Unlikely source of new teeth from human urine

Posted Jul 30, 2013 by Kathleen Blanchard
Replacing our teeth might come from an unlikely source in the future. Chinese researchers have found a way to grow new teeth from urine.
The study, published in the journal Cell Regeneration means someday we might be asked to provide a urine specimen at the dental office in anticipation of a new set of teeth.
The study authors write: "Teeth are vital not only for a good smile, but also good health. Yet, we lose teeth regularly due to accidents or diseases. An ideal solution to this problem is to regenerate teeth with patients' own cells."
In this case the cells for new teeth would come from a person's own stem cells in the urine, rather than using acrylic or metal.
Scientists know from past studies that urine can be a viable source of stem cells that can be coaxed into producing a variety of cell types, including liver, heart and other types of cells that grow to help repair or replace damaged organs and tissue.
Duanqing Pei and his colleagues from Guangzhou Institutes of Biomedicine and Health, and other Chinese universities have now found a way to grow teeth from urea that mimic natural tooth development.
The researchers use two different types of cells - one that grows enamel and another that produces mesenchymal cells to grow dentin, cementum and pulp.
The scientists induced induced pluripotent stem cells (iPSCs) with chemicals to grow epithelial cells in flat sheets and then mixed the cells with embryonic mesenchymal cells from mice. Next they transplanted them into the mice.
Three weeks later the mice were growing teeth that had the same characteristics of normal teeth, but softer.
But the scientists say by substituting human mesenchymal cells for mouse cells and with some other fine-tuning, it would be possible to grow tooth buds in a jar for transplantation in humans. The result would be a fully functional human tooth.
Using urine stem cells to grow new teeth was successful 30 percent of the time in the mouse studies. The Chinese researchers say a bit of tweaking would make it possible to grow and transplant perfectly good teeth for humans.