Objective: This study aimed to determine the prevalence of molar incisor hypomineralization (MIH) among a group of Egyptian children aged 8-12 years old in Giza Governorate.
Material and methods: This study was conducted in Al-Ayat in Mounira Farghally and Aldenaweya schools in Giza, Egypt. The sample size was 371 students.All the students aged 8-12 years who attended school on the day of examination were examined for the presence or absence of MIH. MIH was recorded when at least one of the first permanent molars shows any of the diagnostic criteria of MIH according to the modified index developed in line with European Academy of Paediatric Dentistry criteria.
Results: The gender distribution among the participants was 191 boys (51.5%) and 180 girls (48.5%). The mean (SD) values for age were 10.1 (±1.4) years with a minimum of 8 and a maximum of 12 years old. MIH was found in 10 children giving a prevalence of 2.7% among the examined children. The majority of the children (70%) diagnosed with MIH presented lesions in both permanent first molars and incisors with different degrees, and 30% of them presented lesions in permanent first molars only.
Conclusions: The prevalence of MIH among the study sample was 2.7%. The most prevalent defect reported in this study was demarcated opacity. The most common degree of severity of MIH in the studied population was the mild degree.