MIH: How BioMin is helping the fightback!

Molar incisor hypomineralisation (MIH) is a developmental dental condition which affects the enamel of permanent teeth, becoming apparent just as children’s adult teeth are coming through. According to the British Society of Paediatric Dentistry, the affected teeth are likely to be molars, incisors and sometimes the adult canines can be affected too.

MIH is most likely to be seen on the first four adult molars to come through, one in each back corner of the child’s mouth. Teeth affected by MIH typically have poor-quality enamel with a white, yellow or brown discoloration. This faulty enamel is more vulnerable to crumbling and decay.

The severity of these enamel defects can vary widely. In its mildest form, it is possible for a child to have MIH and for parents to be unaware of the condition, with only a dentist being able to identify the telltale signs. In more severe cases, the back teeth can actually break down, causing extreme sensitivity, decay and even the loss of the teeth.

The problem is on the rise; it is thought to affect about 15% of Caucasian children, and dentists have seen the cases going up in recent years. ‘In our clinic at the Dental Hospital we see two or three patients every session,’ explained Dr Greig Taylor, an expert in MIH at Newcastle University. The research suggests that about one in seven UK children are affected, in line with other European countries.

‘This may be because advances in dental hygiene and water fluoridation have generally improved caries rates, so we are now seeing more cases of MIH,’ he said. While most mild to moderate cases of MIH are usually managed by general dentists, the more complex ones come into specialist clinics like his which can offer specialist treatment and more advanced restorative options.

The problem is first seen when the adult teeth start to come through, between the ages of around 7 and 11 years, and the main symptoms include:

• Hypersensitivity
• Difficulty gaining adequate anaesthesia
• Atypical carious lesions
• Post-eruptive breakdown – crumbling of posterior teeth
• Reduction in resin bond strength
• Aesthetic concerns – brown or yellow discoloration
• Reduction in quality of life.

‘Younger children aged around 8-10 usually come in due to the back teeth crumbling, because of the hypomineralised enamel,’ explained Dr Taylor. ‘This leads to pain and sensitivity, especially with cold foods – ice cream or cold drinks. By the time they reach 12 or 13 they are becoming more aware of the look of their teeth and may become concerned about the discoloration.’ The crumbling usually starts to tail off after about the age of 9 or 10, and the discoloration of front teeth can improve slightly over time.

It’s still not clear what causes MIH, but it is thought that it might occur following a challenging birth, or infection or trauma in the first year of life, when those teeth are being formed. The commonest of these are: infections such as measles, urinary tract infection, otitis media, gastric disorders, bronchitis, kidney diseases, pneumonia, asthma, fever, or antibiotic use. Experts now think there may also be an epigenetic component to this.

Dr Esther Shin, a paediatric dentist at the Toothbeary specialist children’s practice in London, says she’s seeing more cases of MIH in her practice too.

One of the difficulties with MIH, however, is that the sensitivity can make brushing painful, which exacerbates the risk of decay. Fortunately, she said, the problem usually eases as the child gets older, and cleaning becomes easier as the bite becomes established.

The management of MIH depends on the severity of the condition, but protecting the enamel and reducing the hypersensitivity is the first line. ‘It’s important to get something on the teeth as soon as possible,’ said Dr Taylor.

Mildly affected teeth can be coated with a fissure sealant, while if the problem is more severe a white restoration or metal crown may be needed or, in extreme cases, extraction of back teeth.

Bleaching of the discoloured teeth is not currently permitted in the UK for children. ‘There are many factors involved and the public are generally keen to avoid extractions and save teeth.

We prefer not to extract teeth too early, so we frequently use a sensitivity paste and bide our time,’ he said. ‘If we can delay treatment to the front teeth, it can make the cosmetic judgement better. We try to be minimally invasive.’ Sometimes, however, extraction of crumbling back teeth can be unavoidable, especially if the child’s quality of life is being affected.

Ferranti Wong, Professor of Paediatric Dentistry at Queen Mary University London and another expert in MIH, agrees, and considers the management of sensitivity essential. Many of his young patients are referred to him by their dentists who have recommended mainstream sensitivity brands without success.

‘We take a conservative approach,’ he explained. ‘We have found that BioMin^® F is very effective in calming down the sensitivity.’ It is believed that the defects in the enamel mineral create a channel through which the dentine is exposed to external stimuli causing the sensitivity. ‘We want to strengthen the enamel, by replenishing the mineral,’ explained Prof Wong. ‘BioMin^® F creates an environment where calcium, phosphate and fluoride are released slowly and continuously over several hours, working with the saliva to form fluorapatite.’ This strengthens the tooth enamel and blocks the open tubules to reduce sensitivity.

Dr Greig Taylor added: ‘It would be fantastic if you could slow down or in some cases prevent breakdown of the enamel. The benefit of a remineralising agent is that it improves the sensitivity as well as making the teeth less susceptible to breakdown. An agent that could remineralise, reduce sensitivity and also improve the aesthetics would be a win-win.’ He also believes that it’s important for the decision on treatment, including whether or not to extract, should be a shared decision with the child, and that if a dentist is in doubt as to the course of action, the case should be referred to a specialist. ‘People are listening to younger children now, and the younger ones are reporting their pain,’ commented Professor Wong.

In the longer term, new composite restorative materials are under development that not only fill the cavity but actively work to remineralise the area around it. BioMin Technologies is working on ways to use its unique bioactive glass technology in this way, and Professor Wong is excited by the possibilities.

In the meantime, BioMin^® F toothpaste is giving practitioners another string to their bow when tackling the problem of sensitivity in MIH. Nathan Smith, a clinician in East Molesey, Surrey, has been recommending BioMin^® to his MIH patients for the last few years. ‘I have seen tremendous results in the reduction of sensitivity,’ he said.