Drugs used to fight cancer and osteoporosis can create ‘dental cripples’

-The Kansas City Star

02/03/2009- Geneva Grimpo fell and broke her hand and arm, doctors put the tiny, fragile-looking woman on drugs to strengthen her bones.

Three years into her drug therapy, trouble began.

Her lower jawbone poked out through sores on the left side of her mouth where her gums had decayed. The visible bone was dead, and she used her fingers to fish out tiny bits as they broke off.

“Now my right jaw hurts,” said Grimpo, 85. X-rays show that bone is dying, too.

Her problem is a growing concern for dentists nationwide. It is called osteonecrosis of the jaw, or ONJ, a condition in which the gums become painful and infected, exposing underlying areas of dead bone in the jaw.

Dentists see ONJ in patients who take certain bone-strengthening drugs used to fight cancer or osteoporosis — drugs that include Fosamax, Boniva and Actonel, some of the most-prescribed medications on the market.

In severe cases of ONJ, the infections lead to chronic pain. Decaying bone gives off a foul odor. Eating is difficult.

Even with regular treatment, these oral wounds can take up to two years to heal.

In 2003, medical reports began linking ONJ to a class of drugs called bisphosphonates. Soon after, the Food and Drug Administration required drug manufacturers to include an advisory about ONJ in their product labels.

The earliest cases of ONJ were found among cancer patients who took large intravenous doses of the drugs to keep their cancers from spreading to their bones.

Up to 10 percent of cancer patients taking bisphosphonates may develop ONJ, according to one estimate.

But ONJ also is showing up in otherwise healthy patients, like Grimpo, who take bisphosphonate pills when osteoporosis weakens their bones.

Doctors and dentists had assumed that ONJ among osteoporosis patients was exceedingly rare — about 0.7 cases per 100,000 Fosamax users, according to one widely cited estimate from an American Dental Association panel.

But new research suggests that ONJ, while still uncommon, might afflict more osteoporosis patients. The specialists on the front lines who treat ONJ say they are seeing far more patients than past estimates predicted.

“I’ve had an explosion of patients,” said Brett Ferguson, the chairman of oral surgery at the University of Missouri-Kansas City schools of medicine and dentistry. “No dentist in private practice wants to deal with this. It’s a nightmare for them. They didn’t learn about it in dental school.”

Ferguson sees ONJ patients from throughout Missouri, Kansas and Arkansas. They began arriving at his Truman Medical Center clinic a few years ago. So far, he has seen more than 45 cases. While most are cancer patients, about one in five took oral bisphosphonates for osteoporosis.

“They all say, ‘Why me?’ ” Ferguson said.

Treatment can involve surgery to remove the exposed dead bone, long-term antibiotics, regular use of a prescription-strength antiseptic mouth rinse and scrupulous oral hygiene.

One of Ferguson’s ONJ cancer patients, a woman in her 70s, developed the condition after a dentist routinely extracted the teeth in her lower jaw. A month later, her gums separated from her jaw.

“Each place that got (extracted) would not heal,” Ferguson said. “You could look in her mouth and see her jawbone, her dead jawbone.”

Ultimately the woman had to be fed through a tube.

Another of Ferguson’s patients, a woman who took bisphosphonates for osteoporosis, lost the bone of three tooth sockets in a row in her upper jaw, exposing her sinus cavity.