抄録
Focal osteoporotic bone marrow defect （FOBMD） is an area that exhibits radiolucency, corresponding to the presence of hematopoietic bone marrow tissue in the bone. We report a case of FOBMD in the mandible.
The patient was a 71-year-old man. A panoramic radiograph taken for maintenance of dental implants placed in the mandibular right molar region showed a circular translucent image with a calcification-like shadow inside at the apical area of the vital tooth. Dental cone beam CT showed mild thinning of the buccolingual cortical bone surrounding the lesion, but there was no bone expansion. The patient had no subjective symptoms. A biopsy was carried out based on a clinical diagnosis of suspected mandibular bone tumor. A bone cavity was observed at the lesion, there were bone-like hard tissue and a small amount of red muddy tissue inside the cavity. Portions of the bone-like hard tissue and muddy tissue were sampled. They were histopathologically fragmented trabecular bone and bone marrow tissue. In the bone marrow tissue, adipose tissue was mixed, and trabecular bone was also observed. FOBMD was diagnosed. A panoramic radiograph taken 6 months after the biopsy showed recovery of the trabecular bone structure.
