Hypomineralised second primary molars may be indicative of future molar incisor hypomineralisation

##Background The term hypomineralised second primary molars (HSPM) describes a prevalent qualitative developmental defect of enamel. Children with HSPM are at a high risk of caries, and are reportedly five times more likely to develop molar incisor hypomineralisation (MIH). ##Aetiology There is an overlap in the development of the second primary molar and the first permanent molar. It is likely that MIH and HSPM have some shared aetiological factors, but in the case of HSPM the insult likely occurred earlier. ##Diagnosis HSPM can be identified as soon as the second primary molar erupts. It has a distinct clinical presentation and many clinical similarities with MIH. HSPM should be differentiated from typical early childhood caries. ##Conclusion Early dental visits for all children would allow early diagnosis of HSPM, which is essential to prevent future problems. Dental teams who work with children should be familiar with the signs of HSPM and use high caries risk preventive strategies, as well as increased vigilance during eruption of the first permanent molars.