Lecture: 2 Head and neck Dr. Omar Riadh
4-10-2017
Sensory innervations of the face:
By trigeminal nerve (5th cranial nerve).1-Ophthalmic division of trigeminal nerve:-
Supraorbital nerve.
Supratrochlear nerve.
Palpebral branch of the lacrimal nerve supplies the lateral part of the upper eyelid.
Infratrochlear branch of nasociliary emerges from the orbit at the lower medial angle of the eye. It supplies the medial part of the eyelids and the root of the nose.
External nasal nerve: this is branch of anterior ethmoidal nerve which arises from the nasociliary nerve in the orbit. It emerges between the nasal bone and the lateral nasal cartilage and supplies the skin of the lower half of the dorsum of the nose.
2-Maxillary division of trigeminal nerve:-
Supplies the skin inferior and lateral to the eye by three branches:Infraorbital nerve:- it is terminal branch of maxillary nerve emerge through the infraorbital foramen supplies the skin and mucus membrane of the upper lip, lower eyelid and the skin between them and the side of the nose through labial, palpebral and nasal branches respectively.
Zygomaticofacial nerve:- passes through Zygomaticofacial foramen in the zygomatic bone, it supplies the skin over the bony part of the cheek.
Zygomaticotemporal nerve:- it pierce the zygomatic bone and supplies the skin over the anterior part of the temple.
3-Mandibular division of trigeminal nerve:
Auriculotemporal nerve:-Buccal nerve:- it appears in the cheek on the lowest part of buccinator muscle, it supplies the skin over buccinator muscle and underlying mucus membrane.
Mental nerve:- appear through the mental foramen from the inferior alveolar nerve, it supplies the skin and mucus membrane of the lower lip and skin over the mandible.
Bloob supply of the face:-
Arterial supply of the face.
1-Facial artery:-
arises from the external carotid artery runs anteriorly grooving the submandibular salivary gland and then it reaches the lower border of mandible to enter the face just anterior to the masseter muscle. This artery is tortuous to allow free movements of the head, it runs in the face up to the medial angle of the eye to becomes the angular artery.
--branches of facial artery on the neck:-
a- Tonsillar artery which runs upward to the tonsil.
b- Ascending palatine artery which supplies the palate and part of the pharynx.
c- Glandular artery to the submandibular salivary gland.
Submental artery.
--branches of facial artery on the face:-
a- Inferior labial: to the lower lip and mandible.
b- Superior labial: to the upper lip and nasal septum.
External nasal (lateral nasal).
2-Superficial temporal artery:-
3-Transverse facial artery:-
It is branch of superficial temporal artery, lies transversely crosses the cheek below the zygoma.
4-Infraorbital artery:-
Passes through the infraorbital foramen, it is one of the terminal branch of maxillary artery. It supplies the lower eyelid, lacrimal sac, side of the nose and the upper lip.
5-Mental artery:-
Appears through the mental foramen as a terminal branch of inferior alveolar artery(which is branch of maxillary artery) it supplies the region of the chin.
6-Buccal artery:-
It is branch of maxillary artery, emerges behind the ramus of the mandible, it passes with the buccal nerve and vein supplies buccinators muscle and the skin and mucus membrane of the cheek.
Venous drainage of the face:-
By facial vein which forms by the union of the supraorbital and supratrochlear veins at the medial angle of mandible, it is connected to the superior ophthalmic vein through the supraorbital fissure, and by means of superior ophthalmic vein the facial vein connected to the cavernous sinus, this connection is of great clinical important for spreading of infection from the face to the cavernous sinus.
The facial vein descends behind the facial artery to the lower margin of the body of mandible, it crosses superficial to the submandibular salivary gland and it is joined by the anterior division of retromandibular vein, it end by draining to internal jugular vein.
Tributaries:-
The facial vein receives tributaries corresponding to the branches of the facial artery, it is joined to pterygoid venous plexus by the deep facial vein and to the cavernous sinus by the superior ophthalmic vein. The transverse facial vein joins the superficial temporal vein within the parotid gland.
Lymphatic drainage of the face;-
The forehead and anterior part of the face drain to the submandibular lymph nodes.Lateral part of the face drains to pre-auricular lymph nodes.
The chin, central part of the face, and the lower lip drain to submental lymph nodes
Facial nerve:-
It is 7th cranial nerve, enters the temporal bone through the internal acoustic meatus then emerges from the stylomastoid foramen giving posterior auricular nerve to occipital bellies of occipitofrontalis muscle, also gives nerve to posterior belly of digastric and stylohyoid muscles. then the facial nerve enters anteriorly through the parotid gland between its deep and superficial lobes, in the gland it is divided into temporofacial and cervicofacial division. This nerve is:Motor:- to all muscles of facial expression, posterior belly of digastrics, stylohyoid and stapedius muscle.
Sensory (special sensation) taste fibers for anterior 2/3 of the tongue.
Parasympathetic; supply submandibular, sublingual, lacrimal, nasal,palatine and oral glands.
Branches of facial nerve:-
Posterior auricular nerve supplies occipital bellies of occipitofrontalis muscle and posterior auricular muscle.Nerve to posterior belly of digastrics muscle.
Nerve to stylohyoid muscle.
Temporal branches:- supply anterior and superior auricular muscles, frontal bellies of occipitofrontalis muscle and part of orbicularis oculi muscle.
Zygomatic branches:- supply orbicularis oculi and zygomatic muscles.
Buccal branch:- runs anterior with parotid duct supplies buccinators and orbicularis oris muscles.
Marginal mandibular branch:- descending along the mandible supplies the upper part of platysma and small muscles of the lower lip.
Cervical branch:- supplies platysma muscle.