Bisphosphonates and tooth extraction: osteoporosis drugs, denosumab and the risk of osteonecrosis of the jaw

What is medication-related osteonecrosis of the jaw (MRONJ)?

Medication-related osteonecrosis of the jaw (MRONJ) is exposed, dead bone in the upper or lower jaw that has not healed for more than 8 weeks. The 2022 position paper of the American Association of Oral and Maxillofacial Surgeons (AAOMS) requires three conditions to be met at the same time for the diagnosis.

According to AAOMS, about 75% of cases of osteonecrosis of the jaw affect the lower jaw (mandible) and 25% the upper jaw (maxilla). It used to be called bisphosphonate-related osteonecrosis; the name was changed when similar lesions were described after denosumab and other drugs.

• Current or previous treatment with an antiresorptive drug, alone or together with immunomodulating or antiangiogenic drugs.
• Exposed bone, or bone that can be felt with a probe through a fistula in the maxillofacial region, persisting for more than 8 weeks.
• No history of radiotherapy to the jaws and no cancer metastases to the jaw bones.

Which osteoporosis drugs matter at the dentist?

What matters at the dentist are antiresorptive drugs, which slow down the breakdown of bone: bisphosphonates, denosumab and the newer romosozumab. According to the Scottish SDCEP guidance, people taking only calcium or vitamin D are not at risk of osteonecrosis of the jaw.

Bisphosphonates bind to bone and, as SDCEP notes, remain in the body for years, which is why the dentist also asks about drugs taken in the past. The effect of denosumab on bone remodelling wears off within a few months; SDCEP treats a patient as still on treatment for 9 months after the last dose.

If you cannot remember the name of the drug, the dentist may ask whether you have ever been prescribed a medicine for your bones, whether you take a tablet once a week or whether you have a drip for your bones. These prompting questions are suggested by SDCEP.

• Bisphosphonate tablets, often taken once a week: alendronic acid, risedronic acid and ibandronic acid.
• Bisphosphonates given as an intravenous infusion, for example zoledronic acid, which in osteoporosis is given once a year.
• Denosumab as an injection under the skin every 6 months; at a different dose, given monthly, it is used in patients whose cancer has spread to the bones.
• Romosozumab as injections under the skin, used to prevent fractures in women with osteoporosis.

How high is the risk of osteonecrosis with osteoporosis, and with cancer?

With osteoporosis treatment, the risk of MRONJ depends on the drug: AAOMS (2022) gives 0.02 to 0.05% for bisphosphonates and 0.04 to 0.3% for denosumab. With cancer treatment, which involves higher doses and often other drugs that add to the risk, it is clearly higher, usually below 5%; estimates from osteoporosis should not be applied to the treatment of bone metastases.

In osteoporosis studies, osteonecrosis also occurred in the placebo groups (0 to 0.02%), so the risk with bisphosphonates overlaps with the risk in people not taking the drug. The table sets out the AAOMS estimates, and the third column describes the usual approach according to SDCEP and AAOMS.

Apart from the reason for treatment itself, the risk is increased by the length of treatment, taking glucocorticoids (steroids) at the same time, and periodontal inflammation or inflammation of the tissues around the root tip. In cancer patients treated with zoledronic acid, wearing a denture was associated with a higher risk (odds ratio 4.9).

What symptoms can point to osteonecrosis of the jaw?

The typical sign of osteonecrosis of the jaw is exposed bone visible in the mouth, or an extraction wound that has still not healed after 8 weeks. At an early stage, which AAOMS calls stage 0, no bone is visible yet and the symptoms are non-specific.

The same symptoms also have many ordinary causes, such as dry socket, sinusitis or gum disease; AAOMS lists these as common misdiagnoses. Report them to your dentist and mention your medicines, because the SDCEP guidance advises patients to report such signs as soon as possible.

• Toothache with no visible cause in the tooth, or a dull ache in the bone, sometimes spreading towards the jaw joint (temporomandibular joint).
• Loose teeth that gum disease does not explain.
• Swelling in the mouth or on the face, pus or a fistula on the gum.
• Numbness, tingling or altered sensation in the lip or chin.
• Pain in the area of the maxillary sinus.
• An extraction socket that has still not healed after 8 weeks.

Why see a dentist before starting treatment?

A dental visit before antiresorptive treatment begins reduces the chance that teeth will have to be removed later. AAOMS (2022) cites a study of patients with prostate cancer that had spread to the bones, in which regular dental supervision was associated with a 2.5-fold lower relative risk of osteonecrosis than treatment only once symptoms appeared.

