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Flashcards in Week 3 Deck (47)
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1
Q

How many mm of crowding is there in a moderate generalized space discrepancy? (Per Arch)

A

4mm (including leeway space)

2
Q

How important is retention with space creation?

A

Vital. Prognosis and stability are unknown.

3
Q

How much space would be gained if you extracted two premolars?

A

14 mm

4
Q

How much space is created via Arch Expansion?

A

4mm

5
Q

What must be considered before arch expansion?

A

Already protrusive?
Sufficient keratinized tissue?
Would Overjet and overbite allow it?

6
Q

Who are the best candidates for Arch Expansion?

A

Needs 4mm
Skeletal and dental class 1
All teeth present clinically or radiographically - often used when canines are impacted because there’s no room for them to come in. Once the space is created they can come in naturally.

7
Q

When are Lingual Arch’s indicated?

Pro’s and cons

A

Best for lower anterior crowding
Needs up to 4mm
Facial tipping of incisors
Best for faciolingual discrepancies

NOT good for rotations
Can cause 2nd molar impaction
Stability unknown

8
Q

When are lip bumpers indicated?

A

Lower anterior crowding (4mm)
Best for faciolingul discrepancies
Facial tipping of incisors and bodily migration by interrupting the equilibrium.

Can upright the molars and cause impaction
Not for rotation

9
Q

When would you band and bond the teeth to create space?

A

When ROTATION is required.
Lower anterior crowding (4mm)
Tipping and bodily movement also possible (no midline adjustment is doable)

10
Q

When is headgear indicated for space creation? How does it work?

A

For crowding in the Maxillary buccaneers region.

Cervical pull would pull back on the molars to create space distally with some extrusion.

High pull headgear would extrude less.

Requires compliance.

11
Q

At what point does the crowding become too much for arch expansion?

A

More than 4 to 5 mm of crowding. Extraction comes into play, especially when the patient is already protrusive

12
Q

What is serial extraction and when is it indicated?

A

Serial extraction is the extraction of primary teeth to facilitate alignment of the erupted permanent teeth, and encouragement of permanent premolars to facilitate early extraction. (Get em in to get em out)

Over 10 mm of crowding
Class 1, good facial form
Early loss of primary canines
Gingival defects
Impaction imminent
13
Q

What is the usual sequence of serial extraction?

A
  1. Remove primary canines. Allows alignment of teeth.
  2. When 1/2-2/3 of perm premolars root is formed, extract primary molars. (Expedited eruption of premolars.
  3. Extract the first premolars to provide space for permanent dentition.
14
Q

What are the pros and cons of serial extraction?

A

Pros
Spontaneous incisor alignment
Improved psych
Reduced active treatment time

Cons
Incisor Lingual tipping
Requires future tipping
Remaining teeth may not erupt or have poor form

15
Q

What is localized space shortage treatment?

A

Space regaining of up to 3mm of space that was lost. if regained, treatment is predictable and stable.

16
Q

Common causes of localized space loss

A

Interproximal caries

Perm 1st molar ectopic eruption that catches on and substantially resorbs the primary molar, causing the patient to loose it and subsequently loose much of that space, sometimes beyond the ability of moderate localized space regaining treatment.

17
Q

What’s a quick way to fix a minor catching of the perm molar eruption on the primary molars?

A

Brass wire or a separator

18
Q

What is a band and spring and when is it indicated?

What is a modified band and spring?

What is a bonded spring?

A

Indicated when perm molar catching on primary molar has already caused some space loss. Band goes around the primary molar. Has a spring welded to the band that pushes the permanent molar distally

A modified band and spring skips the soldering, runs a wire through the band, loops it into a spring and cements directly to the crown of the perm molar.

A bonded spring puts a bracket on each tooth and bends a loop in between.

19
Q

What treatment is indicated by primary 2nd molar loss (and subsequent loss of space) caused by the eruption of the maxillary molar?

A

Option 1: Removable retainer with Adams clasps for retention and a spring pushing back on the permanent molar (which will go back and rotate around the thick Lingual root) Once the space is regained, hold in pace with a band and loop.

Option two: fixed Appliance with a Nance anchored in the palate in max (lingual Arch anchored on anterior teeth in mandibular), banded molars with an open cool spring to bodily move and open the space.

20
Q

What unwanted movement happens with banded and bonded fixed devices for space regaining?

A

Reciprocal rotation.

21
Q

What makes a lingual Arch ineffective for space regaining?

A

A thick heavy stainless steel wire is required to reach a sufficient force to move, so the range is very small.
Only moves a little.

