Interceptive Extractions Of Permanent Teeth Flashcards
What are serial extractions?
- These were popular previously but not anymore
- intention was to transfer incisor crowding from 3 region to 4 to maximise spon alignment
- the extraction sequence was C, D, 4’s
The ideal case was class 1 with moderate crowding however few patients are ideal
Why do we perform interceptive extraction of permanent teeth?
-To guide and permit the eruption of teeth and provide relief of crowding
What is the problem with extracting 6’s ?
Halves the prognosis and double the treatment time
What indicates poor prognosis for 6’s?
Gross caries Hypoplasia Large restoration Recurrent caries Lingual or buccal caries
What is the success of extraction of 6’s dependant on?
- Timing
- Degree of crowding
- the tooth extracted (upper or lower)
- Type of malocclusion: molar relationship
At what age is the best age to xla 6’s?
When the bifurcation of the 7’s are forming and when the tooth is just below the surface of the overlying bone
What happens when the 6 is extracted too early?
Risk of 5 escaping Distally and impacting against the 7
What happens when then 6 is extracted too late ?
Space closure will be incomplete and involving more tipping of the 7
What circumstances can you change the timing of extractions?
Lower 7’s appear Distally angulated
Premolar crowding is present
What happens if the dentition is spaced?
There will be no spontaneous space closure as Dentition is already spaced
Which arch upper or lower does better following extraction of 6’s?
Lower arch does worse in terms if final 5-7 contact
What is the effect of later extractions on upper molars?
This doesn’t have too much of an effect since the upper 7’s are Distally angulated anyway
T/f
Upper molars converge?
F
They diverge
T/f Lowe molars converge?
T
Would you balance 6’s?
No! This is when you take the same tooth out on the opposite side of the arch for centreline preservation
