Muscles Of Facial Expression

Question 1

Three groups

Answer 1

1. Orbital
2. Nasal
3. Oral

Question 2

Orbital group

Answer 2

Orbicularis oculi
- outer orbital part
- inner palpebral part

Actions: the palpebral part of the muscle performs the gentle closure of the eyelid
Whereas the orbital portion closes more forcefully

Corrugator supercilii
- located posteriorly to the obicularis oculi muscle
- originates from the superciliary arch running in a superolateral direction
Inserts into the skin of the eyebrow

Actions: it acts, draw the eyebrows together, crating vertical wrinkles on the bridge of the nose

Question 3

Nasal group

Answer 3

1. Nasalis
2. Procerus
3. Depressor Septi Nasi

Question 4

Nasalis

Answer 4

Two types of nasal muscles (transverse and alar)

Attachments- both portion originate from the maxilla
Transverse part attaches to an aponeurosis across the dorsum of the nose
Alar cartilage of the nasal skeleton

Function: transverse part compresses the nares
Alar part opens the nares

Question 5

Procerus

Answer 5

Most superior muscle of the nasal muscles.

Attachment: originates from the nasal bone inserting into the lower medial forehead

Actions: contractions of this muscle pulls the eyebrows downward to produce transverse wrinkles over the nose

Question 6

Depressor septi

Answer 6

Assists the alar part of the nasali in the opening the nostrils

Attachments: it runs from the maxilla (above the central incisor tooth) to the nasal septum

Actions: it pulls the nose inferiorly, opening the nares

Question 7

Oral Group

Answer 7

Singing, speaking, whistling

1. Orbicularis oris
2. Buccinator
3. Accessory muscles of the lip and cheek

Question 8

Orbicularis Oris

Answer 8

The fibers of the Orbicularis oris enclose the opening to the oral cavity

Attachments: arises from the maxilla and from the other muscles of the cheek and inserts into the skin and mucous membranes to the lips

Action: purses the lips

Question 9

Buccinator

Answer 9

This muscle is located between the mandible and maxilla, deep to the other muscles of the face

Attachments: it originates from the maxilla and mandible. The fibers run in an inferomedial medial direction, blending with the orbicularis oris and the skin of the lips

Actions: the buccinator pulls the cheek inwards against the teeth, preventing accumulation of food in that area

Question 10

Accessory muscles of facial expressions

Answer 10

The lower group contains 3 muscles
1. Depressor Anguli Oris
2. Depressor Labii Inferioris
3. Mentalis

The upper group contains 6 muscles
1. Risorius
2. Zygomaticus major
3. Zygomaticus minor
4. Lavator Labii Superioris
5. Levator Labii Superioris Alaeque Nasi
6. Levator Anguli Oris

Question 11

Ways on how the facial nerve can be damaged

Answer 11

Stroke, Bell’s palsy, Parotid Salivary Gland Cancer, Trauma, Surgery