The experiments helped researchers narrow down possible treatments to the use of proteins that directed stem cells to become bone-forming cells. Those proteins ?called bone morpheonetic proteins ?have already shown promise as a regeneration therapy for craniofacial reconstruction.
"None of us had any idea at the time how or if those proteins could be useful in treating tooth loss," Dr. Wikesjö says.
To find out, researchers placed the proteins around teeth and implants in animal models.
Around teeth, the bone-forming cells grew into existing bone and eventually morphed into bone themselves. However, the root of the tooth was destroyed by the replacement bone. That process impeded regeneration of other essential tissues around the tooth.
Applying the protein to implants proved more beneficial.
"There was almost complete regeneration," he says. "The generated bone bonded with the implant's surface and, eventually, existing bone in the gums. That allowed for the regeneration of gum tissues."
The next step is clinical trials of an implant coated with the proteins, which Dr. Wikesjö hopes to start this summer.
"There are still things we need to learn. In some cases, the protein may rapidly release from the implant, and other times, there appears to be a more gradual release," Dr. Wikesjö says. "We need to find out what factors cause that. In the end, we may not need to use much protein to make the implant effective. Those are things we're looking at now."