Oral Biology

Question 1

name the four muscles of mastication

Answer 1

masseter
temporalis
lateral pterygoid
medial pterygoid

Question 2

name the origin, insertion and action of the masseter

Answer 2

origin - zygomatic arch
insertion - angle of mandible
action - elevation

Question 2

name the origin, insertion and action of the lateral pterygoid

Answer 2

origin - lateral surface of lateral pterygoid head
insertion - condyle and intra-articular disc
function - protrudes and lateral deviates the mandible, also depresses!

Question 2

name the origin, insertion and action of the temporalis

Answer 2

origin - floor of temporal fossa
insertion - coronoid process and anterior border of ramus
action - elevates and retracts

Question 3

what muscle is most likely to be related to clicking of the TMJ

Answer 3

lateral pterygoid

Question 4

how is the lateral pterygoid best tested

Answer 4

by testing the ability of the mandible to depress (mouth to open)

Question 5

name the origin, insertion and action of the medial pterygoid

Answer 5

origin - lateral pterygoid plate and maxillary tuberosity
insertion - medial surface of mandible
action - elevates and protrudes mandible

Question 6

what may accidentally cause trismus when giving a patient an IDB

Answer 6

hitting the medial pterygoid

Question 7

what is the first movement of the mandible called upon opening

Answer 7

rotation - the condyle rotates on a hinge axis for the first 20mm of opening

Question 8

what is the second movement in mandibular opening called when opening the mouth

Answer 8

translation - the wider opening of protrusive or retrusive movements (sliding)

Question 9

what occurs in mandibular protrusion

Answer 9

both condyles leave the glenoid fossae and move forward along the articular eminences

Question 10

what shape does the rotation and translation movements of the mandible form

Answer 10

envelope

Question 11

what are the two types of muscle fibres

Answer 11

type I - slow low forces
type II - fast stronger forces

Question 12

name the four suprahyoid muscles

Answer 12

digastric
mylohyoid
geniohyoid
stylohyoid

Question 12

name the four infrahyoid muscles

Answer 12

sternohyoid
omohyoid
thyrohyoid
sternothyroid

Question 13

what are the three intrinsic tongue muscles and their function

Answer 13

longitudinal, vertical and transverse
they alter shape of the tongue

Question 14

what are the four extrinsic muscles of the tongue

Answer 14

genioglossus
hyoglossus
palatoglossus
styloglossus
they alter shape and position

Question 15

what two facial muscles are associated with chewing and controlling the bolus in the mouth

Answer 15

buccinator
orbicularis oris

Question 16

what sensory nerves are involved in innervating lower molars

Answer 16

trigeminal nerve - mandibular division - IAN

Question 17

what might occur if the IAN is hit while administering an IDB

Answer 17

patient will feel an electric shock to half the lip

Question 18

what are the five cranial nerves involved in the gag reflex

Answer 18

trigeminal
glossopharyngeal
vagus
accessory
hypoglossal

Question 19

name four signs/ symptoms of Bell’s Palsy

Answer 19

inability to wrinkle brow
drooping eyelid
inability to puff cheeks
drooping mouth and food stuck in cheek

Question 20

what are the five branches of the facial nerve

Answer 20

temporal
zygomatic
buccal
mandibular
cervical

Question 21

what is Bell’s Palsy

Answer 21

any type of facial paralysis that does NOT have associated causes

Question 22

what should patients be instructed to do when they have any type of facial paralysis

Answer 22

reassure them eye protected with a loose pad until corneal blink reflex returns

Question 23

what is the biggest advantage of keeping teeth/ roots for over dentures

Answer 23

periodontal mechanoreceptors - allow finer discrimination of food textures, tooth contacts and levels of functional loading

Question 24

what is dysphagia

Answer 24

inability to swallow

Question 25

name four causes of dysphagia

Answer 25

stroke MS GORD tumours

Question 26

what nerve supplies motor function to the tongue

Answer 26

hypoglossal nerve

Question 27

what sensory nerve is the anterior 2/3rds of the tongue innervated by

Answer 27

lingual nerve (and chorda tympani)

Question 28

what is the sensory innervation to the posterior 1/3rd of the tongue

Answer 28

glossopharyngeal nerve

Question 29

what are the 3 stages in the feeding sequence

Answer 29

ingestion stage I transport - chewing mechanical processing

Question 30

what is involved in ingestion stage of feeding

Answer 30

food moved from external environment to mouth lips provide anterior oral seal facial muscles control the food bolus

