hypomineralization of systemic origin of one to four permanent first molars frequently associated with affected incisors and these molars are related to major clinical problems in severe cases

1. Molar Incisor
Hypomineralization
(MIH): Clinical
Presentation,
Aetiology and
Management
Presented By
Saeed Ahmed Saeed Bajafar
Pediatric Dentistry Master Degree Candidate
Ain Shamas University , Egypt

2. Definition :
MIH is defined as hypomineralization of systemic origin of one to four permanent first molars
frequently associated with affected incisors and these molars are related to major clinical problems in
severe cases.
❖ In the past, dentists were used to rapid caries progression in the primary as well as the permanent
dentition in high caries populations.
❖ In those days, first permanent molars became carious shortly after eruption in most cases.
In the literature :
such molars are referred to
1. non-fluoride enamel opacities
2. internal enamel hypoplasia,
3. non-endemic mottling of enamel,
4. opaque spots
5. idiopathic enamel opacities
6. enamel opacities and cheese molars
Recently :
the term Molar Incisor Hypomineralization (MIH) was suggested
MIH molars can create serious problems for the dentist as well as for the child :
Dentist The child
Unexpectedly rapid caries development
in the erupting first permanent molar
Pain
Inability to anaesthetize the MIH molar Sensitivity (even when the enamel is intact)
Unpredictable behaviour of apparently
Intact opacities
Toothache during brushing
Appearance of their incisor teeth
Prevalence :
3.6– 25% and seem to differ between countries and birth cohorts.
Clinical features :
▪ MIH is a hypomineralized defect of the first permanent molars, frequently associated with
affected incisors.
▪ The number of affected first permanent molars per patient varies from one to four
▪ expression of the defects may vary from molar to molar.
▪ Within one patient, intact opacities can be found on one molar, while in another molar large parts
of the enamel break down soon after eruption.
▪ When a severe defect is found within a subject, it is likely that the contralateral tooth is also
affected
▪ In some cases, apart from defects in the first permanent molars, opacities may be found in the
upper and sometimes the lower incisors
▪ The risk of defects to the upper incisors appears to increase when more first permanent molars
have been affected
▪ The defects of incisors are usually without loss of enamel substance.
These molars can be
extremely painful to
the children

3. Clinically, The Hypomineralized Enamel Can Be :
▪ soft, porous and look like discolored chalk or old Dutch cheese.
▪ The enamel defects can vary from white → yellow or brownish
▪ Always show a sharp demarcation between the affected and sound enamel
▪ The porous, brittle enamel can easily chip off under the masticatory forces.
▪ the loss of enamel (posteruptive enamel breakdown) can occur so rapidly after eruption
▪ After occurrence of the post-eruptive enamel breakdown, the clinical pictures can resemble
hypoplasia
▪ In hypoplasia, however, the borders to the normal enamel are smooth, whilst in posteruptive
enamel breakdown the borders to the normal enamel are irregular
▪ MIH can sometimes be confused with fluorosis or amelogenesis imperfecta.
▪ In MIH opacities are demarcated (Caries Prone)
▪ In Fluorosis diffuse opacities (Caries Resistance)
▪ The cause of fluorosis can, mostly, directly be related to the period in which the fluoride intake
was too high

4. Amelogenesis Imperfecta (AI) And MIH :
▪ Diagnosis seems a matter of definition
▪ Only in very severe MIH cases, the molars are equally affected and mimic the appearance of AI.
▪ Mostly in MIH, the appearance of the defects will be more asymmetrical in the molars as well as in
the incisors
▪ In AI, the molars may also appear taurodont on radiograph and there is often a history of family
onset.
Aetiology :
1. Environmental conditions
2. respiratory tract problems
3. perinatal complications and dioxins
4. oxygen starvation of the child
5. low birth weight
6. calcium and phosphate metabolic disorders
7. frequent childhood diseases
8. Vaccines given during early childhood
9. The use of antibiotics
Management :

