Toothwear and Occlusion Flashcards

1
Q

what is occlusion?

A

the study of the relationships between the upper and lower teeth when they are closed together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the functional purpose of bringing the teeth together?

A

for chewing and swallowing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the parts of the masticatory system?

A

teeth, periodontal tissues, jaws, temporo-mandibular joints, muscles of mastication, nervous control

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what must occur for occlusion to occur?

A

the muscles of mastication have to move the jaws into position to allow the teeth to contact

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

where are forces transmitted during chewing?

A

down the long axes of the teeth into the robust base of the skull

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what does the pulp do during chewing?

A

sends signals to the brain which sends signals to the muscles of mastication to regulate the movement of the jaws (sensitive feedback)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what does sensitive feedback do?

A

regulate the amount of force applied to the teeth which is important in tooth preservation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what does the resting position rely on?

A

neuromuscular memory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what is intercuspal position?

A

the position in which the teeth are maximally meshed together and the position the mandible aims for at the end of chewing

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the occlusion pattern on posterior teeth?

A

the lower buccal cusps and upper palatal cusps occlude against the fossae and marginal ridges of the opposing teeth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the occlusion pattern on anterior teeth?

A

the lower incisal egses and canine tips occlude against the cingulum area of the opposing teeth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what happens if forces are not directed down the long axes of the teeth?

A

there can be teeth tilting and pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is balanced occlusion?

A

even, bilateral contacts in ICP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what does balanced occlusion provide?

A

stability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what does the mandibular condyle do during protrusion?

A

moves downwards and forwards in the mandibular fossa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the steps of chewing?

A

1 - jaw opens , 2 - moves left or right , 3 - jaw comes back up

17
Q

when does group function occur?

A

when the mandible swings laterally and there are several teeth contacting

18
Q

who is group function most commonly seen in?

A

patients with toothwear or unstable occlusions

19
Q

what is canine guidance?

A

when the mandible moves laterally with the tips of the canines being the only teeth in the arch which are touching

20
Q

what is an articulator?

A

a device in which dental casts are held in relationship to each other and which can replicate to varying extents mandibular movement

21
Q

what do you do when examining occlusion?

A

look at tooth position in each arch - are there irregularities that might impact on the occlusion? look at the teeth in ICP - does it look stable, are there unopposed, drifted or over-erupted teeth? locate the contact points in ICP - where are they, how many are there? which teeth provide guidance in protrusion and lateral excursions?

22
Q

what are the 3 types of toothwear?

A

attrition, erosion, abrasion

23
Q

what is attrition?

A

the loss of tooth substance caused by contact between occluding surfaces

24
Q

what is attrition caused by?

A

parafunctional rather than functional activity

25
what does parafunction mean?
purposeless clenching or grinding of the teeth (bruxism)
26
what are facets?
little bits of the teeth that are worn away that coincides with the opposing tooth
27
what is erosion?
the loss of tooth substance by a chemical process (acid) not involving bacterial action
28
what can be seen in tooth erosion?
dentine
29
what are the causes of tooth erosion?
diet, regurgitation, environmental
30
what is the effect of tooth erosion on amalgam restorations?
they appear to be raised above the clinical height of the crown as they are not affected by the acid
31
what is abrasion?
loss of tooth substance caused by abnormal rubbing from a non-dental object
32
what causes abrasion?
most commonly a toothbrush with overbrushing/trauma
33
in abrasion, how does the dentine surface get brushed away?
because the gum has receded
34
why may restorations fail?
secondary caries, fracture of the restoration or tooth pulp death, incompatibility with periodontal tissues, poor appearance
35
what is gingivitis associated with?
poorly fitting crown margins
36
what should an intra-oral exam include?
assessment of the occlusion - both static and functional, looking for signs of toothwear, evaluation of existing restorations