Is molar incisor hypomineralisation (MIH) a new disease of the 21st century?

Introduction

The term molar incisor hypomineralisation (MIH) was used by Weerheijm, Jälevik and Alaluusa in 2001 to describe hypomineralisation of systemic origin of 1–4 permanent first molars, frequently associated with affected incisors. MIH had previously been described by various terms such as, mottling of enamel and cheese molars. Assessment of MIH between studies is confounded by different terminology, resulting in difficulty in being able to ascertain when this disorder initially presented. Asking whether MIH is a new disease of the 21st century, or whether it existed previously, may help to establish if aetiological factors are liked to contemporary lifestyle.

Materials and methods

Cochrane Library, Embase, Medline and Web of Science were the databases used to conduct an extensive literature search. Specific search terms and inclusion/exclusion criteria were used to identify relevant publications. After the screening process, 13 articles were included in this review, 5 investigated archaeological specimens, whilst the remaining 8 were clinical studies, where participants were born before the 21st century.

Results

Four common themes identified on review of the selected publications were: suggested rates of MIH between archaeological studies vastly differ, clinical studies carried out before 2001 suggest similar rates of MIH to present day, despite use of different terminology. Both archaeologic and clinical studies suggest MIH existed before the 21st century and publications using clinical assessment either focus on children or adolescents.

Conclusion

Analysis of the selected publications suggests that MIH was present before the 21st century. This is demonstrated in both clinical and archaeological studies.