Introduction: Familial hypophosphatemic rickets, the most common cause of inherited rickets, is in most cases transmitted as an X-linked dominant trait resulting from a mutation of the phosphate-regulating gene with homologies to endopeptidases on the X chromosome gene. This condition impairs bone, cement and dentin mineralization, resulting in skeletal and oral manifestations. Patients present spontaneous tooth abscesses that occur without any history of trauma or dental decay. Methods: Two XLH patients were referred to the endodontic department of Charles Foix Hospital. They reported history of multiple dental abscesses. The clinical and radiographic examination showed periapical lesions of central left mandibular incisor and first and second maxillary left molars. Furthermore, the radiographic examination showed enlarged pulp chambers, thin enamel and dentin. Conservative endodontic treatment was performed in the necrotic teeth. Results: The clinical and radiographic follow-up showed a bone healing in process in these two cases.
