Class I Malocclusion

Question 1

Aetiology of crowding

Imbalances in…

Answer 1

Jaw size
Tooth Size
Arch perimeter
Reduction in size of jaws

Question 2

Solving crowding

Answer 2

Expansion - anterior, posterior (distal)
Distal movement
Enamel stripping
Extraction

Question 3

Expansion e.g posterior crossbite

Methods

Answer 3

Widen upper arch

Bring incisors forward

Question 4

Problems with expansion

Expansion to treat crowding

Answer 4

Relapse if over expanded
Fenestration of labial plate
Aesthetics
Schwarz appliance not good to expand lower arch

Question 5

Relapse is

Answer 5

Inevitable by 50% in most cases

Expansion of arches is not very stable

Question 6

Relapse - Non-extraction arch development

Answer 6

10% long term success

Question 7

Relapse - Premolar extractions

Answer 7

30% long term success

Question 8

Limits of expansion
Canines
Incisors
Breadth

Answer 8

0mm
2mm
3mm

Question 9

Fenestration of labial plate

Answer 9

Over expansion may lead to roots moving past plate

Question 10

Aesthetics

Answer 10

Lip support - thin - non extraction

Full lips and protruded incisors - think about extraction

Question 11

Distal movement

give e.g

Answer 11

Retract upper 6 and 7 if erupted
Retract premolars and canine
Align canine

Question 12

Distal movement of upper arch methods

Answer 12

Headgear
Non-compliance appliances
temporary anchorage devices

Question 13

Distal movement in lower arch

Answer 13

Lip bumper

Question 14

Non compliance appliances

Answer 14

Pendulum

Distal jet

Question 15

Distal movement of upper buccal segments

Answer 15

Well aligned lower arch 
Half unit class II molars

Question 16

Lower arch

Answer 16

Lip bumper

Doesn’t work

Question 17

Enamel stripping/interproximal reduction

Answer 17

Remove up to 0.25mm enamel from contact points

Question 18

Extraction

Answer 18

Most common solution

Question 19

Spacing - 3 issues

Answer 19

Midline diastema
Generalised spacing
Missing teeth

Question 20

Midline diastema

Answer 20

Mesial movement

Question 21

Generalised spacing

Answer 21

Difficult if associated with missing teeth

Question 22

Missing teeth e.g missing laterals
Options
Take into account

Answer 22

May be restorative issue
Open space
Close space
Restorative replacement
Malocclusion 
Molar relationship 
Space.

Question 23

Missing lateral incisors
Class II
Class III

Answer 23

Close space

Open space

Question 24

Displaced teeth

Most common is?

Answer 24

Upper permanent canine

Question 25

Displaced maxillary canines result from

Answer 25

Palatal impaction

Buccal impaction

Question 26

Procedure for palatal impaction

Answer 26

Leave and monitor
Extract
Expose and align
Transplant

Question 27

Procedure for buccal impaction

Answer 27

Closed exposure (attach gold chain and bring down) 
Open exposure (apically reposition flap)