Molar Incisor Hypomineralization or MIH is a developmental condition seen in children presenting as enamel defects in the permanent incisors and the first permanent molars with eruption of these teeth. It is reported in – ncbi.nlm.nih.gov by Nishita Garg. It is an irreversible condition as the enamel once deformed cannot be healed and Early diagnosis is of utmost importance as rapid breakdown of tooth structure may occur.
The main problem in MIH is Hypomineralization during enamel mineralization stage or maturation stage. This process is important, as once enamel is formed it is not remodeled for the rest of the life. Hypomineralization leads to tissue translucency where a yellowish or brownish or white area can be seen with no variation in its thickness.
Other conditions which are similar to MIH are Enamel Hypoplasia, Enamel Hypomineralization, Amelogenesis Imperfecta and Fluorosis. MIH is also described as idiopathic enamel hypomineralization in FPM, nonfluoride hypomineralization in FPM and cheese molars which have been reported in European Academy of Pediatric Dentistry Congress in 2000.
Clinical Features of Molar Incisor Hypomineralization:
- Rapid caries progression (because of lack of brushing due to hypersentivity)
- Large demarcated opacities, whitish-cream or yellow brown in color
- May or may not be associated with post eruption enamel breakdown
- Difficult to anesthetize (due to subclinical pulpal inflammation due to porosity of enamel)
- Intact enamel surface is hard, smooth and often hypermineralized
Etiology of MIH:
The exact Etiology of the condition is not completely clear, there are many putative etiological factors like prenatal, perinatal and postnatal illness, low birth weight antibiotic consumption and toxins from breastfeeding etc which can lead to MIH. Hypoxia due to lack of oxygen during delivery or after delivery is also thought of to be an etiological factor for enamel hypomineralization.
Treatment of Molar Incisor Hypomineralization:
There can be many hindrances in the treatment plan due to the symptoms seen in MIH like increased sensitivity making it difficult to manage the child, decreased cooperation from the child due to difficulty in anesthetizing the tooth, the restorations break down repeatedly due to hypomineralized enamel.
The treatment modalities are divided into four types – Preventive, Direct restoration, Full coverage restoration and Extraction and orthodontic consideration.
Preventive: Topical Fluoride application, Desensitizing toothpaste, GIC sealants to provide caries protection.
Direct Restoration: GIC restoration (Conventional GIC, resin modified GIC), Composite resin restoration (polyacid modified resin composites) but restricted to non stress bearing areas.
Full coverage restoration: In case of moderate to severe deformity it is better to provide full coverage restoration like Stainless Steel Crown to prevent further tooth deterioration, control sensitivity etc. Even Indirect adhesive or cast crown and onlays are an option.
Extraction: It can be considered as option if the tooth is un-restorable with severe hypomineralization, large multi surface lesions, apical pathosis and in cases of orthodontic space requirements with health premolars and also in case of financial considerations precluding other forms of treatment. It is important to note that the ideal age for extracting the FPM affected by MIH is around 8.5-9 years for orthodontic treatment.