The first permanent molar in orthodontics

Question 1

Loss of first permanent molars

Answer 1

Age 8 1/2 to 10-years-old
Class I occlusion
Mild incisor crowding
All permanent teeth present

Question 2

Implications for loss of first permanent molars

Answer 2

Disturbs occlusion
-especially if lower arch extraction
Orthodontic treatment prolonged
-high caries rate
-doubtful cooperation
Treatment may be more difficult
Patients unsuitable

Question 3

Problem of first permanent molar

Answer 3

Geographical inequality

Socio-economic group inequality

Question 4

Proportions of children with obvious dental decay experience in permanent teeth

Answer 4

Higher in 15yo than 12yo

Higher in NI than England

Question 5

Caries rates

Answer 5

Higher in socio-economic gps IV and V

Question 6

Extraction of first permanent molars factors influencing success/ that you need to consider

Answer 6

Degree of crowding/ hypodontia
-uncrowded vs crowded arches
Upper or lower
Timing of extraction
Balancing or compensating extractions

Question 7

First molar extraction - upper or lower?

Answer 7

Due to different eruption paths

• upper 6 rarely a problem
• lower 6 is problem:
  1. tilts mesially
  2. rotates mesio-lingually
  3. leans lingually
  4. over-eruption of upper 6

Question 8

Occlusal problems: over-eruption

Answer 8

If upper 6 over-erupts, it will stop any mesial movement of lower 7

Question 9

One or more poor quality first permanent molars

Answer 9

Immediate extraction?
-symptomatic
-unrestorable
-little scope for mesialisation o 7
-ortho Rx unlikely
Retain - ortho later?
-6s of poor prognosis

Question 10

Ideal time to remove lower 6s

Answer 10

Dentine bifurcation of 7s visible
Possible other favourable factors:
-lower 5 engaged in bifurcation of E
-lower 7 mesially angulated
-lower 8 present

Question 11

One or more poor quality first molars

Answer 11

1. Will pt need ortho?
   - yes: refer for early opinion
2. Will the affected tooth require a crown ro RCT in future?
   - yes: consider extraction
3. Consider extraction of other first molars

Question 12

Balancing/ compensation

Answer 12

Balancing: extraction in the same arch on the opposite side
Compensating: extraction in the opposite arch on the same side
-do not balance 6s
-consider extraction of upper molar if lower is extracted

Question 13

Take care with extraction - alveolar necking

Answer 13

Lots of cortical bone in between after extraction

Question 14

Consideration of the malocclusion - class II

Answer 14

• Extract first molars early
• Correct Class II with functional appliance OR
• Maintain and incorporate into ortho Rx

Question 15

Consideration of the malocclusion - class III

Answer 15

Seek opinion, orthodontic treatment can be
delayed to assess mandibular growth. Timing
of extraction can alter if orthognathic surgery is
planned

Question 16

Advantage of taking out 6s

Answer 16

Usually prevents impacted 8s but not always

Question 17

What age is best to extract upper first molars?

Answer 17

9 years 4 months