tx of class II

Question 1

What is class II incisor relationship?

Answer 1

Lower incisor occludes behind upper incisor cingulum plateau

Div 1- proclined upper
Div 2- retroclined upper

Question 2

How does the age of the pt affect the tx?

Answer 2

Growing pt- functional appliance great at reducing OJ + ortho camouflage

Non growing pt- ortho camouflage + orthognathic surgery

Straight wire appliance poor at reducing OJ

Question 3

What functional appliance tx is there?

Answer 3

Activators (mild non crowded cases)
Twin block appliance (severe/crowded cases)

Question 4

What is a medium opening activator?

Answer 4

Good for mixed dentition- no rigid appliance where there are loose teeth

Single unit, postures bite

Acrylic flanges joined to acrylic coverage of lower incisors

Question 5

What is the twin block?

Answer 5

2 piece functional appliance
Upper and lower bite block
Pt can open and close
Postures mandible forward
Two blocks rest together
Adam clasps on 4s and 6s
Ball ended clasps
7-8mm inclined plane
Full time wear
Can cause lateral open bite, corrected w fixed

Question 6

What is ortho camouflage?

Answer 6

Fixed +/- extractions
Relies on anchorage (control of unwanted tooth movement)
Loss in anchorage= lack of occlusion in buccal segment and residual OJ

Question 7

What are the keys to planning anchorage?

Answer 7

Lower arch crowding
Molar and canine relationships

Question 8

How can you reinforce anchorage?

Answer 8

Headgear (holds 6 in place)
Palatal arches (anchors molars)
Implants (doesn’t move like teeth so stays in place, midline palatal, miniscrew)
Class II elastics (used lower arch as anchor)

Question 9

How can you correct half unit class II molars?

Answer 9

Non extraction- distal movement w headgear
Extract upper 7s for distal movement
Extract upper premolars to bring molar forward into full unit class II (stable)

Question 10

If there is lower crowding how do you manage to class II incisor relationship?

Answer 10

Molar class I- upper and lower 4s/5s

Molar class II half unit- upper and lower 4s/upper 4s and lower 5s

Molar class II full unit- upper and lower 4s/5s (severe anchorage problems- needs to become class I)

Question 11

How do you treat class II div 2?

Answer 11

Treat over bite
Comprehensive tx (functional and fixed appliances)