Muscles of Mastication and Muscles of Facial Expression

Question 1

What are the muscles of mastication?

Answer 1

Masseter
Temporalis
Lateral pterygoid
Medial pterygoid

Question 2

What is the origin of the temporalis muscle?

Answer 2

Floor of temporal fossa and deep surface of temporal fascia

Question 3

What is the insertion of the temporalis muscle?

Answer 3

Tip and medial surface of coronoid process
Anterior border of ramus of mandible

Question 4

What is the innervation of the temporalis muscle?

Answer 4

Mandibular nerve

Question 5

What is the action of the temporalis muscle?

Answer 5

Elevates mandible, closing jaw
Posterior fibres retrude mandible after protrusion

Question 6

What is the origin of the masseter muscle?

Answer 6

Inferior border and medial surface of the zygomatic arch

Question 7

What is the insertion of the masseter muscle?

Answer 7

Lateral surface of ramus of mandible
Coronoid process

Question 8

What is the innervation of the masseter muscle?

Answer 8

Mandibular nerve

Question 9

What is the action of the masseter muscle?

Answer 9

Elevates the mandible, closing jaw
Deep fibres retrude the mandible

Question 10

What is the origin of the medial pterygoid muscle?

Answer 10

Deep head: Medial surface of the lateral pterygoid plate and pyramidal process of palatine bone
Superficial head: Tuberosity of maxillay

Question 11

What is the insertion of the medial pterygoid muscle?

Answer 11

Medial surface of ramus of mandible, inferior to mandibular foramen

Question 12

What is the innervation of the medial pterygoid muscle?

Answer 12

Mandibular nerve

Question 13

What is the action of the medial pterygoid muscle?

Answer 13

Elevates the mandible, closing the jaw
Acting together, it protrudes the mandible
Acting alternately, its produces a grinding motion

Question 14

What is the origin of the lateral pterygoid muscle?

Answer 14

Superficial head: Greater wing of sphenoid bone
Inferior head: lateral surface of lateral pterygoid plate

Question 15

What is the innervation of the lateral pterygoid muscle?

Answer 15

Neck of mandible
Articular disc
Capsule of TMJ

Question 16

What is the innervation of the lateral pterygoid muscle?

Answer 16

Mandibular nerve

Question 17

What is the action of the lateral pterygoid muscle?

Answer 17

Acting together, it protrudes the mandible
Depresses chin
Acting alternately and alone, it produces side-to-side movements of the mandible

Question 18

Which are the muscles of facial expression around the eye?

Answer 18

Oribicularis oculi
Frontalis
Corrugator supercilli

Question 19

Which muscles of facial expression are found around the nose?

Answer 19

Procerus
Nasalis
Depressor septi

Question 20

Which muscles of facial expression are found around the mouth?

Answer 20

Orbicularis oris
Buccinator
Upper group
Lower group

Question 21

Which muscles make up the upper group of muscles of facial expression around the mouth?

Answer 21

Risorius
Zygomaticus major
Zygomaticus minor
Levator anguli oris
Levator labii superioris
Levator labii superioris alaeque nasi

Question 22

Which muscles make up the lower group of muscles of facial expression around the mouth?

Answer 22

Mentalis
Depressor labii inferioris
Depressor anguli oris

Question 23

What is the modiolus?

Answer 23

The intersection of the muscles of facial expression in the corner of the mouth?

Question 24

Which nerve innervates the muscles of facial expression?

Answer 24

Facial nerve

Question 25

What is the origin of the orbicularis oris?

Answer 25

Midline of maxilla superiorly and mandible inferiorly

Question 26

What is the insertion of orbicularis oris?

Answer 26

Skin of mucous membrane of lips and onto itself

Question 27

What is the action of orbicularis oris?

Answer 27

Narrows mouth and closes lips

Question 28

What is the origin of the buccinator?

Answer 28

Posterior part of maxilla Mandible opposite molar teeth Pterygomandibular raphe

Question 29

What is the insertion of the buccinator?

Answer 29

Into the lips Blends with the orbicularis oris

Question 30

What is the action of the buccinator?

Answer 30

Contraction presses the cheek against the teeth Helps keep food out of the vestibule of the mouth and between the teeth Muscle is relaxed when cheeks are puffed out

Question 31

What facial expression is produced by the risorius?

Answer 31

Grinning, through contraction by pulling the corner of the mouth upwards and laterally

Question 32

What is the origin and insertion of the levator labii superioris?

Answer 32

Origin: Arises from the maxilla superior to the infraorbital foramen Insertion: Skin of upper lip

Question 33

What facial expression is produced by the levator labii superioris?

Answer 33

Sadness

Question 34

What facial expression is produces by the zygomaticus major and minor?

Answer 34

Smiling by raising the corner of the mouth and moving it laterally

Question 35

What is the origin and insertion of the zygomaticus major?

Answer 35

Origin: Arises deep to orbicularis oris Insertion: Skin at corner of mouth

Question 36

What is the origin and insertion of the zygomaticus minor?

Answer 36

Origin: Arises from zygomatic bone Insertion: Upper lips medial to corner of mouth