Transcript MIH Molar Incisor Hypomineralization

MIH
Molar Incisor Hypomineralization
Dr S E Jabbarifar 2010
Lecturer in Paediatric Dentistry (Paediatric Dentistry)
MIH
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Introduction
Clinical Presentation
Prevalence
Aetiology
Treatment
MIH
 Molar-Incisor hypomineralization is
defined as a hypomineralization of
systemic origin that affects one to all of
the first permanent molars and is often
associated with affected permanent
incisors (Weerheijm et al., 2001)
MIH
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MIH molars can create serious problems
for the dentist as well as for the child
affected
MIH
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Dentists
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rapid caries development
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inability to anaesthetize
the MIH molar
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unpredictable behaviour
of apparently intact
opacities
restoration difficulties
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Child
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experience pain and
sensitivity (even when
the enamel is intact)
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Pain during brushing
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appearance of their
incisor teeth
Clinical Features
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Primary teeth are not affected
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one, two, three or four permanent first molars
affected
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white/yellow/brown opacities
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well demarcated compared to normal enamel
Clinical Features
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usually presents on the buccal or occlusal
surfaces of the molars and incisors
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asymmetrical defects
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the risk of defects to the incisors appears to
increase when more first permanent molars
have been affected
Clinical Features
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the affected molars are sensitive to cold and
appear to be more difficult to anaesthetise
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the lesions on the incisors are usually not as
extensive as those in the molars and present
mainly a cosmetic problem
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the remaining permanent dentition is usually not
affected
Diagnosis
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It is important to diagnose MIH,
delineating it from other developmental
disturbances of enamel
Diagnosis
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Diagnostic criteria to establish the presence of
MIH include:
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the presence of a demarcated opacity (defect altering
the translucency of the enamel)
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posteruptive enamel breakdown (loss of surface
enamel after tooth eruption, usually associated with a
pre-existing opacity)
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atypical restorations (frequently extend to the buccal
or palatal smooth surfaces reflecting the distribution of
hypoplastic enamel)
Diagnosis
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Mild MIH
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Demarcated opacities are in nonstress-bearing areas
of the molar
No enamel loss from fracturing is present in opaque
areas
There is no history of dental hypersensitivity
There are no caries associated with the affected
enamel
Incisor involvement is usually mild if present
Diagnosis
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Moderate MIH
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Atypical restorations can be present
Demarcated opacities are present on occlusal/incisal
third of teeth without posteruptive enamel breakdown
Posteruptive enamel breakdown/caries are limited to 1
or 2 surfaces without cuspal involvement
Dental sensitivity is generally reported as normal
Diagnosis
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Severe MIH
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Posteruptive enamel breakdown is present
There is a history of dental sensitivity
Caries is associated with the affected enamel
Crown destruction can advance to pulpal involvement
Defective atypical restoration
Aesthetic concerns are expressed by the patient or
parent
Differential diagnosis
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MIH can sometimes be confused with
fluorosis or amelogenesis imperfecta
Differential diagnosis
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It can be differentiated from fluorosis as its
opacities are demarcated, unlike the diffuse
opacities that are typical of fluorosis
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fluorosis is caries resistant and MIH is caries
prone
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fluorosis can be related to a period in which the
fluoride intake was too high
Differential diagnosis
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Choosing between amelogenesis imperfecta (AI) and MIH:
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only in very severe MIH cases, the molars are equally
affected and mimic the appearance of AI
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In MIH, the appearance of the defects will be more
asymmetrical
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In AI, the molars may also appear taurodont on radiograph
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There is often a family history
Prevalence
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The prevalence figures range from 3.6–25%
and seem to differ between countries
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The number of hypomineralized first permanent
molars in an individual can vary from one to
four
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The frequency of MIH molars was not evenly
divided among children
Aetiology
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Amelogenesis is a highly regulated process
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The asymmetrical occurrence of MIH suggests
that the ameloblasts are affected at a very
specific stage in their development
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Children with poor health during the first 3 years
of life are more likely to be at increased risk for
MIH
Aetiology
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Ameloblast cells are
irreversibly damaged
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Clinically these appear
as yellow or
yellow/brown
opacities
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These opacities are
more porous
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Ameloblasts have the
potential to recover
after the disturbance
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These defects appear
creamy yellow or
whitish cream
demarcated opacities
Aetiology
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Various causes of MIH have been implicated:
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Environmental conditions
Respiratory tract infections
Perinatal complications
Dioxins
Oxygen starvation and low birth weight
Calcium and phosphate metabolic disorders
Childhood diseases
Antibiotics
Prolonged breast feeding
the aetiology of MIH still remains unclear
Restoration
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Children with MIH may have extensive treatment needs
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By the age of nine, children with MIH were treated ten
times as often as children without such molars
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MIH children display more dental fear and anxiety
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Children with MIH exhibited greater DMFS and dmfs
Restoration
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MIH molars are fragile, and caries may develop
easily in these molars
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This is aggravated because children tend to
avoid the sensitive molars when brushing
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In order to minimize the loss of enamel and any
damage due to caries, both preventive and
interceptive treatment is required
Restoration
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Besides normal brushing and education, prevention also
includes fluoride varnish application and application of
glass ionomer sealants
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Sometimes the sensitivity of the teeth is decreased by
these applications
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In some cases of hypersensitivity the use of casein
phosphopetide-amorphous calcium phosphate (CC-ACP)
(Tooth Mousse) products have been advised as they
remineralize and desensitize the tooth
Extraction
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Extraction combined with orthodontic
treatment, should be considered as an
alternative treatment, especially if the
molars have a poor longterm prospect.
