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During Treatment

What is Osteonecrosis of the Jaw?

Osteonecrosis of the Jaw (ONJ) is a serious condition of the jaw. It happens when areas of dead bone become exposed and do not heal. It can happen on its own, because of dental disease, or following dental therapy.

You are at a higher risk of ONJ because you are on a bone-modifying therapy.

This group of drugs may include:

  • Pamidronate (Aredia®)
  • Zoledronic Acid (Zometa®)
  • Clodronate (Bonefos®)
  • Denosumab (Xgeva®)

 

In rare instances, bone-modifying therapy can lead to destruction of the jawbone, or ONJ. Always tell your cancer doctor/nurse about your dental history and if you need any dental procedures.

Signs of ONJ

A diagnosis for ONJ is made by a dentist or a doctor. Signs may include:

  • Loosening of a tooth/teeth
  • Swelling of soft tissue (like the gums)
  • Infection of soft tissue (e.g. redness, pain, drainage)
  • Tooth or jaw pain (when the jaw feels heavy or numb)
  • Exposed bone in jaw area

If you feel ANY of the symptoms above tell your cancer care team as soon as possible.

Call the WRHN Cancer Centre call centre at 519-749-4380, Monday to Friday, from 8:30 a.m. to 4:00 p.m. After-hours support is available through CareChart Digital Health at: 1-877-681-3057.

How Can I Prevent ONJ?

Have a dental exam and complete any dental work before starting a bone-modifying therapy. Keep your dentist informed of what drug you are taking. You can continue to have dental cleaning and fillings.
Avoid elective or surgical procedures in the mouth during treatment with bone-modifying therapy (such as dental extraction or crown lengthening surgery). It is better to try and keep existing teeth and roots, if able.

 

While on bone-modifying therapy, talk to your doctor/nurse before you have any urgent or elective dental/oral procedures. This helps lessen the risk of ONJ as a result of dental procedures while on a bone-modifying therapy.

Your cancer healthcare team will:

  • Plan how long you will need to be off your bone-modifying therapy before and after your procedure.
  • Your dentist may choose to prescribe an antibiotic to take or a use a special mouth rinse to use.

Tips to Care For Your Mouth

  • Stop smoking
  • Avoid drinking alcohol in excess
  • Keep your mouth moist with water (lowers risk of decay)
  • Brush your teeth after meals and at bedtime
  • Floss your teeth daily, unless advised not to by your doctor or dentist.
  • Check your teeth and gums daily in the mirror
  • Have your dentures fit checked regularly in case adjustments are needed to avoid irritation or trauma. A dentist should also check your oral health.
  • Have a dental exam every 6 to 12 months (routine cleaning and fillings are safe)
  • Contact your dentist right away for any concerning symptoms or changes in your oral health.
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About This Resource

Author: Waterloo Wellington Regional Cancer Program

Revised: March 2026

PEM#: WRHNCC0062

Download this Resource (PDF)

Use this resource for your information only. It does not replace medical advice from your doctor or other healthcare professionals.

Email: [email protected]

Website: www.cancerwaterloowellington.ca

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