What is bisphosphonate-related osteonecrosis of the jaw (BrONJ)?
Osteonecrosis of the jaw is a disorder where the blood supply to a bone stops or decreases and can cause an infection or bone death.
According to the American Dental Association: The typical clinical presentation of BrONJ includes pain, soft-tissue swelling and infection, loosening of teeth, drainage and exposed bone.These symptoms may occur spontaneously, or more commonly, at the site of previous tooth extractions.Patients may also present with feeling of numbness, heaviness and dysesthesias of the jaw.However, BrONJ may remain asymptomatic for weeks or months, and may only become evident after finding exposed bone in the jaw.
How is osteonecrosis identified and graded?
The following is a staging system used to identify this condition that the European Medicines Agency (EMA) will be using to further their research on this complication from oral and intravenous administration of bisphosphonates for use in cancer treatment and patients with osteoporosis and osteopenia.
In the U.S. we have grading from 1-4 from Asymptomatic to Severe.
Exposed or necrotic bone in patients who are asymptomatic, no evidence of infection.
Stage 2: _
Exposed or necrotic bone in patients with pain and clinical evidence of infection._
Stage 3: _
Exposed or necrotic bone in patients with pain, infection and one or more of the following: exposed and necrotic bone extending beyond the region of alveolar bone, resulting in pathologic fracture, extra-oral fistula, oral antral/oral nasal communication, or osteolysis extending to the inferior border of the mandibular or sinus floor._
How long must any of the symptoms be present to receive a diagnosis of BrONJ?
According to the American Dental Association (ADA) a patient must have exposed, necrotic bone in the oral cavity for 8 weeks.
What does necrotic mean in this presentation by patients who have used a bisphosphonate for either cancer or bone loss?
According to Wikipedia, necrosis is a form of cell injury that results in the premature death of cells in living tissue by autolysis.
Autolysis is the destruction of a cell by its own enzymes, within the body.
It is important to know that in the early stages of this disorder there may not be any specific symptoms, according to the EMA, other than bone pain that is not accompanied by exposed bone in the mouth.
Generally, this disorder is precipitated by oral surgery, involving the jaw bone, or the extraction of a tooth.
Routine procedures like crown placement, fillings or cleanings do not pose a risk for BrONJ because they don't involve cutting into the jaw bone.
Which drugs carry a risk for BrONJ?
The drugs that can cause osteonecrosis of the jaw are: Aclasta
® and the RANKL regulator, Prolia/Xgeva
The preceding medicines are used for cancer and bone loss.
The drugs that are given more frequently to prevent bone cancer, cause a much greater risk of BrONJ to the patient than the same bisphosphonates used for bone loss.
The dosing for cancer patients is much more frequent than the dosing for bone loss.
How is osteonecrosis of the jaw treated?
Treatment indications vary, but the common component seen with this treatment is removal of the affected bone and the use of oral antibiotics in a rinse or capsule.
Lesions generally appear above the necrotic bone, and the number of these determines the grading from 1-4.
What precautions can we take to prevent this while using a bisphosphonate?
You should try to avoid dental extractions or any procedure that is considered invasive.
You should maintain good oral hygiene, have ongoing checkups and cleaning, and report any symptoms like tooth loosening, pain or swelling.
This disorder is very serious; but it is also considered rare for those taking these drugs orally for the treatment of bone loss.
If you are receiving an intravenous dose for bone loss or cancer, speak to your oral surgeon or dentist about any precautions you may need to take because the risk is higher in these individuals.
- American Dental Association. (January 22, 2009) Study Finds Higher Incidence of Osteonecrosis of the Jaw in Alendronate Users.
Accessed March 24, 2015 from:
- Flores, Pamela.
(April 01, 2009). News on Osteonecrosis of the Jaw from the ADA and NOF. Accessed March 24, 2015 from: http://www.healthcentral.com/osteoporosis/c/76444/65601/osteonecrosis
- European Medicines Agency.
(September 24, 2009) CHMP Assessment Report on Bisphosphonates and Osteonecrosis of the Jaw.
Accessed March 24, 2015 from:
Pam is a patient educator and digital health writer who has worked for Remedy Health Media on their osteoporosis web site since 2008.Pam is also a group leader and moderator with the National Osteoporosis Foundation Inspire online community.