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Flashcards in ORTHO Deck (64)
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1
Q

______ brackets have a special locking mechanism incorporated and they engage the archwire in the slot.

A

Self-ligating

This mechanism eliminates the need for a ligature placement. It is purported that these systems shorten treatment time by reducing friction and because the wire is efficiently kept engaged in the bracket slot.

2
Q

T/F. A large maxillary midline diastema >2mm is not likely to close spontaneously and a fixed appliance may be indicated.

A

TRUE.

A large space may indicate a supernumerary tooth or mesiodens, or missing lateral incisors.

3
Q

Major causes for orthodontic relapse include:

A
  • continued unfavorable growth
  • tissue rebound.

Relapse may occur in patients who continue to grow in the original pattern that caused the initial malocclusion. These tissues tend to rebound towards their original state.

4
Q

In which direction are the forces of the high-pull headgear directed?

A

Superior and DIstal

Max M1s

5
Q

What head gear would you use to correct a class III?

A

Reverse pull headgear/facemask/ protection headgear

6
Q

______ is a load applied to an object tending to move it

A

Force

7
Q

______ is the point where opposition to movement is concentrated

A

Center of resistance

8
Q

_______is The tendency of an object to rotate around a point

A

Moment -

9
Q

Define couple :

A

Two forces equal and opposite

10
Q

The most common cause of a lateral shift into crossbite is the ______________.

A

constriction of the maxillary arch

The dental interferences created by such a constriction cause the mandible to shift into the crossbite position.

Several appliances may be used for this purpose, including a quad helix, a W-arch appliance.

11
Q

Which facial type is considered an average mandibular plane angle of 32 +/- 4?

A

Mesofacial

Mesofacial will have an average mandibular plane angle of 32 +/- 4, straight profile, ideal growth pattern (down and forward) and normal anterior face height.

12
Q

ANB =

A

ANB = 2 degrees +/- 2 degrees (0 to 4)

ANB angle measures the relative position of the maxilla to mandible. The ANB angle can be measured or calculated from the formula: ANB = SNA - SNB. A positive ANB angle indicates that the maxilla is positioned anteriorly relatively to the mandible (Class I or Class II malocclusion cases).

13
Q

Bucco-lingual movements are _____ movements.

A

third-order

tipping of the root

14
Q

_______ is the lowest point on the mandibular symphysis.

A

The Menton

15
Q

1

A

1

16
Q

1

A

1

17
Q

1

A

1

18
Q

1

A

1

19
Q

Second-order movements include ____1___and ____2___ movements.

A
  1. mesio-distal ( root tipping)

2. vertical ( occlusogingival)

20
Q

1

A

1

21
Q

1

A

1

22
Q

1

A

1

23
Q

______ is the most posterior inferior point on the angle of the mandible. This point can be “guesstimated”, or determined more accurately by bisecting the angle formed by the tangents from the posterior border of the ramus of the inferior border of the mandible.

A

Gonion (Go)

24
Q

SNB =

A

80 degrees +/- 2 degrees (78 to 82)

25
Q

1

A

1

26
Q

1

A

1

27
Q

1

A

1

28
Q

1

A

1

29
Q

Three facial types exist and they include:

A

Mesofacial, Brachyfacial and Dolichofacial.

30
Q

1

A

1

31
Q

Brachyfacial types will have:

A
  1. A low mandibular plane angle of<28,
  2. concave profile
  3. horizontal growth pattern
  4. short anterior face height
  5. Class II Division II deep bite.
32
Q

Orthodontic ( __1__) or orthopedic (2) forces placed on a tooth will induce remodeling.

A
  1. light
  2. heavy

Sustained forces applied to a tooth will cause a pressure side and tension side to occur.

33
Q

The _____ will be found on the side the tooth is being moved into, which will have a decrease in blood flow, increased osteoclast activity, and bone removal.

A

pressure side

34
Q

T/F. An SNA plane relates the position of the maxilla compared to the cranial base.

A

TRUE

SNA = 82 degrees +/- 2 degrees (80 to 84)

An SNA plane relates the position of the maxilla compared to the cranial base.

35
Q

Horizontal movements are _____ ____movements.

A

First-order

Rotation around the long axis of the tooth

36
Q

_____is the most anterior point on the mandibular symphysis.

A

Pogonion (Pog)

37
Q

1

A

1

38
Q

_______ is the uppermost, outermost point on the bony external auditory meatus.

A

Porion( Po)

39
Q

An SNA > 84 degree angle would indicate a _____ patient while an SNA <80 degree angle indicates a _______ patient.

A
  1. prognathic
  2. retrognathic
SNA = 80-84
SNB= 78 - 82
ANB = 0-4
40
Q

_______is the line connecting the midpoint of sella turcica with nasion.

A

SN line:

Is taken to represent the cranial base.

41
Q

1

A

1

42
Q

1

A

1

43
Q

1

A

1

44
Q

Arch bar, ivy loop wiring, and continuous loop wiring are all types of _______.

A

IMF - intermaxillary fixation

45
Q

Some facial characteristics
elongation of the lower third of the face
a narrowed nose
lip incompetence
excessive incisive gingival display. Can be seen in what condition?

A

vertical maxillary excess

46
Q

The most posterior, inferior point on the gonial angle at the junction of the ramus and body of the mandible is:

A

Gonion.

This point can be “guesstimated”, or determined more accurately by bisecting the angle formed by the tangents from the posterior border of the ramus to the inferior border of the mandible.

47
Q
pt EOE shows :
-  a high mandibular plane angle >36,
-  convex profile
- vertical growth pattern, 
- long anterior face height
- an anterior open bite tendency
WHat facial type is this pt?
A

Dolichofacial

48
Q

SNA =

A

82 degrees +/- 2 degrees (80 to 84)

49
Q

1

A

1

50
Q

________ is the line joining porion and orbitale.

A

The Frankfort plane

This plane is difficult to define accurately because of the problems inherent in determining orbitale and porion.

51
Q

1

A

1

52
Q

1

A

1

53
Q

______ is used to correct deficiencies of the mandible and maxilla. The procedure involves creating an osteotomy by which gradual tension is placed on the separated segments. This tension slowly separates the segments and allows new bone to grow between them.

A

Distraction osteogenesis

Because of the speed of this procedure, the body has time to also build blood vessels and produce adaptations in the surrounding nerves, connective tissues, bone and skin.

54
Q

1

A

1

55
Q

1

A

1

56
Q

Pogonion (Pog) is __________

A

the most anterior point on the mandibular symphysis.

57
Q

1

A

1

58
Q

1

A

1

59
Q

________is the lowest point on the mandibular symphysis.

A

Menton (Me)

60
Q

1

A

1

61
Q

1

A

1

62
Q

Porion (Po) is the

A

uppermost outermost point on the bony external auditory meatus.

63
Q

1

A

1

64
Q

1

A

1