Generalized Developmental Enamel Hypoplasia of the Permanent Dentition Associated with Early Childhood Vitamin D Deficiency Rickets: A Case Report

Background: Vitamin D deficiency rickets is a metabolic bone disorder caused by impaired calcium and phosphate homeostasis resulting from insufficient vitamin D. In children, severe vitamin D deficiency can disturb the mineralization of growing bones and teeth. Although the skeletal manifestations are well recognized, reports describing generalized developmental enamel defects affecting nearly all permanent teeth remain limited. Methods: A 6-year-9-month-old Japanese boy with a history of vitamin D deficiency rickets diagnosed at 2 years 5 months of age was referred to our department for evaluation of generalized discoloration and morphological abnormalities affecting multiple permanent teeth. Clinical, radiographic, and medical findings were reviewed. Results: Laboratory examination at diagnosis revealed severe vitamin D deficiency with elevated intact parathyroid hormone levels. Possible contributing factors included exclusive breastfeeding, delayed weaning, avoidance of fish and dairy products, and limited outdoor activity. Following oral alfacalcidol supplementation, skeletal and biochemical findings gradually normalized. However, clinical examination revealed generalized enamel hypoplasia affecting the permanent incisors and first molars, characterized by yellow-brown discoloration, rough enamel surfaces, morphological irregularities, and attrition, whereas the primary dentition showed no obvious abnormalities. Panoramic radiography demonstrated generalized crown malformation involving both erupted and unerupted permanent teeth, particularly the permanent incisors, first molars, and canines, while premolars and second molars were relatively unaffected. Based on the developmental timing of the affected teeth and the patient’s medical history, the enamel defects were considered to be associated with systemic mineralization disturbance during early childhood. Restorative treatment, including composite resin restorations and stainless steel crowns, was performed to improve aesthetics and occlusal function. Preventive surgical exposure followed by composite resin restoration was also performed for the permanent canines at the onset of eruption. Conclusions: Severe vitamin D deficiency during critical stages of tooth development may be associated with irreversible developmental enamel defects in the permanent dentition, even after apparent systemic recovery from rickets. Early dental assessment, long-term dental follow-up, and multidisciplinary management should be considered in children with a history of nutritional rickets.