The government's approval of Periostat will not end the scraping away of hardened plaque that patients now endure, but the pill did significantly improve their gums in tests - and might make dental visits less painful.
"This is a whole new concept" in treating gum disease, said Dr. Sebastian Ciancio, past president of the American Academy of Periodontology, who studied Periostat at the State University of New York at Buffalo. "For the first time, we have a drug that helps the body begin to heal."
Until now, periodontal treatments have focused just on attacking the bacteria that cause gum disease.
But scientists at SUNY's Stony Brook campus accidentally discovered that bacteria are not the whole problem. The mouth reacts to the germs with inflammation that breaks down the gums and eventually the bones that hold teeth in place.
Periostat suppresses the enzyme responsible for that break-down, so the pill - together with scraping away hardened bacteria - helps slow, or perhaps even halt, gum disease.
Finding that enzyme's role "was the eureka discovery," said lead researcher Dr. Lorne Golub. Using Periostat daily, "it looks like we've arrested the disease in cases where patients were told by their dentists that they were probably going to lose their teeth."
$1 to $4 dayManufacturer CollaGenex Pharmaceuticals announced the Food and Drug Administration's approval of Periostat yesterday, saying the pill - available by prescription only - will be on pharmacy shelves within two months. A price has not been set, but a spokeswoman said treatment would cost between $1 and $4 a day.
The American Dental Association greeted the pill "with guarded optimism," said Dr. Dan Myer, its associate scientific director.
Dentists want more detailed studies of the drug's long-term effects, and patients still must properly brush and fight the bacteria that cause gum disease, he stressed. But Periostat "does have the promise of slowing down the disease."
Half of all Americans have gingivitis, a gum inflammation often controlled with proper brushing and flossing. but in at least 20. million Americans, the problem advances to. periodontitis, a serious disease where gums pull. away from the roots of teeth and underlying bone is destroyed.
Scaling and PlaningDentists use special instruments to regularly scrape off plaque, sticky bacteria, that hardens below the gum'’ surface, a painful procedure called "scaling and planing." Dentists also prescribe topical antibiotics. Still, some patients need extensive gum surgery and lose teeth.
Golub discovered that antibiotics sprayed onto the gums of rats both attacked germs and suppressed the enzyme collagenase, the substance that destroys gum tissue. Wondering if that was just an extra effect of antibiotics or clinically important, Golub studied specially bred gem-free rats - so rare they cost $7O each - and found that suppressing collagenase was a new and separate way to attack gum disease.
A weakened form of the antibiotic doxycycline, so weak that it does not attack bacteria but does suppress collagenase, seemed to work best. CollaGenex named the pill Periostat and studied it in 800 patients. In one pivotal study, patients who took Periostat after standard plaque scraping had their gums reattach to teeth 52 percent better than patients who had plaque removal alone. Periostat patients also had 67 percent more improvement in the depth of gum loss.
Study participant Jo Ann Buczkowski of North Tonawanda, N.Y., said that since taking Periostat, her regular plaque scalings are less painful. "I used to do a lot of bleeding before and I get very little bleeding now," she said.
Nobody knows how long patients should take Periostat, something scientists continue to study.
While it's exciting that we have another tool to treat periodontal diseases, it's important to keep this development in proper perspective:
Firstly, realize that this is a very low dose of a common antibiotic (Doxycycline) which researchers chanced upon when treating the infection that underlies periodontal disease. A similar, anti-inflammatory effect is seen with a number of other medicines, Ibuprofen for one.
Periodontal diseases are, for the vast majority of adults, chronic (long-lasting) bacterial infections. One of the ways our body fights infection is by modifying collagen in our gum tissues, dissolving some in one area, and rebuilding it in another. This is a natural process is called remodeling. Periostat would interfere with this process, making collagen fibers throughout our body more resistant to this remodeling process. This may slow the progression of disease, but following issues are left to ponder:
1) Because of the chronic nature of this infection, shouldn't we treat the cause (the bacteria) rather than treat the effect?
2) If we don't remove this infection, doesn't that commit our patients to take this synthetic drug for the rest of their lives (at $1 to $4 a day)?
3) We have ample evidence that low doses of antibiotics often lead to bacterial adaptation and resistance. Is it conceivable that the same process can happen here?
4) What happens when this infection is already at the level of the bone, or lies within the bone itself?
As you can see, we have more questions than answers regarding Periostat. Stay tuned for more developments. . .