tx of class I

Question 1

What is a class I incisor relationship?

Answer 1

British standard classification

Lower incisor occludes at or below the upper incisor cingulum plateau

Question 2

What class I malocclusion problems can occur?

Answer 2

Crowding (imbalance in jaw/tooth size or arch perimeter)
Spacing
Displaced teeth (usually canine)

Question 3

How do you treat crowding?

Answer 3

1. Expansion
2. Distal movement
3. Enamel stripping
4. Extraction

Question 4

What are problems with expansion?

Answer 4

Relapse
Fenestration of labial plate
Aesthetics

The limits of expansion- 2mm anteriorly, 0mm canines, 3mm in the molars

Question 5

How is distal movement achieved?

Answer 5

Upper arch- headgear (+FA, URA, TB), temporary anchorage devices (screw in bone acts as anchor), non compliance appliances (pendulum/distal jet)
- only works w well aligned lower arch, cooperative pt, no more than half unit correction

Lower arch- lip bumper

Question 6

How does enamel stripping work?

Answer 6

Aka interproximal reduction

Abrasive metal strips or air rotor stripping
Remove up to 0.25mm enamel from contact points
Can cause sensitivity
Not advised for younger pts

Question 7

What types of spacing are there?

Answer 7

Upper midline diastema
Generalised spacing
Missing teeth

Question 8

How are missing laterals managed?

Answer 8

Open or close space?

Depends on malocclusion, molar relationship and space present

Often if class II- close, class III- open

Question 9

What percentage of maxillary canines are displaced buccally?

Answer 9

Buccal- 15%
Palatal- 85%

Question 10

How should you manage a palatally placed canine?

Answer 10

1. Leave in situ and monitor
2. Extract
3. Expose and align
4. Transplant

Question 11

How should you manage buccally placed canines?

Answer 11

Open exposure- apically repositioned flap

Closed exposure- gold chain attached