Polymer Fills a Major Gap in Dentistry

Americans lose 30 million teeth every year to periodontal disease.

In this process, plaque fosters bacteria that eats away gums, exposing the hard tissue of the jaws. The bone in the jaws then decays and recedes, eventually allowing the tooth to work loose.

But some dentists are hopeful that a new material known as HTR polymer can stop this process. They are gritting their patients’ teeth, so to speak, and it seems to work.

For the past nine years, several periodontists on the East Coast have been packing HTR polymer into the gaps that occur between teeth and diseased jaws. It appears they are growing bones and saving teeth.

‘Very Happy With It’

The polymer, essentially tiny porous plastic beads coated with a calcium compound, also appears useful for bolstering jaw ridges as denture anchors and preventing jaw deterioration where a tooth has been removed.

“I’m very happy with it,” says Dr. Virginia Murray, a New York periodontist.

“We’ve tried all sorts of fillers--human bones, animal bones, plaster of Paris,” she says. “But none of them have worked as consistently, or as well, as this.”

The new material’s manufacturer, U.S. Surgical Corp. of Norwalk, Conn., claims the product could save a lot of teeth. Perhaps not 30 million, but “millions and millions,” says John Hiltunen, a company spokesman.

Some Still Skeptical

But some experts in the field are skeptical about HTR, as they were about various ceramics and metal pins that preceded it.

“The jury is out,” says Dr. Pui L. Fan, of the American Dental Assn.’s council on materials and instruments. “No material has been actually proven to stimulate bone growth.”

Fan will not say that HTR does not work, or will not work, only that “I need to see the data.”

A recent company-backed survey of 64 dentists, periodontists and oral surgeons found that in 647 uses of the material, 634 were considered a success. All of the failures occurred in trying to save teeth loosened by periodontal disease.

Success Rate 98%

Before receiving Food and Drug Administration approval in 1983, HTR was used experimentally in just a few clinics in New York and the surrounding area. But since then, the material has achieved a 98% success rate in more than 4,000 uses worldwide, the company claims.

However, these results and the material itself have not been submitted to the dental association, which therefore has no official position on the product.

Nevertheless, the company is hoping the material will gain acceptance nationwide, and recently made a big publicity push at the Midwest winter dental meetings in Chicago.

Dentists at the meeting appeared to range from jaded to interested to excited, but none were nearly as enthusiastic as Dr. Arthur Ashman, the New York city dentist who invented the stuff.

‘Ideal Grafting Material’

“Biologically compatible, non-reabsorbable, hydrophilic (capable of taking up water) and negatively charged,” Ashman says. “What I’m describing for you is the ideal grafting material, which also happens to be HTR.”

Ashman describes the way HTR works as both mysterious and simple. The small granules, which are injected in the corroded space around the tooth, act as “a sort of scaffolding” around which new bone material can collect and grow.

The material’s hydrophilic (“water-loving”) nature attracts wet bone marrow cells, and the negative charge holds them there and stimulates growth. The calcium allows the material to integrate with the bone.

Other Uses Seen

Ashman, once the head of dental research at Mt. Sinai School of Medicine in New York, is no longer willing to stop with teeth. HTR stands for hard tissue replacement, and Ashman believes wherever there is need for that, HTR should work.

“We’ve already done a considerable amount of work on the spinal fusion and in the treatment of bone fractures,” he says. “And I think there will be all sorts of uses in reconstructive surgery, plumping up chins and cheeks.”

Molded, Ashman says HTR could even prove effective as a complete bone replacement. “Basically, I think we may see the day when we’ll be able to use molded pieces of this material to replace bone that’s been lost because of trauma, disease or cancer.”

Having said all that, Ashman adds, “That’s the theory anyway.”