The face in this lab we are going to talk about : 1- muscles of the face 2- arteries of the face 3- veins of the face 4- the Parotid gland 5- the nerve of the face layers of the face



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THE FACE

In this lab we are going to talk about :-

1- muscles of the face

2- arteries of the face

3- veins of the face

4- the Parotid gland

5- the nerve of the face

*layers of the face :-

Skin  superficial fascia ( where the muscles of facial expressions are located )  bone.

Muscles of the face

*They are not easy to be dissected.

*They originate from the posterior aspect of the skull (occipital bone) and here we call them Occipitalis .. then they extend to the anterior aspect of the skull (frontal bone) where we call them Frontalis .. then over the head .. after that extending down as Platysma.

*Note :- the muscles of the face are located around orifices to act as dilators or constrictors, but the Occipitalis, Frontalis and Platysma don't surround orifices that's why they are one sheath at each side.



*ALL originated from bone .. ALL inserted into skin .. ALL supplied by the facial nerve .. ALL show variety of motions.

They are located :-*

A- around the mouth

1- Orbicularis oris (around the mouth below the lips).

2- Buccinator.

 for the lower lip :-

3- Depressor labii inferioris.

4- Mentalis (to depress the center of the lower lip).

 for the upper lip :-

5- Levator labii superioris.

 for the angle :-

6- Depressor anguli oris.

7- Zygomaticus major.

8- Zygomaticus minor.

9- Risorius.

B- around the nose :-

Nasalis   one of them is constrictor and the other is dilator.

We can recognize them in tiredness or sickness.

C- around the eye :-

Orbicularis oculi which is separated into 3 parts :-

1- Orbital part (the outer most).

2- Palpebral part (below the eyelids).

3- Lacrimal part (bringing the tears from lateral to medial).

Arteries of the face

-- i --

Aorta  Common carotid artery  Internal & External carotid arteries  the external gives 8 branches one of them is the FACIAL ARTERY.

The Facial artery is the major blood supply of the face.

Its course :- branches from the External carotid artery ,, passes deep to the Submandibular gland ,, then to the lower border of the mandible ,, then anterior to the Masseter muscle ,, after that passing tortuous anterior and deep to its twin the Facial vein ,, then ends at the medial angle of the eye as Angular artery.

In its way it gives branches to the face :-

1- Inferior labial artery …… 2- Superior labial artery …… 3- Lateral nasal artery …… 4- Angular artery



-- ii --

The External artery is terminated into 2 parts  Maxillary

Superficial temporal

The Superficial temporal gives the TRANSVERSE FACIAL ARTERY.

The Transverse facial artery goes parallel to the Zygomatic arch and the Parotid duct .. and it's designed to supply the Parotid duct.

Veins of the face

The Superficial temporal artery passes next to the SUPERFICIAL TEMPORAL VEIN.

This vein unites with the Maxillary vein to form the Retromandibular vein and this union happens within the Parotid gland, then it descends down, normally divided into Anterior and Posterior divisions.

FACIAL VEIN

Starts at the medial angle of the eye as an Angular vein by the union of the Supraorbital vein laterally & Supratrochlear vein medially .. then continues to the lateral side of the face .. descending down external to the Masseter muscle to the lower border of the mandible .. then superficial to the Submandibular gland .. then unites with the anterior division of the Retromandibular vein to drain into the Internal Jugular vein.



The Parotid gland

There are 3 salivary glands :-

1- Sublingual  most anterior  mucus secretion.

2- Submandibular  middle  mucus + serous secretion.

3- Parotid  most posterior  serous secretion.

*All are originated from the mouth cavity.

*The Parotid gland is the largest .. it's triangular in shape .. between the ramus of the mandible and the Sternocleidomastoid muscle .. with its base external and apex internal.

*To set its location we need 3 points :-

Angle of the mandible (inf) ,, Mastoid process (post) ,, Midpoint of the Zygomatic arch (ant).

*It's covered by 2 capsules ,, one from the deep fascia of the neck (cervical fascia) and its own fibrous capsule.

*Contents:- VANL ( Retromandibular vein , External carotid artery , Facial nerve , Parotid lymph nodes ).

*Relations of the parotid gland :-

Anteriorly   MBM   masseter muscle , ramus of mandible , medial pterygoid.

Posteriorly   mastoid process , sternocleidomastoid, digastrics.

*Parotid duct :- extending from anterior aspect of parotid gland, crossing the external surface of masseter muscle, then passing through the buccal pad of fat to reach the oral cavity, and it opens opposite the upper second molar because its origin is from there.

*It's about 5 cm in length .. parallel to the zygomatic arch and the transverse facial artery and the buccal branch of the facial nerve .. supplied by the transverse facial artery.



The nerve of the face

The FACIAL NERVE.

The internal of the skull is called Cranial cavity, the cranial cavity is like a stair of 3 steps, 1 is shallow (anterior cranial fossa), 1 is intermediate (middle cranial fossa), 1 is deep (posterior cranial fossa).

Each fossa has foramens for Cranial nerves, that are 12 in number emerging through these foramens from anterior to posterior in sequence (1 – 12).

The 7th cranial nerve (facial nerve) leaves the cavity through the first foramen in the posterior cranial fossa which is called Internal Auditory Meatus (Internal Auditory Foramen), that transmits the 7th,8th,9th cranial nerves.

Then this 7th cranial nerve exits the skull through the stylomastoid foramen to be superficial .. then it inters the parotid gland .. there it divides into 5 branches :- Temporal, Zygomatic, Buccal, Mandibular, Cirvical.

This sheet is to all of you :D

Specially my sisters :- GhaydaAa H, Yasmin b, Yasmine ch, Ghidaa m, Hala r, Raghad a, Eman th, Eman n, Rawan h, Zain d, Afaf h.



Yours

Sally A-J ;)


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