module 3

Question 1

masseter

Answer 1

Origin: Inferior aspect of the zygomatic arch as well as the inferior aspect of the body and maxillary process of the zygoma
Insertion: Lateral surface of the ramus of the mandible
Action: Elevation of the mandible

Question 2

temporalis

Answer 2

Origin: temporal fossa
Insertion: coronoid process of mandible
Action: elevation of mandible

Question 3

medial pterygoid

Answer 3

Origin: Superficial head - Infratemporal surface of maxilla

Deep head - medial surface of lateral pterygoid plate

Insertion: Medial surface of the ramus of the mandible, near the angle

Action: Elevation, protrusion of the mandible when working bilaterally. Contralateral movement of the mandible when working unilaterally.

Question 4

lateral pterygoid

Answer 4

Origin:
Upper head - inferior aspect of the greater wing of the sphenoid bone
Lower head - lateral surface of the lateral pterygoid plate
Insertion: Capsule of the TMJ and condyloid process of mandible.
Action: Protrusion of the mandible when working bilaterally. Contralateral movement of the mandible when working unilaterally.

Question 5

stylohyoid

Answer 5

origin: styloid process
insertion: lateral area of hyoi
action: elevates hyoid bone
nerve supply: facial nerve CN7

Question 6

mylohyoid

Answer 6

origin: mylohyoid line
insertion: body of hyoid bone
action: depresses mandible, elevates hyoid bone
nerve supply: mandibular nerve- CNV3

Question 7

digastric

Answer 7

origin (anterior belly): inferior surface of mental protuberance
posterior belly: medial to mastoid process
insertion: intermediate tendon sling
action: depresses mandible, elevates hyoid bone
nerve supply: anterior belly: mandibular nerve
posterior belly- facial nerve

Question 8

geniohyoid

Answer 8

origin: deep surface of mandibular body
insertion: medial aspect of hyoid bone
action: depresses mandible, elevates hyoid bone
nerve supply: C1

Question 9

Sternohyoid

Answer 9

Origin: manubrium
Insertion: body of hyoid bone
Action: depress hyoid bone
Nerve supply: ansa cervicalis (C1-3)

Question 10

sternothyroid

Answer 10

Origin: manubrium
Insertion: thyroid cartilage
Action:depresses larynx
Nerve supply: ansa cervicalis (C1-3)

Question 11

thyrohyoid

Answer 11

Origin: thyroid cartilage
Insertion: body and greater horn of hyoid bone
Action: de]ress hyoid bone, elevates larynx
Nerve supply: c1

Question 12

Orbicularis oculi

Answer 12

Palpebral Part:
Origin: Medial palpebral ligament
Insertion: Lateral palpebral raphe
Action: Gently closes the eye

Orbital Part: Forms an uninterrupted sphincter around the eye
Origin & Insertion: Nasal part of frontal bone, frontal process of maxilla, medial palpebral ligament
Action: Forcefully closes the eye. Shuts your eyes tightly.

Question 13

Orbicularis oris

Answer 13

The orbicularis oris muscle forms a ring around the mouth. It is a complex muscle with lots of attachments.
Origin & Insertion: Maxilla and mandible in the midline, other surrounding muscles laterally
Action: To close the mouth or purse the lips, such as when whistling or kissing.

Question 14

Occipitofrontalis

Answer 14

Origin:
Frontal belly - skin and muscles superior to eyebrows
Occipital belly - lateral part of superior nuchal line (occiput)
Insertion: Both parts insert into the galea aponeurosis
Action:
Frontal belly - Raises eyebrows which wrinkles the forehead
Occipital belly - draws scalp posteriorly

Question 15

Buccinator

Answer 15

This is the primary muscle of the cheek. It has an interesting relationship with one of the salivary glands called the parotid gland. The duct of the parotid gland pierces the buccinator muscle on the way to its opening in the oral cavity.

Origin: Posterolateral parts of the external surface of both the maxilla and mandible

Insertion: Orbicularis oris muscle and the lateral aspect of the lips

Action: Compresses cheek medially. This primarily helps to keep food between the teeth when chewing.