Facial Muscles and Muscles of Mastication

Question 1

What do the facial muscles attach to in general?

Answer 1

Originate from bone or fascia Insert into skin Located in subcutaneous tissue

Question 2

What are the facial muscles innervated by?

Answer 2

Facial nerve

Question 3

General movements of the orbital group?

Answer 3

Control movement of the eyelid and so protect the cornea from damage

Question 4

Name the muscles of the orbital group

Answer 4

Orbicularis oculi

Corrugator supercillii

Question 5

Movements of the orbiculares oculi?

Answer 5

Inner palpebral part closes the eye gently Outer orbital part does it more forcefully

Question 6

Actions of the corrugator supercillii?

Answer 6

Draws eyebrows together

Question 7

Where is the corrugator supercillii located in relation to the orbicularis oculi? Desribe it.

Answer 7

Smaller

Posterior to the OO

Inserts into the skin of the eyebrow

Question 8

Damage to the facial nerve results in orbitals beings paralysed. What can this cause?

Answer 8

Eye cannot close, cornea dries out, exposure keratitis Lower lid droops - ‘ectropion’ - lacrimal fluid pools in lower lid and isn’t spread across surface of the eye. Failure to remove debris so get ulceration of the corneal surface

Question 9

How to test for facial nerve palsy?

Answer 9

Raise eyebrows Close eyes

Question 10

Name the facial muscles of the nasal group

Answer 10

Nasalis Procerus Depressor septi nasi

Question 11

Talk about the nasalis

Answer 11

Largest of the nasal group Split in two parts - transverse and alar Transverse compresses nares, alar opens them

Question 12

Action of the procerus?

Answer 12

Most superior

Pulls eyebrows down

Question 13

Action of the depressor septi nasi?

Answer 13

Pulls nose inferiorly, opening nares

Question 14

Function of the orbicularis orbis?

Answer 14

Purses lips

Question 15

Function of the buccinator?

Answer 15

Pulls cheeks inwards against teeth, preventing accumulation of food here

Question 16

Name the other oral muscles

Answer 16

Lower group - depressor anguli oris, depressor labii inferioris, mentalis Upper group - risorius, zygomaticus major and minor, levator labii superioris, levator labii superiors alaeque nasi, levator anguli oris

Question 17

If the facial nerve is damaged and the person smiles, which side is affected depending on how the smile appears?

Answer 17

Tissues around mouth and cheeks sag Drawn across to opposite side to that affected while smiling

Question 18

What are the muscles of mastication innervated by?

Answer 18

Mandibular nerve, a branch of the trigeminal nerve

Question 19

Which pharyngeal arch are the muscles of mastication derived from?

Answer 19

1st pharyngeal arch

Question 20

Name the muscles of mastication

Answer 20

Masseter Temporalis Medial pterygoid Lateral pterygoid

Question 21

Which muscles raise the mandible?

Answer 21

Masseter Temporalis Medial pterygoid

Question 22

Action of the temporalis?

Answer 22

Elevates mandible Retracts mandible, pulling jaw posteriorly

Question 23

Action of the lateral pterygoid?

Answer 23

Protracts mandible, pushing jaw forwards Moves jaw from side to side

Question 24

Which nerve supplies the occipitofrontalis muscle?

Answer 24

Facial nerve

Question 25

Where can the facial nerve often be compressed to give Bell’s Palsy?

Answer 25

Near its exit from the cranium at the stylomastoid foramen

Question 26

Which nerve passes through the parotid gland?

Answer 26

Facial nerve

Question 27

How can you tell the difference between a stroke and Bell’s palsy?

Answer 27

Bell’s palsy - all muscles of facial expression are paralysed on one side

Stroke - frontal sparing. Occipitofrontalis and Orbicularis oculi are not paralysed due to their bilateral innervation

Question 28

Which pharyngeal arch are the facial muscles derived from?

Answer 28

Second