A study has found that human wisdom teeth contain a valuable reservoir of tissue that could be used to create stem cells, researchers say.

Research has found that inducing the activity of four genes in adult cells could "reprogram" them into a stem cell-like state; biologically, these induced pluripotent stem, or iPS, cells are virtually identical to embryonic stem cells, opening a potential avenue for stem cell therapy, an article in the Journal of Biological Chemistry said.

But making iPS cells isn't easy and requires a large amount of "starter" cells, which might involve difficult extraction from body tissue (unfortunately skin cells, the easiest to acquire, don't "re-program" well).

Scientists at Japan's National Institute of Advanced Industrial Science and Technology may have found an ideal source: third molars, commonly known as wisdom teeth. The soft pulp inside of teeth contains a population of cells ideal for producing iPS cells, the researchers found.

Wisdom tooth extraction is a common medical procedure in developed nations and creates a perfect opportunity to remove biological material in a sterilized setting; the teeth subsequently can be frozen and stored for many years until needed.