Cheese Molars in Kids

Molar Incisor Hypomineralisation

“My child brushes his/her teeth twice every day. We don’t have any sweets, soft drinks, or fruit juice at home yet it seems my child is always at the dentist with a tooth problem.” Is this familiar to you? Have you ever thought about why this could happen?

Defects of the enamel of the tooth can happen at the time of tooth development. These defects can affect both the quality and quantity of the enamel. If the quality of the tooth is compromised during enamel formation it is referred to hypomineralization.

In 2001, Weerheijm described a condition called Molar Incisor Hypomineralization (MIH)

MIH: Hypomineralization of 1 or more of the permanent first molars with a systemic origin and frequently involving the incisors.

The global prevalence of MIH has been reported to be 4.4% by  Zhao in 2018. In an Australian study in Sydney Balmer reported the prevalence to be roughly 40%.


Molar Incisor Hypomineralisation

You can see in the photo above the first permanent molar is just erupting in a 6-year-old child. The dark discoloration and opacities on the tooth is a sign of defects of the enamel.

A systematic review by Americano et al. in 2016 reported children with MIH are 4 times more likely to experience caries in their teeth. It is very common for children with good oral hygiene and diet to experience caries and tooth pain due to this condition.

In a study by Fagrell in 2008, it was reported that in the absence of a carious lesion on the surface of the tooth the underlying structure can be invaded by bacteria.

These teeth are usually very sensitive to cold and other thermal stimuli. This has been explained by Helen Rodd in 2008 due to increased pulpall innervation density and thermal receptors at the pulp horns and subodontoblastic layer.

MIH Molars

Hypomineralised molars have more protein content in the enamel causing reduced hardness. The darker the color of the opacities on the tooth the more protein content and the weaker the teeth will be. These molars may not be able to withstand the forces of mastication and they will break down soon after they have erupted.

Innervation to the hypominralized teeth may also be abnormal causing difficulty in achieving anesthesia for dental treatments.

Studies have reported children with MIH will undergo 10.5 times more dental treatment than children without MIH.

If the incisors are affected, aesthetics can be a concern. There are different options to improve the aesthetic of these teeth.

Hypomineralization can also affect primary molars. This condition was described by Elfrink in 2008 and named Hypomineralization of Second Primary Molar (HSPM).  Children with HSPM are 4.4 times more likely to have MIH.

enamel defects in baby teeth

This photo demonstrated a dentition that has no caries, but the second primary molar has been extracted before the age of 6. This is due to the defects described earlier. On the other side, the defect can be seen in a much milder form as a white opacity.

What causes MIH and HSPM

The exact etiology remains unclear, but many different possible causes have been mentioned in the literature including:

  • Early childhood disease
  • Antibiotic use in early childhood
  • Premature birth, low birth weight
  • Vitamin D deficiency
  • Genetics
  • Environment factors, dioxin
  • Prolonged breastfeeding
  • Respiratory infections
  • Prenatal complications

How Can MIH be Managed in Children?

This condition needs to be diagnosed very early on. Regular check-ups from a young age and establishing a dental home for your child can help to recognize these defects very early.

Preventive measures are very important. Bushing x2 daily with fluoridated toothpaste and a healthy diet with minimal sugar intake can help to prevent the superimposition of any other dental issues.

Professional fluoride treatment every 6 months can help reduce the risk of caries.

Sensitivity can be managed by fluoride treatment, use of tooth mousse (CPP-ACP). A study by Gamboa in 2018 has investigated the effect on silver diamine fluoride 38% in reducing sensitivity in MIH and has found promising results.

Fissure sealants can help protect the deep grooves and reduce the risk of caries and breakdown.

MIH in Front Teeth

MIH in anterior teeth can cause great aesthetic concerns. Treatments available are dependent on the severity of the defect.

In milder cases bleaching, microabrasion and resin infiltration may be helpful. In more severe cases composite dental veneers, porcelain veneers, or full coverage with a dental crown may be advised.

There are different treatment options are available for posterior teeth.

In mildly affected teeth treatment may include fissure sealants, composite fillings, fillings with glass ionomer cement, or resin-modified glass ionomer cement.

It has been reported by Kramer in 2018, composite bonding to enamel surface with defects has limitations. Therefore, fillings may fail sooner or more regularly in teeth with MIH.

According to Pure Dentistry Dentists in Brisbane More severe defects can be protected with stainless steel crowns or other full-coverage options.

Sometimes the breakdown of the tooth is very severe and the tooth is not restorable. In this case, the tooth may need to be extracted. For extraction of the first permanent molar, some studies have reported an optimal time but more recent studies by Wu in 2017 have not been able to prove there is an optimal time for extraction of the first permanent molar. Orthodontic consult is desirable before the extraction of the first permanent molar.

enamel defects in baby teeth

If the primary molars are extracted at a young age a dental space maintainer may be indicated.