5. Management of affected first permanent molars in MIH
▪ There Is No Universal Classification For MIH But The Hypomineralised Areas Have Been Classified
By Alaluusua Into
1. Mild (Color Change : White, Yellow Or Brown)
The enamel appears to be of good quality and clinical and radiographic investigations have
confirmed that the molar is caries free.
✓ the treatment of choice in ‘mildly’ affected cases → Fissure sealants
✓ Regular Check up , at least two to three times annually
✓ If Post-eruptive enamel breakdown → composite restoration can be placed
2. Moderate (Loss Of Enamel Only)
where the enamel / dentine defect is well demarcated and confined to one or two surfaces
✓ the treatment of choice in ‘mildly’ affected cases → composite restoration
✓ Regular Check up
✓ As preventive Measure → Pit and Fissure Sealnt
✓ If Post-eruptive enamel breakdown → Large composite restoration Or SSC
3. Severe (Loss Of Enamel In Association With Affected Dentine)
There is frequently cuspal, with or without pulpal involvement
✓ The treatment options are either restoration or extraction
✓ combined endodontic-orthodontic opinion is essential in such cases
✓ Taking into Consideration
1. Occlusion
2. Presence or absence of crowding
3. Overall dental development
4. Missing or malformed teeth
5. Long-term prognosis
Where restoration is the chosen option → Full Molar Coverage (Performed SSC) + GIC Contain
Fluoride is The Cement of Choice
▪ Is advisable to replace them with custom-made crowns when the child reaches their late
teenage years and gingival maturation is complete.
Extracion is the least satisfactory approach → Depending upon the number of molars extensively
affected
▪ extraction of all four molars as part of a planned orthodontic treatment plan may be the most
practical approach to care
▪ in cases where future orthodontic treatment is not an option, Jalevik and Moller have shown
that extraction of FPMs in MIH is still a good treatment alternative
Symptomatic molars may pose a difficulty in ensuring that extractions are carried out at the optimum
time. In such cases, a glass ionomer material can be used as an interim restoration to resolve
symptoms.This provides time to allow the extractions to be carried out at the projected optimal time
The endodontic option in the treatment of severely affected molars in MIH is a dilemma. The high
level of compliance, time, effort, and financial cost in undertaking the endodontic treatment, with the
subsequent need for crowning these molars in such young children, needs to be weighed against the
long-term prognosis for these heavily restored teeth.
These will determine the
decision to retain or extract the
affected molars

6. Management of hypomineralised incisors in MIH
▪ Incisor involvement is variable.
▪ Not all patients with MIH exhibit enamel opacities on their permanent incisors
▪ The Prevalence of this feature may exceed 30% in some populations
Micro-abrasion techniques acid/pumice micro-abrasion techniques tend to produce little improvement in
appearance when used alone in Case of The incisal opaque defects usually extend through the full thickness of
enamel .
Bleaching may improve yellow brown discoloration but is unlikely to improve the underlying opacity.
Direct composite veneers Unsightly opacities and defects on permanent incisors of young children can be
successfully masked using direct composite veneers.
Composite veneers can be modified or replaced with porcelain veneers later if desired, when dental and
gingival development is complete.
References :
Daly, Dympna & M Waldron, J. (2009). Molar incisor hypomineralisation: clinical management of the
young patient. Journal of the Irish Dental Association. 55. 83-6.
Pereira Alves dos Santos, Mrcia & Maia, Lucianne. (2012). Molar Incisor Hypomineralization:
Morphological, Aetiological, Epidemiological and Clinical Considerations. Contemporary Approach to
Dental Carie. 10.5772/37372.
Weerheijm, Karin. (2004). Molar Incisor Hypomineralization (MIH): Clinical Presentation, Aetiology
and Management. Dental update. 31. 9-12. 10.12968/denu.2004.31.1.9.