Molar Incisor Hypomineralisation Flashcards
What % of child referrals are due to MIH?
25%
what teeth does MIH affect
1st permanent molars
permanent incisors
What does MIH look like
- distinctive from everything else
- very well demarked
- white, yellow, brown parts
- not symmetrical
What does “hypomineralised” mean
disturbance of enamel formation (secretory phase) resulting in a reduced mineral content
(shape is fine)
What does “hypoplastic” mean
reduced bulk or thickness of enamel
True= enamel never formed Acquired = post-eruptive loss of enamel bulk
(shape is not fine)
why is it so difficult to determine aetiology
- unclear diagnostic criteria in classification
- most parents can’t remember details from 8-10 years before
- variations in quality and completeness of case records
- study populations small
when is the critical period for formation of MIH
first year of life
as enamel matrix of crown of first permanent molars is complete by 1 year
what time period do you ask about to diagnose MIH?
Ask about the 3 different time periods:
- pre-natal
- natal
- post-natal
What prenatal questions do you ask mothers
- about their general health in 3rd trimester of pregnancy e.g. pre-eclampsia, gestational diabetes
What natal questions do you ask mothers
(time around birth)
- are they full term or premature?
- any emergency procedures?
- forceps?
- baby not getting enough oxygen etc?
What postnatal questions do you ask mothers?
- could they breathe properly when they came out?
- did they spend any time in a special baby unit?
- have they had chickenpox?
- any breathing problems?
How can you spot measles in children
- fever
- rash
- Koplik’s spots (white spots in mouth)
- conjunctivitis
- cough
- coryza (runny nose)
- duration of illness =7-10days
How can you spot rubella in children
- mild fever
- maculopapular rash
- generalised lymphadenopathy
- malaise
- URTI
- duration of illness = 8-10days
How can you spot chicken pox in children
- low grade fever
- rash
- lots of spots
- duration of illness = 6-10 days
What did Fagrell et al find out about the possible aetiological factors of severe demarcated opacity (SDO)
Disturbances in nutrition in first 6 months might have an effect
What did Balmer et al find out about the relationship of MIH to socioeconomic status
association with first 4 deprivation quintiles
what is the histology like with MIH
- whole enamel layer yellow/brown (more porous)
- inner parts of enamel white/ cream
- chronologically dispersed hypomineralised demarcated opacities, higher carbon content, lower Ca,PO4
Is there underlying pulpal inflammation in MIH teeth
- more nerve innervation (senstivity, difficult to anaesthitise)
- lots more immune cell activity
- significant increase in vascularity (more inflamed)
What are the consequences for pain for MIH
- dentine hypersensitivity
- peripheral senstitisation
- central senstitisation
what is dentine hypersensitivity
porous enamel or exposed dentine facilitates fluid flow within dentine tubules to activate Adelta nerve fibres (hydrodynamic theory)
what is peripheral sensitisation
underlying pulpal inflammation leads to sensitisation of C-fibres
what is central sensitisation
from continued nociceptive input?
clinical problems for MIH
- loss of tooth substance (breakdown of enamel, tooth wear, secondary caries)
- sensitivity (don’t like brushing)
- appearance (won’t smile)
- very poorly caries resistant
treatment options for MIH
- composite/GIC restorations
- stainless steel crowns
- adhesively retained copings
- extraction (8.5-9.5yrs old)
If you’re just trying to maintain the tooth until it’s time to extract what could you use
GIC
- releases F
- deals with sensitivity
- makes tougher til time to remove
If it’s extremely sensitive what could you use
stainless steel crown
When do you decide to remove the tooth
- radiographic calcification/bifurcation of the lower 7
- good to see developing 3rd molars too
what happens if you take out the tooth too early
they will also lose perfectly good premolars to try and make space
roughly what age would you look at taking out the tooth
8.5-9.5 years (but look at dental age)
what do you consider when considering extracting HFPM’s
- age
- skeletal pattern
- future orthodontic needs
- quality of teeth e.g. caries
how do you treat affected incisors
- acid pumice microabrasion (gets rid of yellow, brown bits)
- external bleaching (13yrs before you do this, makes normal tooth colour whiter as can’t get rid of white bits)
- localised composite placement
- full composite veneers
- full porcelain veneers (not advised until after 20 as gum level changes a lot)
