Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a rare but potentially severe condition, and the etiopathology and risk factors are poorly defined. The American Association of Oral and Maxillofacial Surgeons position paper on BRONJ update 2009 remarks all the risk factors of developing BRONJ. Local anatomy such as lingual tori, mylohyoid ridge or palatal tori, and areas with thin mucosa overlying bony prominences represent some of these local factors. We have recently treated a patient presenting a mandibular osteonecrosis involving a rigid miniplate which had been placed 18 years ago during a surgical excision of a radicular cyst. The patient, a 70-year-old female, did not show any other risk factors which could expose her to BRONJ, such as cortisone therapy, head and neck radiotherapy, chemotherapy, periodontal disease, or other.