OBJECTIVES: Multiple myeloma (MM) is characterized by the occurrence of osteolytic lesions. MM treatment usually involves antiresorptive drugs (mainly bisphosphonates).

CASE REPORT: A patient with an MM presented osteolytic lesions of the mandible. Extraction of teeth 45 and 46 was performed 5 years after the diagnosis of periodontitis. Four months later, osteonecrosis of the jaw (ONJ) was diagnosed at the extraction site. X-ray showed an extension of osteolytic lesions on the right side, close to the extraction site, without modification of the lesions on the left side. Two months later, a curettage was performed because of a painful bone sequestration. X-ray showed an extension of the osteolytic lesions on the right side.

RESULTS: Histological analysis found a vascularized plasmacytoma of the soft tissues around the ONJ. Analysis of the bone showed mixed lesions with osteonecrotic areas and living bone resorbed by active osteoclasts surrounding a plasmacytoma. The surface area of the osteolytic foci has considerably increased only close to the extraction site.

CONCLUSIONS: Tooth extraction triggered an ONJ associated with bisphosphonate treatment. However, it also seemed to induce a considerable proliferation of plasma cells at the extraction site; we hypothesize that it is due to the increase in bone remodeling related to the surgical trauma.