Can Alendronate Cause Teeth Problems?

Alendronate, one of the most widely prescribed osteoporosis drugs, can cause dental problems, though the risk is lower than many patients fear. The two main oral complications are osteonecrosis of the jaw, a condition where bone tissue in the jaw dies and becomes exposed, and painful ulcers in the mouth’s soft tissue. Both are uncommon but worth understanding, especially if you need dental work while on the medication.

Osteonecrosis of the Jaw

The dental problem most associated with alendronate is osteonecrosis of the jaw, often shortened to ONJ. This is a condition where a patch of jawbone loses its blood supply, dies, and becomes exposed through the gum tissue. The exposed bone persists for weeks without healing. Multiple authors have reported ONJ linked specifically to oral bisphosphonates like alendronate.¹ The condition is painful, can make eating difficult, and sometimes leads to infection in the surrounding bone and tissue.

Before you panic, the numbers matter here. A large Danish study following over 60,000 alendronate users found the rate of surgically treated ONJ was about 2.5 cases per 10,000 person-years of use.² That means the vast majority of people who take alendronate will never develop this complication. But the risk is not zero, and it climbs the longer you stay on the drug.

How Alendronate Affects Jawbone Healing

Alendronate works by slowing down the cells that break down old bone, which is exactly what you want when treating osteoporosis. The problem is that the jaw relies heavily on constant bone turnover, more so than most other bones in your body, because it absorbs daily mechanical stress from chewing and is closely connected to the teeth and gum tissue. When alendronate suppresses that remodeling process too aggressively, the jawbone loses its ability to repair small injuries or respond to infection.

Animal research has shown that alendronate doesn’t necessarily reduce the number of bone-resorbing cells, but it does increase the number of empty spaces within the bone where living cells should be. That suppression of normal bone turnover appears to be the core problem.³ The jaw is uniquely vulnerable because it is one of the few bones in the body that is directly exposed to the outside environment through the thin gum tissue, making it susceptible to bacteria when healing stalls.

Oral Ulcers From Alendronate

A less well-known side effect is mouth ulcers. Alendronate tablets are chemically irritating, and if the pill lingers in contact with the soft tissue of the mouth, cheeks, or gums instead of being swallowed quickly, it can cause painful chemical burns. A review of reported cases found that alendronate can produce severe mucosal ulcerations in the mouth, causing intense pain and significant problems with eating and drinking.⁴ The good news is that these ulcers typically heal once the person stops taking the drug or fixes how they take it.

Case reports highlight that this problem hits hardest when patients don’t follow swallowing instructions closely. In one case, an elderly woman with dementia developed severe oral ulceration because the tablet was not swallowed properly. In another, a patient with learning difficulties routinely “pouched” medications in her cheeks, leading to chemically induced ulceration in the lower cheek area.⁵ Caregivers for older adults or anyone who has trouble swallowing pills should pay special attention to how alendronate is taken. The standard instructions exist for a reason: swallow the tablet whole with a full glass of water, stay upright for at least 30 minutes, and don’t chew or crush it.⁶

What Triggers Jaw Problems

Not everyone on alendronate faces the same level of risk for osteonecrosis. Several factors raise the odds considerably. The biggest one, by far, is invasive dental work, especially tooth extraction. In one study of osteoporosis patients on alendronate, tooth extraction was the single strongest independent predictor of ONJ, with roughly a tenfold increase in odds compared to those who didn’t have teeth pulled.⁷ That same study found that using alendronate for more than three years tripled the risk, and having rheumatoid arthritis alongside osteoporosis raised it roughly fivefold.

Periodontal disease, the chronic gum infection that loosens teeth and eats away at the bone supporting them, is another major contributor. A national cohort study of over 27,000 women on bisphosphonates found that periodontal disease on its own raised the risk of ONJ, and when periodontal disease and tooth extraction both occurred, the risk more than doubled compared to patients with neither.⁸ Animal research has confirmed the link: when aggressive periodontitis was induced in rats receiving a potent bisphosphonate, osteonecrosis developed at the site of the gum disease.⁹

Duration of alendronate use matters as well. A systematic review found that ONJ risk increases after more than five years of therapy, and the cumulative incidence climbs steadily, from about 0.23% after two years of treatment to about 0.92% after ten years.¹⁰ This is one reason many clinicians discuss a “drug holiday” after five years of continuous use.

Dental Implants While on Alendronate

If you’re on alendronate and need a dental implant, the picture is more reassuring than you might expect, with one important caveat. A recent meta-analysis pooling data from multiple cohort studies found that implant failure rates were not significantly higher in people taking antiresorptive drugs like alendronate. A sensitivity analysis at the implant level actually suggested lower failure rates in treated patients, though the certainty of that evidence was rated very low.¹¹ Alendronate’s bone-preserving effects may actually help the implant integrate with surrounding bone, which would explain why the implants themselves tend to hold.

The caveat is ONJ triggered by the implant surgery. That same meta-analysis identified 186 cases of ONJ among implant recipients and estimated a pooled ONJ rate of about 0.5% following implant placement in patients on antiresorptive therapy. One risk-adjusted analysis found bisphosphonates increased ONJ by about 3 additional cases per 1,000 patients.¹¹ A separate systematic review noted that when ONJ did occur in implant patients, the lower jaw was the more common location, with about twice as many mandibular cases as maxillary ones.¹²

One practical note: when osteonecrosis does develop in patients taking oral bisphosphonates like alendronate, it tends to affect fewer sites and require fewer surgeries than in patients receiving intravenous bisphosphonates. In a study comparing the two groups, oral bisphosphonate patients averaged about one involved site and roughly one surgery, while IV patients averaged more sites and more procedures, with worse overall outcomes.¹³

Do Drug Holidays Help Before Dental Work?

