BACKGROUND: Systemic mastocytosis (mast-cell proliferation in various organs, including the skeleton) is a rare disease. Reports on mastocytosis that affects facial bones are few. The bone lesions may be osteolytic or sclerotic. PURPOSE: To describe (for the first time) bone grafting followed by dental implant treatment yielding a good result in a patient with systemic mastocytosis. MATERIALS AND METHODS: A bone graft was performed on a 60-year-old woman with systemic mastocytosis. Dental implant treatment was performed 13 weeks after sclerotic bone of the iliac crest was grafted to the maxillary sinus bilaterally. A microimplant was installed simultaneously with the dental implants and was removed 6 months later for histomorphometric evaluation. Bone biopsy specimens from the donor site of the sclerotic iliac crest and later from the remodeled maxillary bone graft were histologically analyzed. A clinical examination of the patient with regard to her mastocytosis was performed by a dermatologist. The patient was followed up after 3 years. RESULTS: Bone grafting and dental implant treatment were successful, and the patient's clinical and radiologic situation was stable after 3 years. Histologic examination of the bone grafted from the iliac crest showed sclerotic lesions in the bone and a dense infiltration of mast cells. The bone graft seemed to remodel initially in a normal way in the maxillary sinus. However, computed tomography 3 years later showed regions of sclerosis in the remodeled maxillary bone. These lesions now had a pattern similar to the adjacent facial bone. Both the microimplant and the dental implants integrated well. Bone-implant contact measured on the microimplants was 20% higher in this actual case, compared to that of patients previously treated and grafted with the same technique. CONCLUSIONS: There are many clinical implications to be considered when treating this group of patients. Bone grafting, remodeling of the bone, and dental implant installation were successful in this patient with systemic mastocytosis and signs of osteosclerosis. Installation of microimplants in patients with pathologic bone conditions may allow successful dental implant treatment.