Most mammals, such as humans, have only one set of replacement teeth and some mammals, like mice, have only a single set with no replacement. Using sophisticated genetic techniques, researchers activated tooth regeneration in mice, and additional teeth were formed as a consequence.

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Most mammals, such as humans, have only one set of replacement teeth and some mammals, like mice, have only a single set with no replacement. Using sophisticated genetic techniques, researchers activated tooth regeneration in mice, and additional teeth were formed as a consequence.