Bisphosphonate therapy for skeletal malignancies and metastases: impact on jaw bones and prosthodontic concerns

Healthy jawbones ensure better tooth anchorage and the ability to masticate and maintain metabolism. This is achieved by a delicate balance between bone formation and resorption in response to functional demands. An imbalance in the expression of receptor activator of nuclear factor kappa-B (RANK) ligand (RANKL) and osteoprotegerin (OPG) or osteoclastogenesis inhibitory factor (OCIF) is believed to be the underlying mechanism of osteolysis in metastases, multiple myelomas, and cancer therapy-induced bone loss in patients. Considered mainly as bone-specific agents to treat postmenopausal osteoporosis, bisphosphonates, in combination with certain chemotherapeutic agents have proved to be effective in prevention of tumor formation and metastatic osteolysis in bone tissue. Osteonecrosis of the jaws associated with them has, however, been of grave concern to the prosthodontist, as it predisposes patients to a bone-deficient basal seat for dental prostheses. This manuscript reviews available information over the past 13 years on possible mechanisms of bone loss, bisphosphonate-induced osteonecrosis of jaw bones, and prosthodontic concerns.