ビスフォスフォネートが原因と考えられる下顎骨壊死の一例

発症機序と予防に関する考察

抄録

There are two types of anti-bone resorptive bisphosphonates, nitrogen-containing bisphosphonates (NBPs) and non-nitrogen containing bisphosphonates (non-NBPs). Since NBPs have much stronger activities than non-NBPs, the former are widely used to treat increased bone resorption (including bone metastasis). In addition to the known inflammatory side effects of NBPs, recent clinical application has been associated with an unexpected side effects, necrosis, and subsequent exposure of jaw bones. We report mandibular osteonecrosis in a 63-year-old woman who had breast cancer with bone metastasis. She was referred to our clinic because of oral pain. The mandible (partly exposed because of necrosis) was surrounded by inflamed soft tissue. She had been taking pamidronate (an NBP) once a month (45mg) for 35 months. In Europe and the United States, several thousand cases of NBP-related osteonecrosis have been reported during the past 3 years. On clinical examination, we diagnosed NBP-related osteonecrosis. This case emphasizes the importance of close communication between oncologists and dentists before and during treatment with NBP. On the basis of the current results of our basic studies of BPs, we discuss possible mechanisms underlying jaw necrosis and means of prevention.