Molar- incisor hypomineralisation Flashcards
Define and describe molar- incisor hypomineralisation
- Occurs due to systemic reasons
- May affect one, two, three or all four first permanent molars. This is seen in association with affected incisors
- It seen as enamel opacities which has different colours
- Sometimes, the enamel may breakdown (post eruptively)
- The main feature of MIH is that there is a demarcation between affected and sound enamel
- It present asymmetrically; one side of the mouth may have severe MIH while the other side of the mouth may be sound, or have only minor defects
Discuss the aetiology of molar- incisor hypomineralisation (7)
- It has multifactorial aetiology
- Several harmful agents/conditions may act together and increase the risk of MIH occurring additively or even synergistically
Examples include: • Environmental contaminants • Birth complications • Medical problems during pregnancy • Early childhood issues • Dental trauma and postnatal problems/diseases during the first year of life • Medications like amoxicillin • Genetics
Describe the way MIH may impact patients
MIH may impact on the wellbeing of young patients
List the 6 associated difficulties in treating MIH-affected teeth
- Hypersensitivity
- Anxiety
- Difficulties with anaesthesia
- Poor aesthetics
- Carious lesions with fast progression
- Failure of restorations
Identify the differences between hypomineralised and hypoplastic enamel, and state in which stage of tooth development MIH and hypoplasia occur.
Differences:
• Enamel hypoplasia: a quantitative defect which occurs during the secretion phase. There is not enough enamel.
• Enamel hypomineralisation: a qualitative defect which in either the calcification or maturation phase. There is something wrong with enamel
Stages in which they occur:
• Amelogenesis is known as the process of enamel formation during tooth development. There are to main phases in amelogenesis, the secretory phase and the maturation phase
• MIH: maturation phase
• Hypoplasia: secretory phase
Is MIH a type of amelogenesis imperfecta?
- No. They are NOT the same thing
- Amelogenesis imperfect is a hereditary abnormality which affects the permanent dentition
- It usually presents symmetrically and affects ALL teeth
- MIH produces asymmetrical defects, and only affects the permanent first molars and incisors
Discuss the environment as an aetiology of MIH
- Study showed that urban children had close to double the prevalence of MIH compared with their rural counterparts
- This indicated that environmental contaminants such as BPA might be involved
Discuss birth complications as an aetiology of MIH
- A recent study demonstrated a positive association between risk for MIH and infant hypoxia and caesarean section
- Moreover, there is a link between smoking late in pregnancy and HSPM (Hypomineralised second permanent molars)
- However, the literature is conflicted on whether peripartum events such as premature birth, caesarean birth and birth complications cause MIH
Discuss early childhood complications as an aetiology of MIH
- There is an association of MIH with early childhood fever and “respiratory disease”, which includes pneumonia and asthma
- High dose Vitamin D supplementation in pregnant women may reduce the prevalence of MIH significantly
Discuss medications as an aetiology of MIH
• No specific drugs can be identified as causing MIH at this time
State the name of the old criteria used to diagnose MIH, and describe how it worked in terms of scores for:
- Individual teeth
- The entire dentition
Known as EAPD Defect diagnosis criteria. Works off of a scoring system where characteristics are given a score
Teeth:
• Mild: score between 3- 6
• Moderate: scores between 7- 9
Entire dentition:
• Mild: scores between 5- 20
• Moderate: scores between 21- 36
• Severe: scores between 37- 52
For the EAPD criteria, provide descriptions for what is considered to be
- Mild MIH
- Severe MIH
Mild MIH:
• Demarcated enamel opacities WITHOUT enamel breakdown
• Occasional sensitivity to external stimuli
Severe MIH:
• Demarcated enamel opacities WITH breakdown
• Caries
• Persistent/spontaneous hypersensitivity
State the name of the new criteria used for diagnosing MIH, and how it is used to inform treatment options
2017 index Weerheijm et. al. criteria
It informs treatment options through the formation of a treatment need index (which has 4 index).
Using this index, the caries risk of the tooth is assessed. Then, based on the caries risk, a treatment flow chart is used to determine the appropriate treatment.
Describe the 4 indexes of the Weerheijm et. al. criteria
Index 1:
- Only demarcated opacities
- No hypersensitivity or enamel breakdown
Index 2:
- Demarcated opacities WITH enamel breakdown
- No hypersensitivity
Extent of opacities:
2a: Less than 1/3 enamel affected
2b: More than 1/3 enamel affected, but less than 2/3 affected
2c: More than 2/3 enamel affected
Index 3:
- Demarcated opacities WITH hypersensitivity
- NO enamel breakdown
Index 4:
- Hypersensitivity AND enamel break down
Extent of opacities:
4a: Less than 1/3 enamel affected
4b: More than 1/3 enamel affected, but less than 2/3 affected
4c: More than 2/3 enamel affected
List the 6 treatment options that the Weerheijm et. al. provides that Oral Health Professionals can use for hypomineralised teeth
- Therapy A: Fluoride prophylaxis for remineralisation at home (CPP-ACP) or in clinics (varnish)
- Therapy B: Using different sealant materials like adhesives, flowables or low viscosity GIC
- Therapy C: Short term temporary restorations with GIC or GIC and orthobond
- Therapy D: Stainless steel crown as a long term temporary restoration
- Therapy E: Permanent restorations either direct composite or indirect restorations
- Therapy F: Extractions of the teeth
