Osteoradionecrosis (Bone Death)

Patients who receive radiation therapy for their head and neck cancer are at risk of developing osteoradionecrosis, or bone death, in the lower jaw (mandible). Although rare, osteoradionecrosis can also affect the upper jaw (maxilla). This condition impacts approximately 3-10% of patients and can occur even years after radiation therapy has ended.

What Causes Osteoradionecrosis?

Osteoradionecrosis (ORN) is caused when radiation therapy damages the blood vessels that supply the jawbone with nutrients and oxygen. Without an adequate blood supply, the bone can no longer heal itself when faced with infection or trauma, and it dies. The lower jaw is particularly at risk due to its already limited blood supply.

The risk of ORN increases with higher doses of radiation, or if the jawbone is exposed during treatment. Other risk factors include poor nutrition; poor oral hygiene before, during and after treatment; dry mouth that develops after radiation treatment; and any trauma to the jawbone, including things like tooth extractions, surgeries, placement of dental implants, or accidents, especially those that occur within the first year following treatment. Sometimes ORN occurs without damage or trauma to jaw.


Symptoms of ORN include:

  • Pain
  • Swelling
  • A sore in the mouth or on the jaw
  • Trismus, or difficulty opening the mouth
  • Development of a fistula, or opening, between the jaw and the surface of the face or neck
  • Decreased or total loss of feeling in the mouth, jaw or lip
  • Infection
  • Jaw fracture that is not the result of an accident or other trauma
  • Presence of exposed bone inside the mouth
  • Bone fragments that stick out through the skin of the face


If symptoms are present, your doctor will try to find the cause or extent of your ORN. This usually includes doing a physical exam, a complete head and neck exam, and reviewing your medical records to find out the total dose of radiation you received and the area that was treated. Your doctor will also order tests, which may include x-rays of the jaw, a CT scan, and MRI, or a biopsy of the jaw to check for recurrent or secondary cancer.

Your doctor will give your ORN a grade, which depends on its location, response to treatment, and whether any fractures have occurred.  The grade will then help them determine the best treatment options. ORN grades are as follows: 

  • Grade I: Soft tissue has died resulting in persistent exposure of the underlying bone.
  • Grade II: Osteoradionecrosis that has not responded to treatment.
  • Grade III: Osteoradionecrosis affects the whole thickness of the bone, has caused a fracture, or a draining tract to the overlying skin (fistula).

Management & Treatment

Your doctor will suggest management and treatment options based on the extent of your ORN.  These options may include:

  • Antibiotic medications, if infection is present.
  • Surgical debridement, or removal of dead or infected tissue. This may include removal of dead or infected bone (also called sequestrectomy).
  • Reconstructive surgery to restore blood flow, replace sections of jawbone that were removed, or graft soft tissue to replace muscle or tissue that was removed.
  • Hyperbaric oxygen therapy, which involves breathing pure oxygen in a pressurized chamber. This treatment is helpful in delivering more oxygen to damaged tissue, which improves blood supply and promotes healing.

More Tips for Preventing and Managing ORN

Before Radiation Therapy
  • Get a complete oral and dental evaluation and fully treat any active dental disease. This includes completing any necessary tooth extractions or fillings, addressing any gum disease, ensuring dentures fit properly, etc.
  • Tell your dentist you will be having radiation to the head and neck, and ask about starting daily fluoride treatments.
During and After Radiation Therapy
  • Always practice good oral hygiene, including before, during, and after treatment. Keeping your mouth, teeth, and gums healthy will aid in preventing infection or dental care-related traumas (e.g., tooth extractions) that may lead to development of ORN.
  • Be sure to use the fluoride treatments recommended to you by your dentist or medical team. These treatments help prevent cavities and other dental issues.
  • If you have dry mouth, make sure to keep your mouth moist with any saliva replacements or strategies recommended to you by your dentist or medical team.
  • See your dentist regularly. As a cancer survivor who received radiation, this may mean seeing your dentist every 3 or 4 months, instead of every 6.
  • Maintain proper nutrition with a healthy diet that is low in sugar.
  • If you develop dental problems, especially those that may need a dental extraction, be sure to inform your dentist of your history of radiation therapy. If extractions are needed, it may be necessary to get hyperbaric oxygen treatments before and after extraction in order to reduce the risk of developing ORN.

  • Fan, Huan, et al. “New Approach for the Treatment of Osteoradionecrosis with Pentoxifylline and Tocopherol.” Biomaterials Research, BioMed Central, 29 Sept. 2014, www.ncbi.nlm.nih.gov/pmc/articles/PMC4552457/.
  • “Institute For Head, Neck & Thyroid Cancer.” Mount Sinai Beth Israel, www.headneckandthyroid.com/Patients/Osteoradionecrosis.
  • “Osteoradionecrosis - Canadian Cancer Society.” Www.cancer.ca, www.cancer.ca/en/cancer-information/diagnosis-and-treatment/managing-side-effects/osteoradionecrosis/?region=bc.
  • “Osteoradionecrosis.” The Oral Cancer Foundation, 15 Oct. 2018, oralcancerfoundation.org/complications/osteoradionecrosis/.