Purdue Alumnus

A scientist inspects his equipment and experiment
Tooth Bank

Could saving your dental stem cells be the secret to treating future illness?

Michael Byers thinks so.

The Tooth Bank is asking you to make an investment. 

Forget collecting coins or dollar bills under your pillow when you lose a tooth — that’s all about instant gratification. No, the Tooth Bank focuses on the long term and the dental stem cells attached to your teeth. And the tooth fairy of the 21st century — wearing a surgical mask and scrubs — will visit you years after your tooth is gone to return your healthy dental stem cells to you in your time of need.

“You can bank down some 15-year-old’s dental stem cells that are in their 15-year-old state, and when they are 50–60 years old, and they need the stem cells for some therapy, we’ll have it there for them,” says Michael Byers (S’03), founder, president, and CEO of the Tooth Bank in Brownsburg, Indiana. “It’s really fascinating that you can literally freeze something and years later you can pull it out and it is still alive. It is frozen in the exact state you left it years ago.”

Michael Byers
Photo by Charles JiSchke (MBA’08)

Byers, who majored in biology with a neuroscience concentration, started the Tooth Bank in 2014. The mission was simple: Offer a way for patients to collect and store stem cells collected from their extracted teeth for possible use in the future. That mission is resonating across the country, especially with parents. The Tooth Bank is one of four similar companies operating in the United States and a few others around the world. It currently has about 3,000 customers who pay the annual fee to ensure their stem cells remain available for later use.

In recognition of the future medical possibilities, the American Academy of Pediatric Dentistry adopted a policy regarding dental stem cells. It “encourages dentists to follow future evidence-based literature in order to educate parents about the collection, storage, viability, and use of dental stem cells with respect to autologous regenerative therapies.” Autologous therapies are those where the patient is also the stem cell donor.

Prior to starting Tooth Bank, Byers was vice president of operations at General BioTechnology (GBT), which did a lot of umbilical cord blood banking.

“When I started at GBT, the science of cord blood banking was new. Now it is more advanced and most people have heard about it,” he says. “It’s only a matter of time before dental stem cell banking is at that same level of familiarity.”

Promising research

The outlook for the uses of dental pulp stem cells is promising. Tooth Bank’s parent company, Cryopoint (also founded by Byers), is an active participant in clinical studies to find uses for adult mesenchymal stem cells (MSCs), which are the type of cells found in dental pulp. Byers is particularly excited about research his company is involved in with the Mayo Clinic.

“The MSCs are as close as embryonic stem cells as any cell they’ve tested,” he says. “You can harvest MSCs from fat tissue, bone marrow, placenta, and cord blood tissue. What they’ve found is that dental-derived adult stem cells are earlier stage than most of those from other sources. Because of that, they have the ability to develop into any cell type you need. Cord blood is far enough down the line so they can only be used for blood or immunity-related cells.” The Mayo Clinic study is aimed at developing a therapy that spurs bone development or growth. 

A study published in the Journal of Tissue Engineering and Regenerative Medicine in 2010 supported the possibility of using dental pulp stem cells for regenerating bone. One of the co-authors of the study was Daniel Alge (PhD BM’10), assistant professor of biomedical engineering at Texas A&M University.

“Anybody who has ever had broken a bone knows that it can heal, but in certain instances it needs help, such as with a traumatic injury,” Alge says. “There has been long-standing interest in using stem cell therapy combined with growth factors to regenerate bone for these types of cases.”

The study found dental pulp stem cells grew faster than bone marrow stem cells, and they have a higher percentage of cells that can be targeted to grow into bone and other connective tissues.

“If you are going to use an adult stem cell therapy like this for tissue regeneration, you are going to need a very large number of cells — several millions of them,” Alge says. “The way you get those is you take a tissue sample from patient and then grow the cells in a lab. How fast the stem cells grow will be one of the factors that determine their utility, and our study suggests that dental pulp stem cells may have an advantage here.”

a scientist at work
Photos by Charles JiSchke (MBA’08)

Thousands of other studies and trials around the world have been undertaken to understand how stem cells can be used in medical therapies. Researchers are trying to regrow teeth, regenerate nerves and cartilage, grow bones, improve blood flow, treat diabetes, and assist with liver therapies.

The IOSR Journal of Dental and Medical Sciences highlights two recent breakthroughs with dental stem cells that point to additional success. In 2009, Italian scientists used a patient’s own dental stem cells to repair jawbone defects. And a 2013 study showed dental stem cells can create cells that produce insulin, which would be a boon for people with Type 1 diabetes.

Storing for the long term

The Tooth Bank’s dental pulp stem cell samples are stored in a concrete facility in Brownsburg, Indiana, that now serves as Cryopoint’s headquarters. Teeth waiting to be processed are delivered daily by FedEx in cold-packed boxes. Lab technicians take the teeth to a laboratory and clean rooms to remove the dental pulp from the teeth and prepare it for freezing. If there are multiple teeth, the resulting stem cells are divided and then stored in separate facilities to reduce the risk of fire or other anomalies wiping out a person’s stored stem cells. 

Each sample is placed in a narrow, inch-long vial for storage. The new additions are taken to the storage area, where they are cataloged and verified by a second employee. Finally, they are lowered into a large metal tank where they will be frozen to -196 degrees Celsius until needed by their former host. 

a scientist inspects a cryogenic tank
More than 3,000 dental pulp stem cell samples are stored at -196 degrees Celsius in a concrete facility in Brownsburg, Indiana, that now serves as Cryopoint’s headquarters.  Photo by Charles JiSchke (MBA’08)

Before the Tooth Bank’s 2014 start, Cryopoint was building its reputation as a storage facility for hospitals and fertility clinics. Most hospitals aren’t able to dedicate the necessary space to storing tissue, organs, and other biological materials, so they contract with Cryopoint to do so. Fertility clinics use the same service for long-term storage until they are able to help a couple have a child. This portion of the business serves 50,000 clients. In 2015, the company purchased Cryocyte, whose main focus was storing umbilical cord blood. That storage facility is in Sandy Park, Utah. The Brownsburg facility processes some of the cord blood before it is shipped to Utah. Likewise, the extra dental pulp stem cells divided at the time of processing are stored at the Sandy Park facility. 

Making a Tooth Bank deposit

The Tooth Bank has formed partnerships with thousands of dental offices across the country. Those partner offices keep collection kits on hand for their patients who have wisdom teeth pulled or who want to remove baby teeth before they are pushed out naturally. First and second premolars are also prime candidates for collecting dental pulp. A collection kit consists of a small container with antibiotic and extender solutions, an insulated pouch and a cold pack. The extracted tooth or teeth are placed in the container for overnight delivery to Brownsburg, though the cells can survive in the kit for up to 72 hours. Indianapolis-area patients have their cells couriered to the storage facility.

“There’s usually one to four teeth in a kit. I’ve seen up to 10 — poor kid!” Byers says. “The antibiotic and extender solutions were initially developed for athletic trainers who had to treat athletes when a tooth was knocked out. The same technology works great for our purposes.”

Extracting and saving your own dental stem cells is attractive because you don’t have to worry about your body rejecting them when they are reintroduced. A transplant patient has to be a human leukocyte antigen (HLA) match with the donor; if not, the immune system will reject the transplant, causing graft versus host disease. With one’s own stem cells, there is no worry about a mismatch.

Matt Bojrab, an oral and maxillofacial surgeon in Fishers, Indiana, is a medical advisor for the Tooth Bank, and he recommends the service to all of his patients. On any given day, he extracts 20 to 40 teeth from his patients, and those teeth — especially wisdom teeth — contain as many as 2 million stem cells each. Bojrab is looking forward to the day — in maybe seven to 10 years — when stem cell science will help him to heal bone defects in trauma and reconstructive surgery patients.

“If we can inject a substance in and have the bone heal faster or regenerate bone defects, that will be fantastic,” Bojrab says.

When they can, Cryopoint also helps supply dental stem cells for active research projects. When doctors and research scientists want to conduct a study, Byers works with his dental partners, such as Bojrab, to collect additional dental stem cells through voluntary donations. Cryopoint ensures the cells are sterilized without being damaged, and they culture cells to make sure the amount of cells is sufficient for the study.

“As storage partners, we can supply everything necessary for research studies and collaborations. We’ve provided tissue samples and full-size organs, such as livers, hearts, and lungs,” Byers says. “For instance, one of our clients used amniotic membrane for a soldier’s skin regeneration.”

Peace of mind

While the scientific possibilities are fascinating, the storage of dental stem cells mostly comes down to peace of mind. 

And the constant innovation and creativity in research studies continues to provide hope to many.

Both Bojrab and Byers plan to bank their children’s dental stem cells. Bojrab, especially, believes it will provide an extra layer of insurance for his two children because they are adopted. He knows some of their medical history, but having the dental stem cells available, he believes, offers additional peace of mind that future unknown medical issues may be treatable.

“Basically, this is a form of insurance for their children,” Byers says of a majority of his clients. And the testimonials parents have given to the Tooth Bank ask simply, “Why wouldn’t you do this for your kids?” As more research is published, clinical trials are conducted, and stem cell therapies are approved by the Food and Drug Administration, more and more parents will likely be asking the same question.

Steven Lincoln is a freelance writer.