Week 10

Question 1

mandible formation

Answer 1

formed by two bones fused at the mental symphysis (= chin joint)

Question 2

mandibular body

Answer 2

horseshoe-shaped lower part of the mandible, holding the lower teeth

Question 3

ramus

Answer 3

the vertical part of connecting the skull

Question 4

angle of the mandible

Answer 4

where the body and ramus of the mandible meet

Question 5

condyle and coronoid processes

Answer 5

two protrusions at the top of the ramus
- condyle is the posterior process
- coronoid is the anterior process

Question 6

mandibular notch

Answer 6

the depression between the condyle and the coronoid process

Question 7

mental/mandibular symphysis

Answer 7

external surface of the mandible marked in the median line by a faint ridge, where two lateral halves of the mandible fused at an early period in life

Question 8

mental protruberance

Answer 8

triangular projection on the anterior part of the mandible located at the midline

Question 9

mental spines

Answer 9

small ridges on the inner surface of the mandible; serve for attachment for the genioglossus and geniohyoid muscles

Question 10

superior mental spines serves the origin for the ___ muscle

Answer 10

genioglossus

Question 11

inferior mental spines serves the origin for the ___ muscle

Answer 11

geniohyoid

Question 12

mylohyoid line

Answer 12

body ridge that is the attachment point for the mylohyoid muscle

Question 13

temporomandibular joint (TMJ)

Answer 13

connects the mandible to the temporal bone of the skull

Question 14

two types of foramen in the jaw

Answer 14

mandibular foramen
mental foramen

Question 15

mandibular foramen

Answer 15

entry point for the inferior alveolar nerve and vessels located in the internal surface of the ramus

Question 16

mental foramen

Answer 16

small opening that allows the passage of the mental nerve and blood vessels, located on the external surface of the mandible, near the apex of the mandibular premolar teeth

Question 17

jaw muscles are categorised into ___ and ___

Answer 17

elevators (lifters) ; depressors (lowerers)

Question 18

masseter muscle (origin, insertion, function)

Answer 18

origin: zygomatic arch
insertion: inserts into the ramus and angle of the mandible
function: elevates the mandible to close the jaw
- divided into the deep and shallow head

Question 19

temporal fossa

Answer 19

a shallow depression on the lateral side of the skull that serves as the origin of the temporalis muscle

Question 20

bony boundaries of the temporal fossa

Answer 20

inferior lateral part of the frontal bone, inferior part of the parietal bone, squamous part of the temporal bone, sphenoid bone

Question 21

temporalis muscle (origin, insertion, function)

Answer 21

origin: temporal fossa
insertion: coronoid process of the mandible
function: elevates and retracts the mandible
- has a fan-like shape that allows for a wide range of jaw movements

Question 22

medial pterygoid muscle (origin, insertion, function)

Answer 22

origin: sphenoid palatine and maxilla bones
insertion: inner surface of the mandible
function: elevates the mandible to the masseter

Question 23

lateral pterygoid muscle (origin, insertion, function)

Answer 23

origin: sphenoid and maxilla
insertion: TMJ disk and condyle of the mandible
function: controls side-to-side movement of the jaw, and aids in protruding the jaw

Question 24

jaw depressor muscles

Answer 24

responsible for lowering the mandible and stabilise the hyoid bone and assist in tongue movements
- consists of the anterior belly of the digastric muscle, mylohyoid, and geniohyoid

Question 25

four major extrinsic tongue muscles

Answer 25

genioglossus, palatoglossus, hyoglossus, styloglossus

Question 26

genioglossus (gg) (origin, insertion, function)

Answer 26

origin: mental spine of the mandible insertion: inserts throughout the tongue, from tip to root function: protracts, depresses, and grooves the tongue

Question 27

3 sub-divisions of the genioglossus

Answer 27

anterior (GGa) = lowers and retracts the tongue root middle (GGm) = lowers and pulls forward the tongue body and creates grooves posterior (GGp) = pulls tongue root forward

Question 28

palatoglossus (PG) (origin, insertion, function)

Answer 28

origin: palatine aponeurosis insertion: sides of the tongue body function: elevates the tongue, assists in uvular constrictions, and narrows the OPI

Question 29

hyoglossus (HG) (origin, insertion, function)

Answer 29

origin: greater horn of the hyoid bone insertion: sides of the tongue function: pulls the tongue down and back, especially the back of the tongue

Question 30

styloglossus (SG) (origin, insertion, function)

Answer 30

origin: styloid process of the temporal bone insertion: sides of the tongue, interlocking with intrinsic tongue muscles function: traditionally thought to raise and retract the tongue; its rule in speech is under review though

Question 31

what is an ultrasound

Answer 31

a device that uses high-frequency sound waves for medical diagnostic imaging

Question 32

generation of sound waves

Answer 32

piezoelectric crystals = materials that can convert mechanical energy into electrical energy and vice versa --> frequencies range from 2 to ~ 18 MHz

Question 33

___ tissues and fluid-filled organs allow most sound waves to pass through, while ___ structures like bones reflect more sound waves back to the transducer

Answer 33

soft ; hard

Question 34

how do sound waves travel through the body and interact with different tissues?

Answer 34

- sound waves travel through the body, interacting with various tissues - different structures reflect sound waves back to the transducer to various degrees at boundaries between mediums, much of the transmitted wave bounces back (reflection) - reflection occurs because the wave cannot easily transfer energy across the impedance boundary

Question 35

what does the time between echoes in an ultrasound tell us?

Answer 35

the time it takes the echoes to return to the transducer and the strength (amplitude) of these tells us the distance and characteristics of the tissue encounters

Question 36

how does the ultrasound create images

Answer 36

ultrasound processes the echoes derived by the transducer to generate images based on distance and strength of the waves, the machine will construct a real-time image/video of the internal structures

Question 37

how can the ultrasound be used for speech?

Answer 37

to track the tongue surface, shape, fronting, retracting, etc. when an individual is speaking. it can also measure velum movement but there are very few studies with this

Question 38

contour analysis

Answer 38

a summary of trends in the tongue contours/shapes