PAEDS MIH Flashcards
What are the stages of enamel formation?
- Matrix formation
- Initiation mineralisation
- Maturation
What happens during enamel matrix formation?
Enamel matrix is formed by ameloblasts
What happens during enamel initial mineralisation?
Large amounts of ca2+ are deposited and mineralised during initial mineralisation. Stage 2 cannot occur without the formation of matrix
What happens during enamel maturation?
10% of ca2+ is deposited and water and protein content are removed leading to maturation of enamel.
What is DDE
Developmental defects of enamel
Types of DDE
- Hypoplasia - quantitative defect
- Hypomineralistion - qualitative defect
What stage of enamel development is affected when hypoplasia occurs?
Stage 1 - matrix formation
What stage of enamel formation is affected in hypomineralisation?
Stage 2 or 3 - calcification
DDE Aetiology
SYSTEMIC:
Ph change
Temperature change
Nutritional deficiencies
Calcium deficiency
Pollutants
Genetics
Childhood diseases - especially those that cause fevers
Respiratory disease
Brain hypoxia
Antibiotics - amoxicillin
LOCAL:
Trauma
Abscess formation over deciduous tooth
Define MIH
Hypomineralisation of systemic origin of 1-4 permanent first molars, frequently associated with incisors.
Diagnostic criteria for MIH
Demarcated opacity
Post eruptive enamel breakdown
Atypical restorations
What is the prevalence of DDE
20% is otherwise healthy children, 80% in children with genetic or medical conditions
Prevalence of MIH
Prevalence is varied, 20% generally.
Signs of hypomineralised teeth and tooth structure changes?
Increased porosity
Decreased hardness
Decreased mineral content
Defective microstructure
Increased carbonate content
Poor bonding properties
Associated pupal changes
Extremely sensitivity
Ineffective LA
Increased caries risk
Wear, erosion
PEB
Poor restorative results
Defective molar teeth are more susceptible to…
PEB from occlusal forces and caries
Why wont restorations succeed in MIH
Prismatic morphology in porous enamel is altered, so there is poor bonding
If enamel is more carbonated, waht does that mean?
Enamel is more soluble
What are the treatment options for MIH
Microabrasion
CR Veneers/Crowns
Resin infiltration
Porcelain veneers
Etch bleach seal technique
External bleaching
Explain microbabrasion
Using 18 or 37% phosphoric acid on enamel and followed by CPP-ACP for remineralisation. Treats whitish, creamy, shallow opacities, not usually effective for MIH, as defects usually extend thru full enamel thickness.
Explain resin infiltration
Resin infiltration is done with 15-20% HCl acid etchant, ethanol and triethylene glycol dimethacrylate monomer, to improve the translucency of enamel.
Explain etch seal technique
To remove yellow brown stains, tooth is bleached with 5% NaOCl for up to 20mins and then 37% phosphoric acid is applied for clear resin sealant. Effectiveness = ?
