Osteoporosis Medications: Bisphosphonates and Jaw Necrosis Risks
When you’re told you have osteoporosis, the goal is simple: keep your bones strong so you don’t break a hip, spine, or wrist. For millions of people, that means taking a daily or weekly pill like alendronate (Fosamax), risedronate (Actonel), or ibandronate (Boniva). These are bisphosphonates - drugs that slow down bone loss and cut fracture risk by up to 70%. But somewhere in the fine print, there’s a warning: jaw necrosis. It sounds scary. And it’s real. But how real is it for you?
What Exactly Is Jaw Necrosis?
Medication-related osteonecrosis of the jaw, or MRONJ, is when part of the jawbone dies and becomes exposed through the gums. It doesn’t happen overnight. It usually shows up as a patch of bone sticking out after a tooth extraction, denture irritation, or even a routine cleaning. The area won’t heal. It might hurt. It might get infected. And it lasts more than eight weeks. That’s the official diagnosis.
This isn’t radiation damage. It’s not cancer. It’s caused by drugs that stop your body from breaking down old bone - a process called resorption. Bisphosphonates lock onto bone tissue and shut down the cells (osteoclasts) that do the cleanup. That’s great for your spine and hips. But your jaw? It’s different. It’s constantly moving. It’s full of bacteria. It heals slower. And it’s the only bone in your body that’s exposed to the outside world through your mouth.
How Common Is This Really?
Let’s get numbers out of the way. If you’re taking oral bisphosphonates for osteoporosis, your risk of jaw necrosis is about 0.7 in 100,000 people per year. That’s less than one case per 140,000 patients annually. To put that in perspective: you’re more likely to be struck by lightning than develop MRONJ from Fosamax.
Compare that to cancer patients getting high-dose IV bisphosphonates. For them, the risk jumps to 1 in 100, or even higher with denosumab (Prolia). But osteoporosis patients? The data is clear: the risk is tiny. A 2011 study of 260,000 people found no increased risk of jaw necrosis in those taking oral bisphosphonates compared to those who didn’t.
Still, it happens. And when it does, it’s serious. One woman on the National Osteoporosis Foundation forum spent 18 months dealing with antibiotics and surgery after a cleaning exposed bone. But another man took Fosamax for 22 years, had multiple extractions and implants, and never had a problem. There’s no one-size-fits-all outcome.
Why Does the Jaw Get Hit So Hard?
It’s not random. Your jawbone turns over 10 times faster than your thigh bone. That means it absorbs more of the drug. Bisphosphonates cling to bone like glue - and they stick around for years, even decades. Once you take them, they’re in your skeleton for life.
On top of that, the jaw has thin gum tissue, constant bacterial exposure, and mechanical stress from chewing. A small cut from a toothbrush, a loose crown, or a tooth pulled without proper care can trigger a chain reaction. The bone can’t heal because the drugs are blocking the cells that rebuild it. The infection sets in. The bone dies.
That’s why dentists stress prevention. If you’re about to start bisphosphonates, get a full dental exam first. Fix cavities. Pull rotten teeth. Get your gums healthy. Don’t wait until you’re on the drug. Once you’re on it, your mouth becomes a minefield.
Oral vs. IV: Big Difference in Risk
Not all bisphosphonates are created equal. Oral pills (alendronate, risedronate) are low-dose and barely absorbed. Less than 1% of what you swallow actually reaches your bones. That’s why the risk is so low.
But IV versions like zoledronic acid (Reclast) are a different story. You get a full 5-milligram dose dumped straight into your bloodstream once a year. That’s way more drug hitting your bones. And yes, the risk of jaw necrosis goes up - but still only to about 1 in 100,000 per year for osteoporosis patients. That’s still far lower than cancer patients who get 4mg monthly.
And then there’s denosumab (Prolia). It’s not a bisphosphonate - it’s a monoclonal antibody. It works differently, but it also stops bone breakdown. And guess what? Studies show it carries a 1.7 to 2.5 times higher risk of jaw necrosis than oral bisphosphonates. Yet many doctors still choose it because it’s easier to take (just two shots a year) and works just as well at preventing fractures.
What About Stopping the Drug?
Here’s the tricky part. If you’re worried about jaw necrosis, maybe you think: “I’ll just stop taking it.” But that’s not a simple fix.
A 2024 study in Nature Communications looked at over 600 patients. They found that if you stop IV bisphosphonates for more than a year, your risk of jaw necrosis drops by 82%. Sounds great, right? But here’s the catch: stopping also raises your fracture risk by 28%. That’s a big trade-off. One woman in her 70s stopped zoledronic acid because she was scared of jaw problems - then broke her hip six months later.
