Class 3 Malocclusion

Question 1

Definition of class 3

Answer 1

Lower incisor edge occludes anterior to cingulum plateau of upper central incisor
OJ is reduced or reversed

Question 2

A/P skeletal cause of class 3

Answer 2

• small maxilla
• large mandible
• combination of both
• usually class 3 skeletal base relationship

Question 3

Vertical skeletal cause of class 3

Answer 3

• Associated with average, increased or reduced vertical proportions: FMPA, facial height, lat ceph
• Increased FMPA and AOB more complex to treat