What is Molar Incisor Hypomineralisation (MIH)?

More and more children are appearing in the Murcian dental clinic Vélez and Lozano with this syndrome and parents concerned about the aesthetics and integrity of their children's teeth. This happens not only in Spain but all over the world, so it is important to know what it is and what to do about it.


The Molar Incisor Hypomineralisation, MIH is a change in tooth enamel that affects one or more of the first permanent molars and incisors, although it can only be seen when the tooth has erupted.

Occasionally, baby teeth are affected, but this does not mean that the permanent teeth will also be affected.


 MIH is characterised by the presence of spots opaque white, yellow and brown brown, matt, asymmetrical, well-defined, with high porosity, asymmetrical, well-defined and highly porous. But the problem is not only the stains, but also that the tooth underneath is very weak. is very weakened.


 The enamel, the outer layer of the tooth, is a highly mineralised and resistant is a highly mineralised and resistant layer that protects teeth from decay, knocks and external and external stimuli. When it weakens, the teeth become unprotected. unprotected, and this has some consequences for the child:

  • Hypersensitivity, which prevents children from brushing and the local anaesthesia does not have the desired effect. desired effect.
  • Poor aesthetics in the anterior teeth.
  •  Appearance of rapidly advancing carieswith great destruction of the crown.
  •  As the enamel disintegrates and the caries bacteria advance so quickly, they will quickly reach the pulp (the nerve) and will cause pain e infectionsometimes resulting in the loss of the tooth.
  •  Retreatments, as the fillings do not adhere well to quality enamel, so they fail and have to be repeated more often than usual. and have to be repeated more often than usual.


During the formation of a tooth with MIH, something goes wrong and the cells that form the enamel leave defects on its surface. The MIH has been linked to some diseases such as asthma, otitis, pneumonia or chicken pox.and by taking antibiotics or anti-inflammatory drugs... but still no clear and direct cause has been determined. We do know that this process takes place at the end of pregnancy and during the first two years of a child's life, when teeth are formed.

MIH Slight

Not all MIH are the same. There is cases mildwhere the stains are white and well-defined and the enamel underneath is less strong than normal, but strong enough so that there is no decay or sensitivity.

Moderate MIH

In the cases moderates yellowish spots can be seen on one or two surfaces of the tooth, without fracturing the tooth enamel and are no more sensitive than normal.

Severe MIH

The cases severeOn the other hand, they present darker stains, with broken enamel, increased sensitivity, and very defective old fillings due to what we mentioned previously.

A lot can be done to minimise the damage of MIH syndrome, and we will look at this in detail very soon, but if one of your children has this type of spotting, I advise you to maintain very good hygiene, and to see a doctor as soon as possible. paediatric dentist to assess the case.