The mouse stem cells, extracted from embryos, were specially raised to be “inducing”—that is, able to instruct other cells to start growing into a tooth. When these inducing stem cells were mixed with cells from human gums, and the combination transplanted into adult mouse kidneys, the result was a tiny tooth-shaped structure with proper enamel and roots. The roots were determined to be viable, meaning that if the tooth were to be implanted in a human jaw it would likely grow into the bone.
The results, published last week in the Journal of Dental Research, pave the way for future experiments using
human stem cells to create new teeth. One challenge is that currently scientists only know how to make embryonic stem cells tooth-inducing, and human embryonic stem cells are fraught with ethical controversy.
Thus an alternative source of stem cells will be necessary for these experiments to go forward. Luckily adult stem cells can be easily obtained from the pulp of wisdom teeth, among other sources. However it’s unclear at this point if adult stem cells can become tooth-inducing.
An outside researcher told the BBC that, while a whole tooth might be a ways off, biologically-grown tooth fillings could be on the horizon in the next 10 to 15 years.
Source: Discover Magazine