You should change your toothbrush every 3 to 4 months, or sooner if the bristles become frayed or worn. Over time, bristles lose their effectiveness at cleaning your teeth, and a worn toothbrush can’t do its job properly. Additionally, bacteria and debris can accumulate on the bristles, so replacing your toothbrush regularly helps maintain good oral hygiene.
If you’ve been sick (e.g., with a cold, flu, or strep throat), it’s a good idea to replace your toothbrush afterward to avoid reintroducing germs into your mouth. For electric toothbrushes, replace the brush head on the same schedule.