Osteoradionecrosis--a review of current concepts in defining the extent of the disease and a new classification proposal.

Osteoradionecrosis (ORN) is potentially a debilitating and serious consequence of radiotherapy to the head and neck. Although it is often defined as an area of exposed bone that does not heal, it can also exist without breaching the mucosa or the skin. Currently, 3 classifications of ORN are in use, but they depend on the use of hyperbaric oxygen or are too complicated to be used as a simple aide-mémoire, and include features that do not necessarily influence its clinical management. We propose a new classification to cover these shortcomings and to take into account the increasingly widespread use of antifibrotic medical treatment. We classified a series of 85 patients with varying severities of ORN into 4 groups. An analysis of the outcomes of the series showed that the classification staged the severity of the condition simply and that the stage was relevant to both treatment and outcome. The new classification was therefore verified by the series presented.