Enamel hyperplasia and hypoplasia: etiology, clinical presentation, pathogenesis, diagnosis and contemporary management

Abstract

Enamel hyperplasia and hypoplasia are developmental defects of the tooth enamel that reflect disturbances during amelogenesis. These conditions result in quantitative and qualitative abnormalities of the enamel, affecting dental hard tissues and increasing susceptibility to caries, sensitivity, and aesthetic concerns. Enamel hyperplasia is characterized by excessive enamel formation, whereas hypoplasia represents deficient enamel deposition. The multifactorial etiology encompasses genetic determinants, systemic metabolic disturbances, environmental exposures, nutritional deficiencies, and prenatal and perinatal insults. Pathogenetically, disruptions in ameloblast function during the secretory and maturation phases of enamel formation lead to these defects. Diagnosis relies on clinical examination, standardized indices, radiographic assessment, and adjunctive imaging modalities. Contemporary management integrates preventive measures, remineralization strategies, minimally invasive restorative techniques, and where necessary, prosthetic rehabilitation. Understanding the anatomical, histological, and biochemical bases of enamel development informs evidence‑based interventions aimed at preserving tooth structure and function.