From the FDA Drug Label
Osteonecrosis of the jaw (ONJ) has been reported in patients treated with bisphosphonates, including zoledronic acid. Most cases have been in cancer patients treated with intravenous bisphosphonates undergoing dental procedures. The risk of ONJ may increase with duration of exposure to bisphosphonates. Concomitant administration of drugs associated with ONJ may increase the risk of developing ONJ
The chance of osteonecrosis of the jaw in breast cancer patients treated with zoledronic acid is a potential risk, particularly in those undergoing dental procedures or with a history of concomitant risk factors such as cancer, chemotherapy, or radiotherapy 1.
- Key risk factors for ONJ include:
- Cancer
- Chemotherapy
- Angiogenesis inhibitors
- Radiotherapy
- Corticosteroids
- Poor oral hygiene
- Pre-existing dental disease or infection
- Anemia
- Coagulopathy It is essential to perform a routine oral examination before initiating bisphosphonate treatment and to consider dental examination with preventive dentistry in patients with a history of concomitant risk factors.
From the Research
The risk of osteonecrosis of the jaw (ONJ) in breast cancer patients is approximately 2.8% at 3 years, primarily associated with bone-modifying agents such as zoledronic acid. The most recent and highest quality study, 2, found that the cumulative incidence of ONJ at 3 years was 2.8% in patients receiving zoledronic acid for bone metastases. Key risk factors for ONJ include:
- Cancer type, with myeloma having the highest risk
- Oral health, with fewer total number of teeth and presence of dentures increasing the risk
- Frequency of dosing, with planned zoledronic acid dosing intervals of less than 5 weeks being more likely to experience ONJ
- Current smoking, which doubles the risk of ONJ To minimize ONJ risk, patients should:
- Complete necessary dental procedures before starting these medications
- Maintain excellent oral hygiene
- Have regular dental check-ups
- Avoid invasive dental procedures while on treatment if possible
- Inform their dentist about their medication regimen
- Consider smoking cessation and limiting alcohol consumption to reduce risk. The development of ONJ is attributed to the inhibition of bone remodeling and angiogenesis by these medications, leading to compromised healing of the jawbone after trauma or infection, particularly in an environment constantly exposed to oral bacteria, as supported by 3, 4, 5, and 6.