This document discusses amelogenesis imperfecta, a group of conditions that cause developmental abnormalities in dental enamel. It begins by outlining the objectives of describing various tooth structure disorders, classifying amelogenesis imperfecta and enamel hypoplasia, and their etiopathogenesis and clinical manifestations. It then covers the classification of amelogenesis imperfecta, describing types such as hypoplastic, hypocalcified and hypomaturation. Environmental enamel hypoplasia is also discussed, along with its clinical features and causes such as nutritional deficiencies. In summary, the document provides an overview of developmental disorders affecting tooth structure, specifically focusing on amelogenesis imperfecta and enamel hypoplasia, their classification