FGF23 and X-linked hypophosphatemia: Enlargement of pulp chambers was also restored in FGF23-mAb treated Hyp mice when compared with vehicle-treated Hyp mice (P = 0.004 2, P = 0.000 2, respectively) (Fig. 3a–e), which is consistent with the amelioration of pulp chamber size in the XLH patient treated with burosumab.