Recently an association between bisphosphonate use and a rare dental condition termed 'osteonecrosis of the jaw' (ONJ) has been reported. Patients with osteoporosis and Paget disease who take bisphosphonates have a significantly reduced risk of fracture and other skeletal complications. This represents significant health benefits, against which the small risk of ONJ needs to be considered. In patients with bone malignancy, the risk of ONJ needs to be balanced against the benefit of therapy on the underlying malignancy. There are still many uncertainties about this condition. This position paper seeks to summarise what is currently known about ONJ to provide information to medical practitioners and dental practitioners.