An International Study of Molar Incisor Hypomineralisation and Its Association With Dental Anomalies

Background/study aim:

Molar incisor hypomineralisation (MIH) is a common disorder of tooth development. Affected teeth have weak enamel and adult molars often require extensive treatment or even extraction. A preliminary study, carried out in Sheffield Dental Hospital, discovered that 12% of MIH children also had congenitally missing adult teeth, presenting further challenges to treatment-planning. This novel finding stimulated discussion between international MIH experts; whilst some clinicians had observed this association, others had not. Therefore the primary aim of this international study is to determine the association between MIH and missing teeth in different populations. This has important clinical and biological relevance in understanding the presentation and management of MIH.

Participants/research sites:

This study will include 584 children with MIH and a comparison group of 584 children without MIH. Young dental patients, aged 7-16 years, who attend for a check-up or treatment at one of the 15 participating countries will be invited to take part. The UK sites are Sheffield, Newcastle and University College London Dental Hospitals and all children will be seen by specialists/consultants in paediatric dentistry to confirm their diagnosis of MIH. The main inclusion criteria is that children have a dental xray as part of their routine care.

Data collection:

Following a routine dental check-up we will grade the severity of the participants' MIH (if present) and record any other dental anomalies (e.g. abnormal tooth number, position or shape). We will also check the dental xray for other anomalies that cannot be seen from the clinical exam. We will analyse the prevalence of MIH and association with other dental anomalies to see if there are difference according to sex or ethnicity and compare our findings with the non-MIH group. We anticipate the study will take 18 months.