A team of Japanese scientists may have discovered an ideal source of induced-pluripotent stem cells (iPS), a non-embryonic source of stem cells for future regenerative medical applications.  Hajime Ohgushi, from the National Institute of Advanced Industrial Science and Technology (Japan), and colleagues find that third molars, commonly known as wisdom teeth, are a rich source of mesenchymal stromal cells that are similar to cells found in bone marrow, a common stem-cell source. Collecting tooth samples from three donors, the team successfully generated a series of iPS cell lines by activating three key genes; the different cell lines displayed varying degrees of robustness but in some cases proliferated quite well, up to 100 times more efficiently than typical skin-cell-derived iPS cells. The molar-derived cells also could differentiate into many other cell types including beating cardiomyocytes (heart cells).  Noting that: “Because human third molars are discarded as clinical waste,” the researchers submit that: “our data indicate that clonally expanded [mesenchymal stromal cells] derived from human third molars are a valuable cell source for the generation of [induced-pluripotent stem] cells.”