Extractions in Orthodontics Flashcards
How to create space (expansion) without extractions?
Expand arch - laterally, anteriorly, posteriorly
What does anterior movement cause?
Bimaxillary proclination
What is the problem with bimaxillary proclination?
Appearance
stability
periodontal health
Reasons for extractions in ortho?
Relieve crowding Correct incisor relationship - Reduce overjet (remove upper 5s) - Camouflage in class III (remove lower teeth) Overbite correction Correct centrelines Anchorage
Principles of extractions in ortho?
- Condition of teeth
- Location of crowding
- Position of teeth (crowns/apices)
- Appliance treatment proposed (pt attitude)
Relating to the condition of the teeth, which should be extracted?
Ones with a poor prognosis
What to do when there’s loss of the upper central incisor?
Preserve space
Close space - crown lateral incisor or build it up by moving the lateral incisor across
When to extract central and lateral incisors?
Centrals:
Rarely indicated
If poor prognosis
Laterals:
Poor prognosis
For symmetry
Severely displaced
Which teeth are most commonly extracted for ortho?
Premolars
What’s a compromised extraction method?
Take out teeth that we have to take out (carious) when we would prefer to take out other teeth
We prefer to keep upper 3-3 for aesthetics
Why extract teeth close to crowding?
Class III camouflage
Relief of crowding
LR2 displaced
What are the problems with lower incisor extractions?
Compromise the occlusion
Increased overjet and overbite
Increased upper crowding
Why extract canines?
Gross displacement Quicker treatment (than alignment if ectopic)
Problems with canine extractions?
Upper arch
- Space between 2 and 4 opens
- Poor aesthetics
Lower arch
- poor contact between 2 and 4
Why extract 1st premolars?
Good anchorage balance
Retract anterior teeth
Bring posterior teeth forward
