Week 3 Flashcards
How many mm of crowding is there in a moderate generalized space discrepancy? (Per Arch)
4mm (including leeway space)
How important is retention with space creation?
Vital. Prognosis and stability are unknown.
How much space would be gained if you extracted two premolars?
14 mm
How much space is created via Arch Expansion?
4mm
What must be considered before arch expansion?
Already protrusive?
Sufficient keratinized tissue?
Would Overjet and overbite allow it?
Who are the best candidates for Arch Expansion?
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.
When are Lingual Arch’s indicated?
Pro’s and cons
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
When are lip bumpers indicated?
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
When would you band and bond the teeth to create space?
When ROTATION is required.
Lower anterior crowding (4mm)
Tipping and bodily movement also possible (no midline adjustment is doable)
When is headgear indicated for space creation? How does it work?
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.
At what point does the crowding become too much for arch expansion?
More than 4 to 5 mm of crowding. Extraction comes into play, especially when the patient is already protrusive
What is serial extraction and when is it indicated?
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
What is the usual sequence of serial extraction?
- Remove primary canines. Allows alignment of teeth.
- When 1/2-2/3 of perm premolars root is formed, extract primary molars. (Expedited eruption of premolars.
- Extract the first premolars to provide space for permanent dentition.
What are the pros and cons of serial extraction?
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
What is localized space shortage treatment?
Space regaining of up to 3mm of space that was lost. if regained, treatment is predictable and stable.
Common causes of localized space loss
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.
What’s a quick way to fix a minor catching of the perm molar eruption on the primary molars?
Brass wire or a separator
What is a band and spring and when is it indicated?
What is a modified band and spring?
What is a bonded spring?
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.
What treatment is indicated by primary 2nd molar loss (and subsequent loss of space) caused by the eruption of the maxillary molar?
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.
What unwanted movement happens with banded and bonded fixed devices for space regaining?
Reciprocal rotation.
What makes a lingual Arch ineffective for space regaining?
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.
What type of treatment is required when there is greater than 3mm per quadrant that needs to be regained?
Palatal/incisor anchorage (nance, TADs)
Headgear
Extraction of permanent teeth
What two criteria do you need for space maintenance?
Adequate space
Tooth loss
When does a tooth begin active eruption?
When 1/2 to 2/3 of the root is formed