Many dentists and physicians discuss pausing alendronate before a major dental procedure, hoping the bone’s healing capacity will recover during the break. The logic seems straightforward, but the evidence is surprisingly thin. One study examining outcomes after tooth extraction found limited evidence that stopping bisphosphonates for several months beforehand actually reduced the development of ONJ.¹⁴

The reason drug holidays may disappoint is that alendronate lingers in bone tissue for years after you stop taking it. A study examining the bone-resorbing cells of patients who had stopped their oral bisphosphonate found that those cells were still suppressed in the vast majority of cases. Even among patients who had been off the drug for six months or longer, three out of four still showed suppressed bone cell activity.¹⁵ This doesn’t mean drug holidays are useless in every case, but it does mean they’re not the reliable safety net many patients and providers assume them to be.

How Jaw Osteonecrosis Is Treated

If ONJ does develop, treatment depends on how advanced the disease has become. Early-stage cases, where there is exposed bone but no symptoms or infection, often respond to conservative measures: antimicrobial mouth rinses, careful monitoring, and stopping or switching the bisphosphonate if the prescribing physician agrees. More advanced cases with pain, infection, or expanding dead bone typically require surgical removal of the affected tissue.¹⁶ A systematic review comparing the two approaches found that surgery produced better outcomes in advanced cases, while conservative treatment worked reasonably well for patients caught early with minimal symptoms.

The takeaway is that early detection makes a real difference. Some clinicians use dental X-rays to look for “ghost sockets,” areas where a tooth was removed but the socket fails to fill in with new bone as expected. A ghost socket is a sign that the jawbone’s normal repair process has stalled, and catching it early can prevent more serious damage from developing.

Can a Blood Test Predict Your Risk?

There has been a lot of interest in using a blood marker called CTX (C-terminal telopeptide), which reflects how actively your body is breaking down bone, to predict who might develop ONJ after dental surgery. The idea is appealing: a simple blood draw that tells your dentist whether it’s safe to proceed. A meta-analysis found that among osteoporosis patients on oral bisphosphonates, a CTX level above 260 pg/mL was associated with an extremely low risk of ONJ after oral surgery.¹⁷

That sounds promising, but the picture is muddier in practice. A separate retrospective study concluded that CTX levels alone are not reliable as a predictive or preventive measure for ONJ.¹⁸ CTX levels fluctuate based on the time of day, recent food intake, and other medications. Some dentists still order the test as one piece of a larger risk assessment, but no one should treat it as a definitive green or red light.

Putting the Risk in Perspective

With all the alarming language around jaw death and bone exposure, it’s easy to lose sight of why alendronate is prescribed in the first place. A New Zealand analysis framed the trade-off in stark terms. For an 80-year-old woman with a previous fracture and very low bone density, the estimated probability of a hip fracture in the next decade is around 45%, and you would only need to treat about 4 or 5 such women with alendronate to prevent one hip fracture. Hip fractures carry roughly a one-in-four chance of death within 12 months and a high likelihood of permanent loss of independence in survivors. By comparison, the estimated number of women you’d need to treat with alendronate to cause one case of ONJ is at least 60,000.¹⁹

That ratio matters. Stopping alendronate out of fear of a rare jaw complication, while leaving osteoporosis untreated, exposes you to a much larger and more immediate danger. The smart approach is not to avoid the drug but to manage the risk: keep your teeth and gums healthy, tell your dentist you’re on a bisphosphonate before any procedure, and discuss timing of elective dental work with both your dentist and prescribing doctor.

Alendronate and Orthodontic Treatment

One less obvious dental complication applies to the small number of adults taking alendronate who also need orthodontic work, like braces. Moving teeth with orthodontic force depends on the same bone remodeling process that alendronate suppresses. Animal research has shown that alendronate dramatically slows tooth movement. In a rat model, teeth in the alendronate group moved less than a quarter of the distance that teeth in the control group did over four weeks.²⁰ While human studies in orthodontic patients specifically are sparse, this finding suggests that adults on alendronate should expect much slower progress with braces or clear aligners and should discuss the medication with their orthodontist before starting treatment.

Newer Osteoporosis Drugs and Jaw Risk

Patients who are worried about jaw complications sometimes ask about switching to a newer osteoporosis drug. Romosozumab, a bone-building antibody approved in recent years, works by a different mechanism than bisphosphonates, stimulating new bone formation rather than simply preventing bone breakdown. Real-world data comparing romosozumab to parathyroid hormone analogs (another class of bone-building drug) found very low rates of ONJ in both groups during the first year, with no detectable difference between them.²¹ The follow-up period was only one year, though, and romosozumab treatment is typically followed by an antiresorptive drug like alendronate to maintain the bone gains. So while romosozumab itself may carry less jaw risk during its short treatment window, most patients end up on a bisphosphonate afterward anyway.

Denosumab, another commonly prescribed alternative, works differently from bisphosphonates but still suppresses bone resorption and carries its own documented ONJ risk. The advantage of denosumab is that its effects wear off within months of stopping, unlike alendronate’s years-long persistence in bone. That reversibility could theoretically make pre-surgical planning easier, though it introduces a different problem: rapid bone loss after discontinuation if a bisphosphonate isn’t started promptly. There is no osteoporosis treatment that eliminates jaw risk entirely while still protecting bones effectively. The practical question isn’t which drug avoids the issue but how to manage oral health proactively while staying on whichever medication your bones need.