Molar Incisor Hypomineralisation

Question 1

Name the cells that form enamel

Answer 1

Ameloblasts

Question 2

What is the stimulus that causes ameloblasts to start making enamel

Answer 2

Dentine deposition which causes ameloblasts to retreat from the ADJ

Question 3

What do Amelobalsts do

Answer 3

They secrete matrix protein that calcify immediately

This forms enamel

Question 4

Apart from matrix secretion what else do ameloblasts of

Answer 4

They secrete enzymes that remove the organic component and allow full mineralisation of the matrix proteins

Question 5

What problems can occur with enamel deposition

Answer 5

1. Hypoplastic enamel

2. hypomineralsition

Question 6

What causes Hypoplastic enamel

Answer 6

Physical disruption during the laying down of the enamel matrix

Question 7

What causes hypomineralsition

Answer 7

Can occur either int eh calcification stage or in the maturation stage

Question 8

How can the classification of enamel defects be split

Answer 8

1. Systemic

2. local

Question 9

What can cause localised enamel defects

Answer 9

1. Trauma

2. Infection

Question 10

What can cause systemic enamel defects

Answer 10

1. Genetic

2. Environmental cause

Question 11

What is the only genetic condition that can lead to enamel defects

Answer 11

Amelogenisis imperfecta

Question 12

What can environmental systemic enamel defects be split into

Answer 12

1. Chronological defect

2. Generalised defect

Question 13

Give an example of a generalised environmental enamel defect

Answer 13

Fluorosis

Question 14

Give an example of a chronological environmental enamel defect

Answer 14

Molar incisial hypomineralisation

Question 15

What terms can we use to describe enamel defects

Answer 15

1. Demarcated
2. Diffused
3. Hypoplastic

Question 16

What does demarcated mean when referring to enamel

Answer 16

1. Distinct, clear boundaries

2. Yellow, white or brown in colour

Question 17

What does diffused mean when referring to enamel

Answer 17

1. No clear boundaries

2. Lines, patchy or confluent areas

Question 18

What does hypoplastic mean in terms of enamel

Answer 18

Loss of enamel

Pits or grooved present

Question 19

How do we describe enamel suffering from molar incisor hypomineralisation

Answer 19

Demarcated

Question 20

How do we describe enamel suffering from fluorisis

Answer 20

Diffused

Question 21

How do we describe enamel suffering from localised enamel defects

Answer 21

Hypoplastic

Question 22

How do we describe enamel suffering from amelogensis imperfect

Answer 22

Demarcated, Diffused and hypoplastic

Question 23

What is molar incisor hypomineralisation

Answer 23

hypomineralisation of systemic origin of one or more first permanent molars as well as any associated and affected incisors

Question 24

What are other terms used to describe MIH

Answer 24

1. Molar hypomineralisation
2. Incisor hypomineralisation
3. Deciduous molar hypomineralisation

Question 25

What does the term hypomineralised mean

Answer 25

A disturbance of enamel formation resulting in a reduced mineral content

Question 26

What does the term hypoplastic mean

Answer 26

Reduced bulk or thickness of enamel | Enamel NEVER formed

Question 27

If enamel is a brownish/ yellow colour what does that indicate

Answer 27

It is most porous

Question 28

If enamel is a whitish/ yellow colour what does that indicate

Answer 28

It is less porous

Question 29

What problems can hypomineralsed molars cause

Answer 29

1. Post eruptive breakdown 2. Can be sensitive 3. Teeth are more susceptible to caries 4. Teeth decay faster 5. Teeth are more difficult to restore

Question 30

How common is MIH?

Answer 30

5-25%

Question 31

How do we treat MIH

Answer 31

1. Start with molars and think about prognosis

Question 32

What do we think about when forming long term diagnosis for MIH molars

Answer 32

1. Multi surface defects 2. Brown/yellow defects 3. Is there evidence of post eruptive breakdown 4. Is there pain/ sensitivity 5. Is the defect extending across cusps or marginal ridges 6. Caries

Question 33

What considerations do we need to take before extraction permanent molars

Answer 33

Orthodontic considerations

Question 34

Describe the ideal orthodontic situation when considering the removal of a permanent molar

Answer 34

1. Class I occlusion 2. Normal/ reduced overbite 3. Mild to moderate crowding 4. Minimal anterior crowding 5. All permanent teeth present

Question 35

At what age is ti best to carry out lower permanent molar extraction

Answer 35

8-9

Question 36

At what age is ti best to carry out upper permanent molar extraction

Answer 36

Timing less critical but the space is likely to close if the molar is extracted before 11/12 yrs

Question 37

When extracting permanent molars we also need to what

Answer 37

Compensate for iver eruption

Question 38

How do we compensate for overruption when extracting a lower 6

Answer 38

Extract the upper 6 as well as it will most lilt over erupt and cause unfavourable occlusion

Question 39

How do we compensate for overruption when extracting an upper 6

Answer 39

We don't need to compensate

Question 40

Do we extract every MIH affected permanent molar

Answer 40

NO we can restore/ conserve

Question 41

How can we restore/ conserve an MIH affected molar

Answer 41

1. Tooth mousse 2. Fissure sealant 3. Amalgam 4. GIC 5. Composite 6. SSC 7. Onlays

Question 42

Why might we use tooth mousse

Answer 42

If the patient has sensitivity

Question 43

What conditions must be fulfilled before we place fissure sealants

Answer 43

1. Enamel is intact ad of good hardness 2. No sensitivity 3. Bitewings demonstrate no caries

Question 44

Do we regularly place amalgam on primary teeth

Answer 44

no

Question 45

what options do we have to restore incisors

Answer 45

1. Microabrasion 2. Bleaching 3. Resin infiltration 4. Composite veneers 5. Porcelain veneers