ANSWER: Every 3 months

Although this may come as a shock to you; toothbrushes aren’t meant to last a lifetime. With constant use, the bristles become weak and begin to become misshapen. When the bristles start to fry or bend, your toothbrush becomes less effective. A new toothbrush, with more sturdy bristles, removes more plaque than a worn-down toothbrush, studies show.

Any exceptions to this rule?

Something to consider, even if your toothbrush looks clean and your bristles seem sturdy, it contains an excess of bacteria. Especially after recently being sick. Those germs can linger, even after you rinse your toothbrush under the faucet. So, if you do not replace your toothbrush after feeling better, you run the risk of potential reinfection!