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Flashcards in oral functions 3 Deck (60)
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1
Q

define ingestion

A

movement of food from the external environment into the mouth

2
Q

how does ingestion happen

A

accomplished by biting (anterior teeth) and / or using “tools” such as cutlery

3
Q

what role does lips play in ingestion

A
they provide an anterior oral seal
cant control food in the mouth without the muscles around the lips 
- orbicularis oris 
- buccinator
(prevent spillages)
4
Q

what is stage 1 transport

A

moving material from the front of the mouth to the level of the posterior teeth
food is gathered on tongue tip

5
Q

what happens in stage 1 transport

A

the tongue retracts
pulling the material to the posterior teeth
(pull back process)
takes about 1 second

associated with the retraction of the hyoid bone and narrowing of the oropharynx

6
Q

define mechanical processing

A

some solid foods must be broken down and mixed with saliva before they can be swallowed

7
Q

what happens to moist solid food like fruit before transport and swallowing

A

needs to have the fluid removed

8
Q

what teeth chew the food

A

premolar and molars

although molars are not always needed - prosthetic dentistry

9
Q

what happens to some soft foods in mechanical processing

A

they are squashed by tongue against the hard palate

so the tongue is involved in chewing

10
Q

what happens to the hyoid bone in chewing

A

it retracts

11
Q

what does food processing involve

A

the co-ordinated actions of the following muscles
> mandibular muscles (also called the muscles of mastication)
> the supra-hyoid muscles
> tongue muscles
> the lips and cheeks

12
Q

what are the 2 types of tongue muscles

A
  • intrinsic

- extrinsic

13
Q

what is the function of intrinsic tongue muscles

name these

A

alters the shape

  • longitudinal
  • vertical
  • transverse
14
Q

what is the function of extrinsic tongue muscles and name these

A

alters shape and position

  • genioglossus
  • hyoglossus
  • palatoglossus
  • styloglossus
15
Q

what are the tongues actions in chewing

A
  • controls the bolus
  • gathers good and rotates to reposition the bolus on the occlusal table
  • the tongue along with the cheeks, keeps the bolus on the chewing surfaces
  • the tongue and cheeks act in a reciprocal manner to place the food on the occlusal surfaces of the teeth
  • the tongue moves the bolus from side to side of the mouth
  • tongue gathers the bolus for transport
16
Q

what way should patients chew

A

bilaterally

17
Q

what is the problem with chewing unilaterally

A

it is not good for the masticatory system
leads to problems with the masticatory muscles
hypertrophic muscles on one side of the face if chewing unilateral

18
Q

what happens to the tongue during the occlusal and initial opening phases

A

the tongue moves froward

this creates a contact between the tongue and the hard palate

19
Q

what is the squeeze back mechanism

A

> the contact (created during the occlusal and initial opening phases) moves progressively backwards
squeezing the processed food through the fauces
[pushes the bolus so it is ready to be swallowed]
the material accumulates on the pharyngeal surface of the tongue and remains until swallowing occurs

20
Q

when is the mouth continuous with the oropharynx

A

during the processing of solid foods

21
Q

what may be produced during the ingestion of liquids

A

posterior oral seals
liquids are swallowed from the mouth without stage 2 transport

watch video on SDEO

22
Q

what are the phases in the chewing cycle

A
  • opening phase
  • closing phase
  • occlusal phase
23
Q

what happens in the opening phase of the chewing cycle

A

jaw depressor muscles are active

24
Q

what happens in the closing phase of the chewing cycle

A

jaw elevator muscles are active

25
Q

what happens in the occlusal phase of the chewing cycle

A

mandible is stationary / teeth are joined

26
Q

what makes the chew cycle different

A

> different patients according to shape of teeth
different patients according to presence or absence of tooth wear
different foods

27
Q

is the chewing cycle the same as the fossa envelope

A

no

the fossa envelope shows the broader movement of the jaw and mandible

28
Q

what is the chewing cycle shape like when eating brittle food eg carrots

A

narrower / thinner shape

29
Q

what is the chewing cycle shape when eating tough food eg meat

A

broader / wider shape

30
Q

what does the chewing cycle look like in good occlusion

A

consistent shape

lines close together

31
Q

what does the chewing cyclin look like in worn occlusion / bruxism

A

random

wider shape

32
Q

what does the chewing cycle look like in malocclusion

A

no real pattern

33
Q

what are ruminatory mandibular movements

A

when the patient chews there is lots of lateral movements

34
Q

what is the biscuit test

A

patient eats a biscuit so you can examine how they chew

35
Q

if the patient has ruminatory mandibular movements, what needs to be considered when designing the denture

A

the dentures should have teeth with cusps to achieve balanced occlusion (especially when patients have favourable ridge form)
teeth with cusps to ensure the denture is stable when chewing

36
Q

if the patient has vertical (chopping) mandibular movements, what needs to be considered when designing the denture

A

the dentures should have cuspless teeth in this case
(occlusal surface which are evenly worn / flat)
this is the case especially in flat atrophic mandibular ridges

if patient has a worn bite they will struggle to eat differently if they have cusps in their new denture teeth

37
Q

what can the tongue’s movements compromise

A

the retention and stability of the denture
if you dont leave room for the tongue in the denture design then the denture will rock / be mobile when the denture moves

38
Q

why is it important to make sure the denture teeth are on the ridge exactly and do not lean lingually or buccally?

