Fig. 2: Oral manifestations of X-linked hypophosphataemia.

a, Oral clinical view of a 5-year-old male patient with X-linked hypophosphataemia (XLH) showing a spontaneous dental abscess on the right upper temporary central incisor. The tooth shows no discoloration or carious lesion and the child and his mother reported no history of trauma. b, Maxillo-facial cellulitis due to spontaneous necrosis of the left upper temporary canine in the same patient at the age of 7 years. c, Panoramic radiograph of the same patient at the age of 8 years showing mixed dentition with characteristic dental features of XLH, including a normal (slightly thin) enamel layer, a radiolucent dentin layer with enlarged pulp chambers and prominent pulp horns on both temporary and permanent teeth. d, Oral clinical view of a 49-year-old woman with XLH who was diagnosed at the age of 4 years. The patient was treated with oral phosphate supplements and active vitamin D during growth for 12 years before the treatment was stopped at the age of 16 years. This treatment was resumed for 4 years from the age of 40 years before being replaced with burosumab, which had been taken for 5 years. e, Panoramic radiograph of the same patient showing generalized horizontal alveolar bone loss and teeth treated endodontically owing to dental infections.