Osteomalacia is a metabolic bone disease caused by vitamin D deficiency or its active metabolites. Ectodermal dysplasia is a congenital syndrome, characterized by hypotrichosis, hypohidrosis and hypodontia. Most of the the deciduous teeth form but there are few or no permanent teeth. In this case report we presented the oral rehabilitation of a 31-year-old female patient with an ectodermal dysplasia and suffering from severe osteomalacia. The patient showed severe osteomalacia, ectodermal dysplasia and primary hypogonadism and psoriasis. Due to pain on the left side of her mandible, she was referred to our clinic. The patient was taking calcium 1200mg /day and 300000 international units for every two months, vitamin D3 and vitamin B complex tablets since May 2006. After 10 months of treatment her hair and nails begun to grow and her teeth started to erupt. During the patient's clinical examination, an ill-fitting total prosthesis and inflammation due to root remnants of left first molar was found. On radiological examination, a lot of impacted shapeless ectopic teeth were seen in maxillary sinus and nasal floor regions. Canines, premolar and molar teeth were impacted in the mandible except for the first molars. The surgical extractions and the preprosthetic surgery procedures were completed. The patient showed no postoperative complications. A new prosthesis was made and her oral rehabilitation was completed. In such complicated cases a multidisciplinary approach is necessary.