The term Molar incisor hypo mineralization (MIH) was first introduced in 2001 as a developmental disorder of enamel characterized by hypo mineralization -of systemic origin - affecting the enamel of first permanent molars (PFM) ,frequently associated with affected permanent incisors.~The prevalence of MIH varies widely, ranging from 2.4 % to 40.2% in different populations. This wide variation may be due to differences in diagnostic criteria and methodologies used by the authors. Concerning the etiology of MIH it is mostly related to pre natal, perinatal, and post natal illness.~Asthma and asthmatic drugs have been proposed to be one of the etiological factors of MIH,Internationally, the mean prevalence of pediatric asthma is 10%.
The aim of this study is to assess the prevalence of molar incisor hypo mineralization among children who have been treated with asthmatic drugs during the first three years of life.