muscles of mastication

Question 1

what are the 4 types

Answer 1

• masseter
• temporalis
• media pterygoid
• lateral pterygoid

Question 2

origin of masseter

Answer 2

lower border and inner surface of the zygomatic arch to the lateral surface of the ramus

Question 3

what is the muscle divided into

Answer 3

• superficial
• intermediate
• deep layers

Question 4

insertion (masseter)

Answer 4

outer surface of the ramus of the mandible near angle of mandible

Question 5

action

Answer 5

strong elevator of the mandible, it locks the jaw (screw hoe movement)

Question 6

what is lock jaw?

Answer 6

spasms of the masseter during tetanus

Question 7

whats a trismus?

Answer 7

involvement of masseter in facial space infections

When your jaw muscles become so tight that you can’t open your mouth

Question 8

what is the massetric space called?

Answer 8

space between mandible and the muscle

Question 9

describe what the temporalis looks like

Answer 9

fan shaped muscle that occupies the temporal fossa

Question 10

origin (temporalis)

Answer 10

temporal fossa

Question 11

insertion

Answer 11

apex, anterior border, inner surface of coronoid process of mandible (behind zygomatic arch)

Question 12

action

Answer 12

elevation and retraction of the mandible

Question 13

what is gillies

Answer 13

fraction to the zygomatic arch - cant move the mandible up

Question 14

origin of lateral pterygoid

Answer 14

superior head - infratemporal surface and infratemporal crest of the greater wing of the sphenoid bone

inferior head - lateral surface od the lateral pterygoid plate

Question 15

insertion of lateral pterygoid

Answer 15

neck of the mandible
articular disc of tmj
anterior aspect of te capsule of tmj

Question 16

actions lateral pterygoid

Answer 16

• depression of mandible
  protusion of mandible
  lateral exursive movements along with the med pterygoid

Question 17

applied anatomy

Answer 17

involved in temporomandibular disorderes

significant displacement of coronal fractures

Question 18

original of medial pterygoid

Answer 18

superior head from max tuberosity and neighbouring part of the palatine bone

Question 19

insertion

Answer 19

rough area on the medial surface of the ramus and angle of mandible

Question 20

actions

Answer 20

• elevation
• protrusion
• lateral excurisve movements along with th elateral pterygoids

Question 21

applied anatomy

Answer 21

can cause significant displacemnt of mandibular and angle fractures

Question 22

LOOK AT PHOTOS

Answer 22

you got this

Question 23

what are the fucntional movements of the mandibe

Answer 23

• depression: initial stage, bilateral lateral pterygoid
• elevation: bilateral masseteres, temporalis and medial pterygoid
  -protrusion: bilateral med and lat pterygoids
  -retrusion: bilateral middle and posterior fibres of temporalis
  -lateral: contralateral med and lat pterygoids and post fibres of ipsilateral temporalis

Question 24

Features of the temporomandibular joint TMJ

Answer 24

look at ppt

seperated into upper and lower joint cavities by a fibrocartilagenous disc

Question 25

3 main ligments

Answer 25

capsule lateral tmj ligament sphenomaandibular ligament

Question 26

describe the articular disc

Answer 26

- oval shaped, avascular, fibro - cartilagenous structure - attched peripherally to the capsule (ligament) - upper surface is concavo-convex -lower surface is concave

Question 27

recap of movements

Answer 27

elevation depression retraction protraction side to side movements