Osteoradionecrosis (ORN) of the jaw can be a complication of radiotherapy in patients having treatment to the head and neck region. ORN can range from an asymptomatic bone exposure that can remain stable for months to years and heal with conservative treatment, to severe bony necrosis with pathologic fracture necessitating surgical intervention.
Osteoradionecrosis is a delayed injury to an irradiated bone, where the bone becomes devitalised and exposed through a wound in the overlying skin or mucosa, with this wound not healing for 3-6 months.r
Incidence rates have been reported between 5 and 7% for patients having radiotherapy treatment to the head and neck region.
ORN develops most commonly after local trauma, such as dental extractions, biopsies, related cancer surgery, periodontal procedures, and even mouth ulcers, but it may also occur spontaneously. The reported mean time from completion of radiation therapy to the development of osteoradionecrosis varies and ranges from 22-47 months.r
There are multiple risk factors that predispose the development of ORN. These risk factors include:rr
- the location of the primary tumour (tongue, floor of mouth, tonsil and retromolar trigone)
- advanced stage tumours
- the dose to and volume of tissue irradiated
- previous surgery to the area irradiated
- dental extraction post radiotherapy
- continued alcohol and tobacco use
- poor oral hygiene.