For oral bisphosphonates, the data isn’t as clear. There’s no proven “drug holiday” window. The drug stays in your bones for years anyway. So stopping won’t erase the risk - it just removes the benefit.
What Should You Do?
If you’re on bisphosphonates:
- Keep your mouth healthy. Brush, floss, and see your dentist every six months.
- Tell your dentist you’re on a bisphosphonate or denosumab. Don’t assume they know.
- Don’t delay needed dental work. A root canal or crown is safer than pulling a tooth after you’ve been on the drug for years.
- Avoid invasive procedures if you can. But if you need an extraction, do it early - before you’ve been on the drug for more than three years.
- Don’t panic over a small sore. Most mouth ulcers aren’t MRONJ. But if something doesn’t heal in two weeks, get it checked.
If you’re thinking about starting bisphosphonates:
- Get a dental checkup first. Fix everything you can.
- Ask your doctor: “Is this the best option for me?” There are alternatives like romosozumab or teriparatide, especially if you have a history of dental issues.
- Understand the trade-off: You’re trading a tiny risk of jaw necrosis for a huge drop in fracture risk.
The Bigger Picture
Over 8 million Americans take bisphosphonates for osteoporosis. About 72% of eligible patients are on treatment. But 38% quit within a year - mostly because of stomach upset, not jaw problems. That tells you something. The real barrier isn’t fear of necrosis. It’s the side effects you feel every day.
And here’s what doctors know: the risk of breaking a hip at 75 is far worse than the risk of jaw necrosis. A broken hip means months in the hospital, loss of independence, and a 20% chance of dying within a year. Bisphosphonates cut that risk by over half.
The American Dental Association, the American Association of Oral and Maxillofacial Surgeons, and the National Osteoporosis Foundation all agree: the benefits outweigh the risks. For most people.
But “most” doesn’t mean “all.” If you have severe gum disease, are a smoker, or have diabetes, your risk goes up. If you’ve had radiation to your head or neck, you’re in a different category entirely. That’s why personalized care matters.
What’s Next?
Doctors are starting to look at biomarkers - like urine tests that measure bone turnover - to see who’s at highest risk for MRONJ. In the next few years, we may be able to say: “You’re low risk. Stay on the drug.” Or: “You’re high risk. Switch to something else.”
Until then, the advice is simple: don’t let fear stop you from protecting your bones. But do protect your mouth. Stay on top of dental care. Talk to both your doctor and your dentist. And remember: you’re not alone. Millions are on these drugs. Very few ever face jaw necrosis. But those who do? They’re the reason we pay attention.
Can bisphosphonates cause jaw necrosis even if I’ve never had dental work?
Yes, but it’s extremely rare. Most cases occur after a dental procedure like an extraction or implant. However, a small number of patients develop exposed bone without any known trigger - often due to underlying gum disease or infection that went unnoticed. Regular dental checkups help catch problems early.
Is MRONJ reversible?
In early stages (Stage 1), MRONJ can often be managed with antibiotics, mouth rinses, and careful cleaning. Some cases heal over time, especially if the drug is stopped and the patient avoids trauma to the jaw. But once the bone is exposed and infected for months (Stage 2 or 3), surgery is often needed. Full recovery is possible, but it takes months and isn’t guaranteed.
Should I stop taking alendronate before a tooth extraction?
For oral bisphosphonates, stopping the drug is not routinely recommended. The drug stays in your bones for years, so pausing it won’t lower your risk much. Instead, the focus is on timing: get dental work done early, ideally before you’ve been on the drug for more than three years. For IV bisphosphonates, a drug holiday of 3-6 months may be considered - but only after discussing fracture risk with your doctor.
Does denosumab (Prolia) have a higher risk than bisphosphonates?
Yes. Studies show denosumab carries a 1.7 to 2.5 times higher risk of jaw necrosis compared to oral bisphosphonates. This is likely because it works more powerfully and rapidly to suppress bone turnover. However, its fracture prevention is just as strong. The choice between them depends on your dental health, overall risk, and ability to maintain regular dental care.
How do I know if I’m at higher risk for MRONJ?
You’re at higher risk if you have: gum disease or tooth infections, diabetes, poor oral hygiene, smoke, take steroids, or have had radiation to the head/neck. Also, if you’ve been on IV bisphosphonates for more than three years, or are on denosumab, your risk increases. Talk to your dentist and doctor about your full medical history before starting any treatment.
Final Thought
You’re not choosing between perfect safety and danger. You’re choosing between two risks: the risk of a broken bone, and the risk of a rare jaw problem. For most people, the broken bone is the bigger threat. But that doesn’t mean you ignore the other. Stay informed. Stay proactive. And never let fear keep you from protecting what matters most - your ability to move, stand, and live without pain.