22
Q

What type of treatment is required when there is greater than 3mm per quadrant that needs to be regained?

A

Palatal/incisor anchorage (nance, TADs)
Headgear
Extraction of permanent teeth

23
Q

What two criteria do you need for space maintenance?

A

Adequate space

Tooth loss

24
Q

When does a tooth begin active eruption?

A

When 1/2 to 2/3 of the root is formed

25
Q

How much space will be lost when you loose a primary anterior or canine?

A

None. It’s mostly stable.no space maintenance is required.

26
Q

Where are lower permanent tooth buds located and what does that have to do with space maintenance?

A

Permanent lower tooth buds are to the lingual of the anteriors. If you have a lingual wire trying to maintain space there, that would interrupt the natural eruption.

27
Q

When is a distal shoe used?

A

For space maintenance only when there is a missing primary second molar prior to the eruption of the perm 1st molar.

28
Q

What cautions need to be made in the use of a distal shoe?

A

Watch for dislodgment

Not for patients at risk of infective endocarditis

29
Q

What are the types of lingual Arch appliances used for space maintenance?

A

Transpalatal Arch: used when one side of the arch is broken but the other isn’t

Maxillary lingual Arch: can be used as long as overbite isn’t impinging

Maxillary nance Arch: anchors off the palate.

30
Q

Common problem with a lingual Arch in space maintenance?

A

Catching on erupting teeth

31
Q

What’s the effect of extraction prior to 1/2-2/3 succedaneous tooth root formation?

A

Slower eruption.

Opposite is also true.

32
Q

How much space is typically available from the leeway space?

A

9 mm

33
Q

What is the definition of space management?

A

Using space that you have from leeway (E-space) to fix other issues like crowding

34
Q

What must be true for space management to be successful?

A

Management must continue until transition is complete. This way, the arches have not been expanded so it is very stable.

35
Q

How is disking used to manage space during the transition.

A

Disking of the PRIMARY teeth only will free up some of the transitional crowding. Happens most on the primary canines and molars, and is followed by F varnish.

Do NOT disk perm teeth.

36
Q

What are holding arches used for?

A

Space management
Constructed with ideal arch form for alignment of anteriors in preparation for premolars to come in.
Limited tooth mover- no rotation, fat wire

37
Q

When are holding arches with selective extraction necessary?

A

When there is adequate space, but severe crowding (eg: if perm lower laterals erupted behind the primary laterals, you would extract the primary laterals and the canine to make room for the perm lateral to align via the holding arch, then the rest of the space is maintained enough for the rest of the transition to go smoothly.

38
Q

How is aging related to crowding?

A

Crowding tends to increase as we mature, especially those that started as ideal.

Hispanics have more maxillary and mand irregularly than whites or AA.

39
Q

What must be done before making a treatment plan to correct crowding?

A

A facial form analysis, radiographs, and a space analysis.

40
Q

When would you treat / leave excess space?

A

Usually No treatment, especially during transition phase. Incoming canines are likely to close some space.

Consider treatment: esthetics, risk of trauma, due to pathology

41
Q

What are two common causes of generalized spacing?

A

Big arch

Small teeth

42
Q

How do you treat generalized spacing?

A

Fixed Appliance: rectangular wire can produce bodily movement. Anchorage on the bonded teeth. Activate every 4 weeks.

Removable appliance: with labial bow. Will produce tipping. Retention from Adams clasps. Anchorage on palate. 2mm activation for 1 mm of movement

43
Q

Which ethnicity most commonly has diastemas?

A

More common in African American population.

44
Q

Causes of diastemas

A

Large arch - small teeth
Ugly duckling transition period
Supernumerary teeth
Missing teeth (laterals)

45
Q

How do you determine if a Frenum is going to interfere with diastema closure?

A

Close it and then see if a frenectomy is necessary.

Judging by the morphology ahead of time is a poor way to diagnose.

46
Q

How do you close a diastema?

A

Hawley with two finger springs activated 2mm each to get 1mm per month. Will produce tipping but sometimes that’s appropriate.

Fixed: when tipping would be unaesthetic. either round or rectangular wire is acceptable because you only need mesial-distal bodily movement

Both need lingual retainers for retention.

47
Q

How do you calculate the Tanaka Johnson Space Analysis?

A

PER QUADRANT: Width of the mand. Central and lateral plus 10.5 = width of mandibular canines and premolars

Width of the mand. Central and lateral plus 11= width of maxillary canines and premolars