Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Orthodontics > Aetiology of Malocclusion > Flashcards

Aetiology of Malocclusion Flashcards

1
Q

What is the definition of a local cause of malocclusion?

A

A localised problem or abnormality within either arch, usually confined to one, two or several teeth proceeding a malocclusion.

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

What is a supernumerary tooth/teeth?

A

A tooth or tooth like entity which is assertional to the normal series.

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

What are the four types of supernumerary?

A

Conical
Tuberculate
Supplemental
Odontome

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

What is a conical supernumerary?

A

Conical shaped extra tooth
Usually doesn’t impact eruption of the permanent tooth but can displace the adjacent tooth.
Usually close to the midline.

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

What is a tuberculate supernumerary tooth?

A

Tend not to erupt, barrel-shaped tooth.
Usually come in pairs.
Can cause permanent teeth to not erupt.

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

What is a supplemental supernumerary tooth?

A

Extra tooth of normal morphology.
Commonly upper laters or lower incisors.
Can be third molars, fourth molars.

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

What is hypodontia?

A

Developmental absence of one or more teeth.
Strong genetic component.

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

What are the most common teeth to be missing in a child?

A

Upper laterals and second premolars.

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

In terms of retention of primary teeth, what would set alarms bells off?

A

A difference of more than 6 months between shedding of contralateral teeth.

Investigate with radiograph (OPT).

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

Why might a primary tooth be retained in the mouth?

A

Lack of permanent successor
Ectopic successor
Infra-occluded primary molars
Dentally delayed in terms of development
Pathology/supernumerary

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

What are the treatment options for a patient with a retained primary tooth and no permanent successor?

A

Maintain primary tooth if good prognosis
Extract deciduous tooth early and encourage spontaneous space closure.

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

What does it mean if a tooth is infra-occluded?

A

Process where a tooth fails to achieve pt maintain it’s occluded relationship with adjacent teeth.

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

What signs would suggest a tooth is infra-occluded?

A

Ankylosis- lack of lamina dura on radiograph.
Tooth is below the occlusal surface with adjacent teeth.
Percussion sound.

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

What is the classification of infraoccluded teeth?

A

Slight- between occlusal surface and interpoximal contact, less than 2mm.

Moderate- Within occlusion-gingival margins of inter proximal contact.

Severe- Below inter proximal contact point.

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

Why might a patient prematurely loose a primary tooth?

A

Trauma
Caries
Periodical pathology
Resorption by successor

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

What is a balancing extraction?

A

By extraction of a tooth from the opposite side of the same arch.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is a compensating extraction?

A

By extraction of a tooth from the opposing arch of the same side.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Why might you need to do a balancing or compensating extraction?

A

To maintain occlusal relationships.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Do you require a compensating or balancing extraction if you prematurely lose an incisor tooth?

A

No, not required.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Do you require a compensating or balancing extraction if you prematurely lose a canine?

A

Balancing extraction required because it can cause a centre line shift, maybe some medial drift of buccal segments.

21
Q

What are the consequences of losing a primary molar tooth early?

A

Mesial drift of 6’s.
More space loss with e’s than d’s
More space loss in upper than lower.

22
Q

When should 6’s be assessed for prognosis?

A

8-9 dental age

23
Q

What factors influence the impact of the loss of 6’s?

A

Age at loss
Crowding
Malocclusion

24
Q

How does age at loss of 6’s impact the dentition?

A

Upper arch doesn’t matter
Matters more in the lower arch

Lost too late- 7 doesn’t move into it’s place
Lost too early- distal drift of 5’s.

25
Q

How does crowding impact the outcome for early loss of 6’s?

A

Crowding is desirable- best results for space closure.

If the dentition is aligned or spaced, more likely to have spaces.

26
Q

How does early loss of a central incisor influence the dentition?

A

Lost too early- drifting of adjacent teeth
Lost too late- space not closed

You would aim to keep the space open with a denture, re-implant tooth.

27
Q

What is macrodontia?

A

Tooth/teeth larger than average

28
Q

What are some issues associated with macrodontia?

A

Crowding
Asymmetry
Aesthetics

29
Q

What is microdontia?

A

Teeth smaller than average

30
Q

What are some issues associated with microdontia?

A

Leads to spacing, linked to hypodontia.

31
Q

What aspects could make a tooth abnormally formed?

A

Dens in dente
Peg shaped alterals
Fused teeth
Talon cusps
Dilaceration
Accessory cusps

32
Q

What are the most common teeth to be ectopic?

A

Third molars
Upper canines
First permanent molars
Upper centrals

33
Q

When should you palpate the buccal canine bulge?

A

9 years onwards to feel if they’re coming through.

If you cannot feel them at this age, then his would warrant further investigation.

34
Q

What are the four key aspects of clinical assessment of ectopic canines?

A

Palpation of buccal canine bulge from 9 years upwards
Mobility of c’s and 2’s
Colour of c’s and 2’s
Inclination of 2’s

35
Q

What radiographic technique would you employ to determine position of the canine?

A

OPT and upper anterior oblique occlusal.
- utilising parallax technique.

36
Q

What factors are associated with ectopic canines?

A

Class 2 division 2 malocclusions
Absent/peg shaped upper laterals

Palatal canines associated with well-aligned arches
Buccal canines associated with crowding

37
Q

What are the management options for ectopic canines?

A

Prevention
Extract c’s and encourage improvement in position of 3
Retain 3 and observe (accept position)
Surgical exposure and orthodontic alignment
Extraction (surgically)
Autotransplantation

38
Q

What are the management options for an ectopic first molar?

A

Reversible before the age of 8

Separator
Attempt to distalise 6
Extract e

39
Q

What could be the possible causes of an ectopic upper central incisor?

A

Supernumerary- tuberculate or odontome.
Trauma to primary tooth
- ankylosis of primary tooth
- Displacement of tooth germ
- Dilaceration of root

40
Q

What is transposition?

A

Interchange in the position of two teeth.

41
Q

What teeth are most commonly transposed?

A

Upper canines and first premolar
Lower canine and incisors

42
Q

What are the clinical signs of a thumb sucking habit?

A

Proclaimed upper incisors
Retroclined lower incisors
Localised AOB or incomplete OB
Unilateral posterior cross bite due to narrow maxillary arch.

43
Q

What might a prominent labial frenum cause?

A

Midline diastema.

44
Q

Why might you want to do a balancing extraction?

A

Maintain the position of the dental centreline.

45
Q

Why might you want to do a compensating extraction?

A

Maintain the buccal occlusion.

46
Q

What is the consequence of early loss of deciduous teeth?

A

Localised crowding.

47
Q

Which primary teeth require balancing extractions?

A

c’s and d’s

48
Q

What conditions are associated with supernumeraries?

A

Cleft lip and palate
Down’s syndrome
Cleidocranial dysplasia
Gardner’s syndrome

Orthodontics (15 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions