Health & Medicine

Pulled teeth are now seen as a source of stem cells

Raul Estrada, 6, of Hialeah, Fla., showed off two permanent teeth growing in where two loose baby teeth were surgically removed for stem-cell harvesting.
Raul Estrada, 6, of Hialeah, Fla., showed off two permanent teeth growing in where two loose baby teeth were surgically removed for stem-cell harvesting. MCT

MIAMI — Naidelys Montoya didn't wait for her son's baby teeth to fall out. She took the boy to an oral surgeon to have two of the loose ones extracted.

"He was a bit scared," said Montoya, of Hialeah, Fla. "He's not that brave."

The dentist shipped the teeth in a temperature-controlled steel container to a lab in Massachusetts, where their stem cells will be spun out, frozen to colder than minus-100 degrees and stored — in case her son, Raul Estrada, 6, might need them to treat a future illness.

Montoya and her son have joined a major new medical movement.

In South Florida and around the world, dentists are extracting baby teeth, wisdom teeth and even healthy adult teeth, and researchers are spinning out stem cells that they think can be used to regrow lost teeth, and someday even repair damaged bones, hearts, pancreases, muscles and brains.

It could put the Tooth Fairy out of business.

"These are teeth we've been discarding as dental waste," said Dr. Jeffrey Blum, the Miami Beach oral surgeon who pulled Raul's teeth. "We might as well get some use out of them."

"I can't help but feel excitement for their potential use in regenerating different tissues in the human body," said Dr. Jeremy Mao, director of the Regenerative Medicine Laboratory at Columbia University. Mao also is chief science advisor to StemSave, a New York City company that freezes the stem cells and stores them for later use.

There are concerns. It's expensive: $590 up front plus $100 a year to store the stem cells of as many as four teeth for as long as 20 years. It's also speculative: The first FDA-approved practical use of such stem cells is years away.

"Every treatment using dental stem cells is still in the clinical testing phase, and won't be ready for general use for at least five years," said Art Greco, StemSave's chief executive.

Other researchers welcome the new source of stem cells.

"Within human adults and children, there are lots of reservoirs of stem cells," said Dr. Joshua Hare, director of the Interdisciplinary Stem Cell Institute at the University of Miami Medical School. He is not involved with dental stem cells. "We get them from bone marrow; others use umbilical cord blood. It seems teeth are also a good source."

The National Institutes of Health concluded in 2003 that teeth are a rich source of stem cells. Every child has about 20 baby teeth that fall out between ages 6 and 12. Adolescents have wisdom teeth that often are removed between ages 14 and 25 because they crowd the jaw or grow in crookedly.

To retain viable stem cells, oral surgeons must extract baby teeth before they fall out naturally, so they have a blood supply to keep them healthy. Blum puts them in a temperature-controlled steel container and ships them overnight to StemSave.

Stem cells are the body's repair system. Stem cells beneath the skin are constantly spinning off new skin cells to replace skin that is sloughed off or damaged in daily life. The same is true for hearts, livers, pancreases — except that as the body weakens from age, injury or disease, those stem cells start to lose the ability to keep up, and they need help. Today, stem cells from bone marrow, blood and now perhaps teeth can be reprogrammed to help those ailing organs.

Also, by using these stem cells, researchers avoid involving human embryonic stem cells, which are controversial because their creation involves destroying human embryos.

The first practical use of dental stem cells probably will be to repair human teeth and jawbones, researchers say. At Boston University's School of Dental Medicine, researchers have used stem cells from baby and wisdom teeth to generate dental pulp, the soft interior of a tooth, and dentin, its hard white casing.

They are inserting the material into a broken human tooth and implanting it into a mouse to tap a blood supply. When the technology reaches humans, the pulp material would be injected into a spongy "scaffold" where a tooth has been removed to prompt it to grow into a human tooth. It's at least five years away.

The use of stem cells to heal the human body is exploding. At the University of Miami's medical school, Hare is conducting human trials using stem cells from bone marrow to inject around damaged hearts, hoping to regenerate damaged heart tissue.

Stem cells from umbilical cord blood have saved the lives of patients with leukemia, lymphoma, multiple myeloma, aplastic anemia, sickle cell and other diseases.

So far, only private banks are storing dental stem cells, although Mao says a public bank would be valuable and appropriate.

The American Dental Association, while cautiously optimistic about the potential of dental stem cells, urges parents to consider both the cost and the rarity of use before joining private donation programs.