For cancer patients, AAOMS recommends a full dental examination with X-ray assessment before the first dose and the removal of teeth that cannot be saved. If the patient’s general condition allows, the drug is started only after the wounds have healed.

With osteoporosis the risk is much smaller, so there is no need to rush. The SDCEP guidance nevertheless recommends getting your teeth in order before treatment starts or as soon as possible afterwards, and removing teeth with a poor prognosis without delay. SDCEP also suggests the advice in the list below.

• Cut down on sugary snacks and drinks.
• Brush your teeth thoroughly with fluoride toothpaste.
• Stop smoking and limit alcohol.
• Go for regular dental check-ups.
• Have a denture that presses on the lining of the mouth adjusted or replaced.

Can a tooth be extracted while taking bisphosphonates?

Yes, a tooth can be extracted while you take bisphosphonates, and in people treated for osteoporosis the risk of osteonecrosis after an extraction is small: AAOMS (2022) gives 0 to 0.15%. With denosumab used for osteoporosis it was 1%, and in cancer patients treated with bisphosphonates 1.6 to 14.8%, with most estimates falling between 1 and 5%.

The SDCEP guidance divides patients into a low-risk and a higher-risk group. Low risk applies to people treated for osteoporosis with bisphosphonates for less than 5 years or with denosumab, without steroids; for them a simple extraction is carried out as usual. Higher risk applies to cancer patients, people who have had osteonecrosis before and those treated with bisphosphonates for more than 5 years or together with steroids.

In the higher-risk group the dentist first looks for a way to keep the tooth, for example by root canal treating it and leaving the root in place, free of inflammation, rather than removing it. If extraction is still the most appropriate treatment, it is carried out, and the patient comes back after 8 weeks for a check on healing.

SDCEP does not recommend antibiotics or antiseptic mouthwashes after an extraction solely to prevent osteonecrosis, because there is no evidence that they work for this purpose. AAOMS lists them among possible preventive measures, which is why any such medication is decided by the doctor case by case.

Do you need to stop bisphosphonates or denosumab before a tooth extraction?

Do not stop your osteoporosis medication on your own before a dental visit. A break in treatment, known as a drug holiday, is disputed: the AAOMS committee was split evenly on the question in 2022, and SDCEP writes that there is no evidence that a break from bisphosphonates reduces the risk, because these drugs stay in the bone for years.

According to SDCEP, the decision about a break belongs to the doctor who prescribed the drug, and the dentist should not discourage the patient from the treatment. AAOMS stresses that in people with osteoporosis the benefit of preventing fractures outweighs the risk of osteonecrosis.

Particular caution applies to denosumab, because after it is stopped bone loss speeds up and the risk of multiple vertebral fractures rises. SDCEP allows a non-urgent procedure to be planned for a month before the next injection is due, with the next dose given only after healing. If the doctor decides to pause the drug, AAOMS suggests the procedure 3 to 4 months after the last dose and restarting the drug 6 to 8 weeks afterwards; the timing is always agreed with the doctor in charge of your treatment.

Bisphosphonates and implants: can you have an implant with osteoporosis?

With osteoporosis treated with bisphosphonates, an implant is not contraindicated: the SDCEP guidance states that implant placement is not currently contraindicated in people with osteoporosis. AAOMS (2022) recommends that before the procedure the patient gives informed consent covering the small risk of osteonecrosis and of early and late implant loss, and then remains under regular long-term follow-up.

The data are inconclusive. Some reviews point to a higher risk with implants in the back of the jaws when bisphosphonate treatment has lasted more than 3 years and is accompanied by steroids, while others show no increase in risk. Osteonecrosis around an implant usually appeared late, after more than 12 months, often around implants placed before treatment started.

For cancer patients receiving antiresorptive drugs parenterally (by injection or infusion), AAOMS recommends avoiding implant placement. Other factors that affect how long an implant lasts are described in the article on whether implants last a lifetime.

How it works at DentalBlue

At DentalBlue in Białystok, a consultation before antiresorptive treatment or before a planned procedure can include an examination, a panoramic X-ray or a CBCT scan from the clinic’s own radiology unit, and a written treatment plan. In the clinic’s price list, “Wizyta bez bólu” (visit without pain: panoramic X-ray, consultation, examination and written treatment plan) costs 300 zł.

Surgical procedures are carried out under local anaesthesia or, for patients assessed as suitable, under general anaesthesia. Bring the name of the drug, when you started taking it and the date of the last dose or infusion. The final scope and cost are set at the consultation, and prices may change.