Researchers have developed a way to grow human-sized tooth-like tissues in the mouths of pigs – this may be a lot to chew on, but the results could lead to new biological tooth substitutes that can be used to replace existing synthetic implants.
The idea of growing human-like teeth in another animal’s mouth may sound distinctly unappealing for many reasons, but recent developments in tissue engineering have begun to offer new options for medical interventions in the future. In a new study, scientists from Tufts University of Dental Medicine in Boston, grew a combination of pig and human tooth cells in pieces of pig teeth to create human-like teeth in the animal’s mouth.
They achieved this by taking cells from human dental pulp and mixing them with cells from pigs’ tooth buds. As MIT Technology Review discusses, the researchers harvest cells from pig jaws that they get from slaughterhouses, then grow them in the lab. This cellular mixture was then seeded onto a tooth-shaped “scaffold” made of pig teeth that had been stripped of cells, leaving just the extracellular matrix.
After this, the not-quite teeth were grown in a bioreactor for a week before being implanted in the jaws of several living pigs. After 2 or 4 months, the implants were harvested, and it was observed that pigs had grown tooth-like tissue. Photos of the animal’s mouths show their usual larger, sharper, tusk-like canines next to smaller, more human-like tooth structures. When removed, the team found that these proto-human-like teeth had developed hard layers of cementum and dentin.
The results represent a significant step towards the development of alternative lab-grown, living human teeth that can be integrated into a person’s gums. This could lead to viable living alternatives to the synthetic options available today.
The use of titanium implants to replace missing teeth has become increasingly widespread due to their reported success (~10 years) and highly lucrative clinical market.”, the team writes in their paper. “The global dental implant market is […] valued at USD 6.6 billion in 2023 and was predicted a compound annual growth rate of 9.6% to reach a USD 10.53 billion market in 2029.”
However, these replacement teeth are expensive and do not last forever, which means people will have to replace them. “It is therefore essential to devise effective alternative tooth replacement therapies to ensure healthy long-term patient outcomes, and to avoid a dental healthcare crisis,” the team writes. “We propose that one reasonable approach is to create functional, bioengineered living teeth, complete with functional bioengineered [periodontal ligament] tissues.”
The new pig tooth alternatives could offer a way around the issues facing existing tooth replacement options, but the technique won’t likely be available any time soon. Firstly, the pig-grown teeth did not reach a size that was comparable with a human adult tooth. There is also a significant difference between developing tooth-like structures in a pig’s jaw and transferring the technique to a human subject.
Nevertheless, the results clearly demonstrate the potential for using biologically grown teeth for human dentistry in the future.
The paper is published in the journal Stem Cells Translational Medicine.