Question 31

what is involved in stage I transport during feeding process

Answer 31

material moves from front of mouth to level of posterior teeth food gathers on tongue tip and tongue retracts - pulling food to back of mouth

Question 32

what is involved in the mechanical processing phase of the feeding sequence

Answer 32

solid foods mixed with saliva some foods squashed by tongue against hard palate

Question 33

what muscles are involved in food processing

Answer 33

mandibular muscles supra-hyoid muscles tongue muscles lips and cheeks

Question 34

name five actions of the tongue in chewing

Answer 34

controls the bolus gathers food and rotates to reposition the bolus on occlusal table keeps bolus on chewing surfaces moves bolus from side to side in the mouth collects bolus for transport at final stage

Question 35

what is the squeeze back mechanism of food chewing

Answer 35

forward movement of the tongue during occlusal and initial opening phases creates contact between tongue and hard palate the contact zone progressively moves posteriorly this squeezes the bolus through the fauces

Question 36

how are liquids ingested

Answer 36

liquids are swallowed from the mouth - without any stage II transport

Question 37

where are solids swallowed from

Answer 37

oro-pharynx

Question 38

what occurs to the chewing cycle in brittle compared to tough food

Answer 38

brittle (eg carrot) = narrow tough (eg meat) = wider

Question 39

what is suggested if a patient attends the dental practice with a denture that is evenly worn flat

Answer 39

vertical chopping movements

Question 40

what denture teeth might be more suitable for people who have vertical mandibular movements

Answer 40

cuspless

Question 41

what is a shortened dental arch

Answer 41

20 teeth (or functional units if a bridge is included) is the minimum number of units for acceptable masticatory performance, aesthetics and maintenance of oral hygiene

Question 42

what occurs with respect to biting forces in complete denture wearers

Answer 42

biting forces are reduced biting load is carried by mucosa of residual ridge - causes resorption with excessive forces

Question 43

when is a cantilever bridge contraindicated

Answer 43

where there is heavy occlusal forces on the pontic

Question 44

what are the three phases of swallowing

Answer 44

buccal phase (voluntary) pharyngeal stage (involuntary) oesophageal phase (involuntary)

Question 45

what is the difference between swallowing food and swallowing liquid

Answer 45

liquid is swallowed from the mouth proper (oral seal) food is swallowed from oro-pharynx (no oral seal)

Question 46

what separates the mouth from the pharynx

Answer 46

posterior oral seal

Question 47

what prevents reflux from stomach to oesophagus and from oesophagus to pharynx

Answer 47

stomach to oesophagus - lower oesophageal sphincter oesophagus to pharynx - upper oesophageal sphincter

Question 48

what is attrition

Answer 48

tooth wear caused by contact between occluding teeth (bruxists)

Question 49

what is abrasion

Answer 49

most commonly tooth wear due to using too much abrasive force with a toothbrush mainly seen on cervical area

Question 50

what is dysphasia (WITH AN S)

Answer 50

language disorder which involves Broca's and Wenicke's area in the brain

Question 51

what is dysphagia (WITH A G)

Answer 51

difficulty/ inability swallowing

Question 52

what is odynophagia

Answer 52

person experiences extreme pain when swallowing

Question 53

what is dysarthria

Answer 53

difficulty speaking caused by problems with the muscles used in speech

Question 54

name five oral causes of speech and language defects

Answer 54

malocclusion CLP tongue related dry mouth loss of teeth - denture related

Question 55

name three things that might affect the tongues function

Answer 55

tongue tie partial atrophy of the tongue tongue stud piercing

Question 56

what are mandibular tori

Answer 56

benign neoplasms - bony overgrowths only becomes a problem if patient requires lower partial denture

Question 57

name two issues with denture design that can affect speech

Answer 57

denture base plate is too thick artificial teeth not set properly

Question 58

what problem with speech may a denture base that is too thick cause

Answer 58

patient inability to say 's' sound and it all turns to 'sh' sounds

Question 59

what problem with speech may occur when denture teeth are set in the wrong occlusal planes

Answer 59

problems making 'f', 'v' and 'ph' sounds

Question 60

what is embouchure

Answer 60

position and use of lips, tongue and teeth when playing a wind instrument