Osteoradionecrosis of the jaws: definition, epidemiology, staging and clinical and radiological findings. A concise review

Abstract

Osteoradionecrosis (ORN) of the jaws is a pernicious complication of radiation therapy for head and neck tumours. This article aims to provide an update on data related to the definition, epidemiology, staging, and clinical and radiological findings of ORN of the jaws. Using certain keywords, an electronic search was conducted spanning the period from January 1922 to April 2014 to identify the available related investigations. Pooled data were then analysed. ORN is described as exposed irradiated bone that fails to heal over a period of 3 months without evidence of persisting or recurrent tumour. The prevalence of ORN varies in the literature. Several staging or scoring systems of ORN have been proposed. Clinical findings include ulceration or necrosis of the mucosa with exposure of necrotic bone. Radiological findings are not evident in the early stages of ORN. Furthermore ORN may not be apparent in imaging even when the disease is advanced. Taking into account the severity of ORN and the difficulties in diagnosing it early and accurately, the clinician should be aware of this complex entity in order to prevent its appearance or the development of more severe complications.

Keywords: Clinical findings; epidemiology; jaw; osteoradionecrosis; radiation therapy.

Figure 1.

A 69-year-old man presented with pain and a non-healing wound in the left lower jaw. The patient was an active smoker, suffered from pharynx cancer and had received radiotherapy (external beam radiotherapy with standard field sizes, conventional fractionation and mean dose 64 Gy) and chemotherapy. Clinically, exposed necrotic bone in the left lower jaw, inflammation, swelling and inferior alveolar nerve hypesthesia was present (a). The orthopantomogram revealed pathologic fracture of the left lower jaw (b). The patient was diagnosed with osteoradionecrosis of the lower jaw and was scheduled to be treated surgically.

Figure 2.

Orhtopantomograms of patients who have received radiotherapy (external beam radiotherapy with standard field sizes, conventional fractionation and mean dose 64 Gy) for oropharyngeal cancers. The patients underwent extractions of teeth of the lower jaw after completion of radiotherapy. The orthopantomogram revealed radiolucencies indicating post extraction sockets, which remained visible for longer than 12 months (a), as well as increased radiodensity with mixed radio-opaque/radiolucent lesions, where the radiolucent areas represent bone destruction (b).