Amelogenesis Imperfecta

Amelogenesis imperfecta is a group of inherited disorders affecting the structure and clinical appearance of enamel in both primary and permanent dentitions. Prevalence ranges from 1:700 to 1:14,000 depending on population. Genetic causes include mutations in AMELX (X-linked), ENAM, MMP20, KLK4, FAM83H, WDR72 and ITGB6. Classification by Witkop based on enamel defect type and inheritance pattern: hypoplastic AI (defective enamel matrix formation, thin or pitted enamel), hypomaturation AI (abnormal enamel maturation, mottled creamy white-brown), hypocalcified AI (severely soft enamel that wears rapidly), and mixed forms.

Clinical features include discoloration ranging from yellow-brown to brown-gray, hypersensitivity to thermal stimuli, susceptibility to caries and attrition, anterior open bite (in 60% of cases), gingival inflammation due to plaque retention, and psychosocial impact in adolescence. Both primary and permanent dentitions are affected, sometimes asymmetrically. Hypocalcified type shows the most rapid wear and aesthetic problems.

Diagnosis combines clinical examination, family history, radiographs (showing reduced enamel-dentin contrast in hypocalcified type), and genetic testing. Management is multidisciplinary and lifelong, including preventive measures (fluoride varnish, sealants, dietary counseling), treatment of hypersensitivity (desensitizing toothpaste, MI Paste), restorative dentistry (composites, full-coverage crowns, onlays, veneers), orthodontic correction of malocclusion (open bite), and esthetic rehabilitation. Treatment in childhood may use stainless-steel crowns; permanent teeth often require zirconia or PFM crowns. Genetic counseling is essential.