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The optimal time for extraction is
indicated by the calcification of the
bifurcation of the roots of the lower
second permanent molar
Short-Term Treatment
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The immediate treatment planning needs of young
children with MIH must reflect:
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Behavioural
Preventive
growth and development
restorative requirements
The objective is to:
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maintain function
preserve tooth structure
plan for any required orthodontic care
Partially Erupted Molars
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Prone to caries development and highly sensitive
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Applying desensitizing agent in combination with fluoride
varnish applications could be of some help in decreasing
sensitivity
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GI to cover the affected surfaces of a partially erupted
molar can act as an interim method of:
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decreasing sensitivity
reducing caries susceptibility
preserving tooth structure
Mild MIH: Short-Term
Treatment
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Prevention and maintaining the dentition
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Teeth should be carefully monitored
applying fluoride varnish and placing sealants on the occlusal
surfaces of molars
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where the enamel is intact and the patient does not report any
sensitivity, sealants are the current treatment of choice
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60-second pretreatment with 5% sodium hypochlorite (NaOCl)
to remove intrinsic enamel proteins may be beneficial
Moderate MIH: ShortTerm Treatment
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preventive measures previously outlined
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intervention may be required
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Anterior teeth with isolated demarcated opacities that are of
aesthetic concern can be treated with NaOCl or other bleaching
techniques, microabrasion, or resin restorations
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Yellow or yellow/brown spots in incisors or molars can lighten
and become less noticeable with bleaching, but whitish opacities
may become more prominent after applying the bleach
Moderate MIH: ShortTerm Treatment
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For posterior teeth with enamel loss or decay limited to 1
or 2 surfaces that does not involve cuspal tooth structure,
resin is the material of choice if the tooth can be
adequately isolated
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The outline of the restoration should be made in nonhypomineralized enamel, but it can be very difficult to find
out where sound enamel begins, resulting in repeated
restorations due to disintegration of adjacent enamel or
opacities on other spots.
Moderate MIH: ShortTerm Treatment
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Two approaches have been described in determining the
location of the cavity margin but neither is ideal
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Fall the visibly defective enamel is removed
Only the very porous enamel is removed until good
resistance is felt between the bur and the sound enamel
Existing, intact restorations on molars should be carefully
monitored
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Available adhesive dental materials
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GI
RMGI
Compomer
RBC
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Glass ionomers and resin-modified glass ionomers have
poor wear resistance and are not recommended for
placement in stress-bearing areas
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The enamel-adhesive interface
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Porous
Cracks
Decreased bond strength
Cohesive failure
Severe MIH: Short-Term
Treatment
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Treatment of children with severe MIH presents a
tremendous challenge
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Early intervention is necessary to prevent PEB
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To minimize discomfort and decrease the likelihood of
behaviour management problems, profound local
analgesia is necessary
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Some patients may benefit from the use of nitrous oxide
sedation in conjunction with local anaesthesia
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Once the molar has erupted, preformed
stainless-steel crowns are the treatment of
choice for severely hypoplastic molars
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Stainless-steel crowns protect the tooth against
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masticatory forces
protect enamel from acid attack
decrease sensitivity
increase the child’s OH compliance
Long-Term Treatment
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Once children have a mature dentition and a
more stable gingival to clinical crown height,
full-coverage cast restorations should be
considered to replace the interim stainless-steel
crowns on molars
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Anterior teeth can be managed with veneers or
crowns should they be indicated for severe
cases of enamel defects, and where aesthetic
concerns continue to be an issue
Summary
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Early Diagnosis
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High risk prevention protocol
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Make a decision regarding prognosis of the
molars
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Extract if prognosis is poor or if behaviour
management will be an issue
Summary
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Replace missing tooth structure
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Use best available restorative material
SSC ideal
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Regular recall
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Delay aesthetic treatment of the incisors until
the child requests treatment
Thank You