Impacted third molars (8s)

Question 1

What % of people between 20-30 will have one impacted third molar?

Answer 1

Around 70%

Question 2

Give the two ways third molars are classified:

Answer 2

1. The degree of eruption
2. The angulation and position

Question 3

How are third molars classified by Pell & Gregory degree of eruption?

Answer 3

1. Erupted
2. Partially erupted
3. Unerupted

Question 4

What are the typical orientations of third molars (give 4 examples):

Answer 4

1. Vertical
2. Horizontal
3. Disto-angular
4. Mesio-angular

Question 5

What is the most common cause of therapeutic 3rd molar removal?

Answer 5

Pericoronitis

Question 6

What radiograph should be taken to assess 3rd molars and why?

Answer 6

OPG in order to see how close 8s are to inferior alveolar nerve

Question 7

What is the radiographic assessment acronym for 3rd molars?

Answer 7

A = Angulation
R = Root morphology
M = Margin of bone
H = Height of tooth in bone
I = ID canal
T = Trabeculation of bone

Question 8

Give 6 post-op. instructions for removal of 8s:

Answer 8

1. Pain - use paracetamol NOT aspirin as it can promote bleeding
2. Swelling - increases up to 48 hours
3. Trismus
4. Bruising
5. Soft diet
6. Fluids and rest

Question 9

List 5 complications of 8s removal:

Answer 9

1. Haemorrhage
2. Infection
3. Haematomas
4. Jaw fracture
5. Damage to adjacent structures