A

this can lead to tongue or cheek biting

use a wax knife to ensure they are straight

39
Q

what do patients need to have to control the denture when incising an apple

A

have neuromuscular control of the denture
patient controls the denture by pushing the tongue to the hard palate to stabilise the denture
raising the tongue = good thing
if this didn’t happen then the denture would wobble when biting the apple

important to watch how patient walks when they enter / checking their medical history to make sure they dont have a neuromuscular disorder or they will have issues wearing a denture

40
Q

what is needed to ensure adequate digestion of most foods

A

minimum chewing with a good dentition is sufficient

41
Q

what does mechanical breakdown of food in the mouth allow

A

facilitates swallowing

might improve digestive efficiency in the GI tract

42
Q

what can deteriorated masticatory performance result in

A

dietary restrictions
avoiding foods that are difficult such as green veg and some meats

there is no clear evidence that poor mastication causes malnutrition in people with GI tract disorders especially with modern foods and methods of preparation
so if a person is able to eat in a reasonable way they should be okay healthwise

43
Q

what is the shortened dental arch (SDA)

A

20 teeth is considered the minimum for acceptable
> masticatory function
> aesthetics (premolar to premolar)
> maintenance of oral hygiene

need to have 20 health units (either natural teeth or implants or sound restored teeth)

44
Q

what is the concept behind the shortened dental arch

A
  • absent molar teeth are only replaced if their absence gives rise to problems
  • SDA provides sufficient occlusal stability
  • SDA provides satisfactory comfort and appearance
  • chewing and comfort were not significantly enhanced by the provision of RPDs
45
Q

what must attention be given to for a shortened dental arch to exist

A

maintaining the health of the remaining teeth

patient must be a good, regular attender who keeps good control of their oral hygiene

46
Q

what age group does a functional SDA not work well for

A

elderly

the number of people who might have a functional SDA fails dramatically with age

47
Q

what are reduced in complete denture wearers

A

biting forces are reduced
complete dentures = mucosa borne support (mucosa of residual ridge)
this is not designed to bear masticatory loads or to tolerate forces

48
Q

what do patients lack in complete dentures

A

lack proprioception

no PDL in complete dentures

49
Q

how can bite forces be increased in dentures

A

supporting the dentures on teeth or implants

not everyone can tolerate the surgery of implants or meet the cost

50
Q

what are the 3 types of prosthesis that can be used to replace missing teeth

A
  • mucosa supported prosthesis
  • tooth supported prosthesis
  • bone supported prosthesis
51
Q

what can be given to a patient in mucosa supported prosthesis

A
  • complete denture

- RPD

52
Q

what can be give to a patient in tooth supported prosthesis

A
  • RPDs

- fixed (‘bridges’)

53
Q

what can be given to a patient in bone supported prosthesis

A
  • implants
54
Q

what are problems associated with acrylic partial dentures

A

> not used long term
not well supported and causes resorption of bone where forces are applied
use gingivally approaching claps that may cause gingival recession on the gingival margin

55
Q

what is included in a fixed-fixed bridge

A

all ceramic

  • abutment teeth
  • retainer
  • pontic
56
Q

what is a cantilever bridge

A

used in tooth supported prosthesis
a pontic connected to a retainer at one end only
used to replace single teeth
only one retainer is used to support the bridge
not recommended when occlusal forces on the pontic will be heavy

57
Q

what is an adhesive bridge / resin bonded bridge

A

an immediate temporary adhesive bridge is appropriate followed by a permanent bridge once the tissues have settled
quick
non-destructive / conservative of tooth tissues
aesthetic
durable (good life span)
has wings on the palatal aspects of abutment teeth
nothing on labial / buccal surfaces

58
Q

how is the occlusal load transmitted to the bone in mucosa borne support

A

via the oral mucosa

not recommended

59
Q

how is the occlusal load transmitted to the bone in tooth borne support

A

via rests and PDL

recommended

60
Q

what are implants

A

bone supported prosthesis
screws / fixtures that will bare the forces
fixed so dont need to be removed for cleaning