Muscles Of The Head

Question 0

What are the 5 muscles of mastication(chewing)?

Answer 0

1. ) Temporalis
2. ) Masseter
3. ) Medial pterygoid (“terygoid”)
4. ) Lateral pterygoid
5. ) Digastricus

Question 1

Temporomandibular joint (TMJ)
What are its 5 movements?

Answer 1

Two bones coming together and allowing movement.

1. )Elevation(closing)
2. )Depression(opening)
3. )Protrusion (bringing jaw forward)
4. )Retraction (bringing jaw back)
5. ) rotation or lateral movement( side to side movement)

Question 2

What are the structures of the 5 mastication muscles?

Answer 2

1. ) Temporalis:
   - attaches to temporal bone
   - runs deep to the zygomatic arch
2. ) Masseter:
   - attaches to zygomea and mandible
   - one of the strongest muscles in the body
3. ) Medial pterygoid:
   - deep to mandible
4. ) Lateral pterygoid:
   - look like a wing
5. ) Digastricus:
   - two bellys anterior/posterior

Question 3

What are 5 functions of the mastication muscles?

Answer 3

1. ) Temporalis:
   - powerful in elevation of mouth( closes mouth)
2. ) Masseter:
   - powerful elevation
3. ) Medial terygoid:
   - works with the Masseter to form a swing to support the jaw.
4. ) Lateral terygoid:
   - protrusion
   - same side lateral movement
   - stability with joints
5. ) Digastricus:
   - Anterior- depression/elevates the hyoid
   - posterior- evelates hyoid/activate during swallowing.

Question 4

What are the 4 muscles of facial expression and there function?

Answer 4

1. ) Occipitofrontalis: muscle above eyebrows
2. ) Zygomaticus major and minor: pulls the mouth upward: as in smiling
3. ) Depressor anguli oris: pulls moth downward as in frowning
4. ) Platysma: depresses the mandible and tightens the skin over the anterior neck

Question 5

Sternocleidomastoid (SCM) function and structure

Answer 5

Structure:

• Attaches to sturnum, mastoid process and clavicle
• attaches to head
• superficial to caroid artery, vages nerve and jugular vein
• most superficial

Function:

• flexion
• lateral flexion
• rotation to side