Prevalence and Presentation Patterns of Enamel Hypomineralisation among Paediatric Hospital Dental Patients in Toronto, Canada

Purpose: To determine the prevalence and presentation patterns of molar incisor hypomineralisation (MIH) and hypomineralised second primary molars (HSPM) in the Division of Paediatric Dentistry at The Hospital for Sick Children in Toronto, Canada. Methods: A cross-sectional study of 429 participants was performed by 9 calibrated examiners. The study used the European Academy of Paediatric Dentists criteria in diagnosing and documenting MIH/HSPM based on clinical presentation, size, and location of defects. Results: MIH prevalence was 12.4% (n=29) and 5.2% (n=19) for HSPM. Demarcated white opacities were the most common clinical finding of MIH (60%) and HSPM (67%). In both MIH and HSPM, single surface hypomineralised lesions were significantly more common than multi-surface lesions (pM.Sc