0 if cells dedifferentiate, they return to an earlier stage of development in order to grow again: --
But even though some of the limb cells are able to dedifferntiate, they are not able to fully dedifferentiate to the level of multipotent progenitor cells.
Adult cells dedifferentiate (though not fully into embryonic stem cells) into a mass of cells that then re-differentiates into the new structure.
Myoblasts that do not form muscle fibers dedifferentiate back into satellite cells.
In newts, muscle tissue is regenerated from specialized muscle cells that dedifferentiate and forget the type of cell they had been.