lesser palatine nerves (nn. palatini minores) exit through the lesser palatine foramina. They branch in the mucous membrane of the soft palate and palatine tonsil. They innervate the muscle that lifts the soft palate (m. levator veli palatini). Motor fibers go from the facialis point through the petrosus major point.

(n. mandibularis) mixed (Fig. 5.9). Contains sensory and motor fibers. It exits the cranial cavity through the foramen ovale and divides into a number of branches in the infratemporal fossa. Some of the latter are associated with nodes of the autonomic nervous system: with the internal pterygoid and auriculotemporal nerves - the ear node (gangl. oticum), with the lingual nerve - the submandibular node (gangl. submandibulare). The sublingual ganglion (gangl. sublinguale) is connected to the hypoglossal nerve (n. sublingualis), a branch of the lingual nerve. From these nodes postganglionic parasympathetic secretory fibers go to the salivary glands and gustatory fibers to the taste buds of the tongue. Sensory branches make up most of the mandibular nerve. Motor fibers from the third branch of the trigeminal nerve go to the muscles that lift the mandible (muscles of mastication).

The chewing nerve (n. massetericus) is predominantly motor. Often it has a common origin with other nerves of the masticatory muscles. Having separated from the main trunk, the masticatory nerve runs outward under the superior head of the lateral pterygoid muscle, then along its outer surface. Through the notch of the lower jaw it enters the masticatory muscle, heading towards its anterior corner. Branches extend from the main trunk to muscle bundles. Before entering the muscle, the masseteric nerve gives off a thin sensory branch to the temporomandibular joint.

The anterior deep temporal nerve (n. temporalis profundus anterior), separated along with the buccal nerve, passes outward over the upper edge of the lateral pterygoid muscle. Having gone around the infratemporal crest, it lies on the outer surface of the scales of the temporal bone. It branches in the anterior section of the temporal muscle, entering it from the inner surface.

The middle deep temporal nerve (n. temporalis profundus medius) is unstable. Separating posteriorly from the anterior deep temporal nerve, it passes under the crista infratemporalis to the inner surface of the temporal muscle and branches in its middle section.

The posterior deep temporal nerve (n. temporalis profundus posterior) begins posterior to the middle or anterior deep temporal nerve. Rounding the infratemporal crest, it penetrates under the lateral pterygoid muscle onto the inner surface of the posterior section of the temporal muscle, innervating it.

All deep temporal nerves separate (give off) from the outer surface of the mandibular nerve.

The lateral pterygoid nerve (n. pterigoideus lateralis) usually arises along the same trunk as the buccal nerve. Sometimes it begins independently from the outer surface of the mandibular nerve and enters the lateral pterygoid muscle from above and from its inner surface.

The medial pterygoid nerve (n. pterygoidues medians) is predominantly motor. It starts from the inner surface of the mandibular nerve, goes forward and down to the inner surface of the medial pterygoid muscle, which it enters near its upper edge. The nerve of the tensor velum palatini muscle and the nerve of the tensor tympani muscle arise from the medial pterygoid nerve.

The mylohyoid nerve (n. mylochyoideus) departs from the inferior alveolar nerve before the latter enters the foramen mandibulare, goes to the mylohyoid and digastric muscles (to the anterior abdomen).

The following sensory nerves arise from the mandibular nerve.

1. The buccal nerve (n. buccalis) is directed downward, forward and outward. Separating below the foramen ovale from the main trunk, it passes between the two heads of the lateral pterygoid muscle to the inner surface of the temporal muscle. Then, passing at the anterior edge of the coronoid process, at the level of its base it spreads along the outer surface of the buccal muscle to the corner of the mouth. It branches in the skin and mucous membrane of the cheek, in the skin of the corner of the mouth. Gives branches to the area of the mucous membrane of the gums of the lower jaw (between the second small and second large molars). Has anastomoses with the facial nerve and ear ganglion. It should be remembered that there are two types of branching of the buccal nerve - scattered and main. In the first type, its innervation zone extends from the wing of the nose to the middle of the lower lip, i.e. The buccal nerve is distributed in the zone of innervation of the mental and infraorbital nerves. This nerve does not always innervate the mucous membrane of the alveolar process on the vestibular side. The buccal nerve is not located together with the lingual and lower alveolar nerves in the region of the mandibular ridge (torus mandibularis), but passes anterior to the temporal muscle in the tissue of the buccal region at a distance of 22 mm from the lingual and 27 mm from the lower alveolar nerves. This may explain the inconsistent switching off of the buccal nerve during torusal anesthesia, when the optimal amount of anesthetic (2-3 ml) is administered (P.M. Egorov).

2. The auriculotemporal nerve (n. auriculotemporalis) contains sensory and parasympathetic fibers. Separating under the foramen ovale, it runs backward along the inner surface of the lateral pterygoid muscle, then goes outward, bending around the neck of the condylar process of the mandible from behind. After this, it goes upward, penetrating through the parotid salivary gland, approaches the skin of the temporal region, branching into terminal branches.

3. The lingual nerve (n. lingualis) begins near the foramen ovale at the same level as the inferior alveolar nerve and is located between the pterygoid muscles in front of it. At the upper edge of the medial pterygoid muscle, the tympanic chord (chorda tympani) joins the lingual nerve, which contains secretory fibers going to the sublingual and submandibular nodes, and taste fibers going to the papillae of the tongue. Next, the lingual nerve is located between the inner surface of the branch of the lower jaw and the internal pterygoid muscle. Anterior to the anterior edge of this muscle, the lingual nerve runs above the submandibular salivary gland along the outer surface of the hyoglossus muscle, bends around the outside and below the excretory duct of the submandibular salivary gland and is woven into the lateral surface of the tongue. In the mouth, the lingual nerve gives off a number of branches (branches of the isthmus of the pharynx, hypoglossal nerve, lingual branches) innervating the mucous membranes of the pharynx, sublingual region, mucous membrane of the gums of the lower jaw on the lingual side, the anterior two-thirds of the tongue, sublingual salivary gland, and papillae of the tongue.

4. Lower alveolar nerve (n. alveolaris inferior) mixed. This is the largest branch of the mandibular nerve. Its trunk lies on the inner surface of the external pterygoid muscle behind and lateral to the lingual nerve. Passes in the interpterygoid tissue space formed by the lateral pterygoid muscle on the outside and the medial pterygoid muscle, i.e. in the pterygomaxillary cellular space. Through the opening of the lower jaw (foramen mandibulae) it enters the canal of the lower jaw (canalis mandibulae). In it, the inferior alveolar nerve gives off branches, which, anastomosing among themselves, form the inferior dental plexus (plexus dentalis inferior). The lower dental and gingival branches extend from it to the teeth, the mucous membrane of the alveolar part and the gums of the lower jaw on the vestibular side. Sometimes the lower dental and gingival branches arise directly from this nerve. At the level of small molars, a large branch departs from the lower alveolar nerve - the mental nerve (n. mentalis), which exits through the mental foramen and innervates the skin and mucous membrane of the lower lip, the skin of the chin. The section of the inferior alveolar nerve, located in the thickness of the bone in the area of the canine and incisors, after the departure of the mental nerve, is called the incisive branch of the inferior alveolar nerve (ramus incisivus nervi alveolaris inferioris). Innervates the canine and incisors, the mucous membrane of the alveolar part and the gums on the vestibular side in the area of these teeth. Anastomoses with the branch of the same name on the opposite side in the midline area. From the lower alveolar nerve, before it enters the canal of the lower jaw, a motor branch departs - the mylohyoid nerve (n. mylochyoideus).