Extractions As Part Of Treatment Flashcards
Which type of incisor orthodontia problem needs soace creation to be corrected?
Overjet reduction
When would we extract teeth in ortho?
- Crowing
- Space to correct incisor relationship
- Provide anchorage to move teeth
If you were reducing an overjet by 5mm how much space would need to be created?
10mm
1mm:2mm space
Why would you extract upper teeth rather than prolonging lower incisors to correct overbites?
Upper incisor retraction is more stable than proclaiming lower labial
Risk of perforating buccal plate in lower labialise segment which means perio problems
What happens when you being to move teeth into spaces that have been created by extraction?
- Movement of desired teeth
2. Movement of anchor teeth
If you do not have enough anchorage from the teeth and intro oral sites what could you do?
Head gear
What are the factors which influence the choice of teeth to be extracted?
- Dental health of the tooth
- Future Stability
- Amount of space and anchorage needed
- Labial vs molar
What factors about future stability must be avoid when extracting teeth?
Do not want to later AP direction of incisors
Do not want to expand the arch
T/F
Extracting teeth closer to the problem area crates less anchorage
F
What is the problem with xla labial segment teeth?
Aesthetically important
What is the problem with xla molars?
Generally too far forward from where the problem lies
What are the advantage the advantages of xla premolars?
- Space near the front which is where most problems are
- Contact or residual space which is dentally healthy if no active treatment is carried out
- Permits good occlusal fit
Which arch should be planned first?
Lower arch
How much crowding would be mildly crowded?
1-4mm
How much crowding would be moderate crowding?
5-9mm
How much crowding would be 9+ mm?
Severe
Which teeth would you extract in mildly crowded case?
None or 5’s
Which teeth would you xla in moderate crowded case?
5/4
Which teeth would you xla in severely crowded case ?
4
What group of factors do you need to consider before extracting?
Tie Break Factors
What are the tiebreak factors?
- Canine Angulation
- Lip prominence
- Initial incisor inclination
T/F the upper arch needs less space than the lower when planning extractions and why?
F
It needs as much space or more space because the upper anterior teeth are larger and occasionally have an overjet which needs solving
In the upper arch retroclined 3’s need more space to align?
T
Incisors that are positioned in an upright manner need more or less anchorage?
More
If you extract upper premolars and not anylower teeth how will this affect the lost relationship?
Molars finish in class 2
What is the canine rule?
Need enough space to get the cosines into class 1 relationship when the lower labial segment is well aligned
