You'll generally be told to swap out your electric toothbrush head every three or four months depending on the model you use and the advice provided by your dentist. However, that's only a rough guide. Regardless of how long you've been using the same toothbrush head, there are a few times you should replace immediately, and here are just four.

1. When the Bristles Are Frayed

Probably the easiest way to tell whether your toothbrush needs a change is by looking at the bristles. They should be fairly uniform in orientation, and length should be around what it was when you first starting using that toothbrush head. If the bristles are short or frayed, you need to make a switch. Your toothbrush won't be cleaning your teeth effectively anymore; additionally, frayed or split bristles can damage the teeth and gums.

2. When Colours Are Faded  

Most toothbrushes have coloured bristles, and that's not just for added style. At first, bristles are usually quite dark and vivid. As you use your toothbrush, you'll notice they start to lose colour. Eventually, they will look very faded. This indicates that you need to change the head.

3. When You Notice an Odour 

When you don't take care of your oral health, you'll start to notice your breath growing less pleasant. Proper oral care removes food debris, neutralizes unpleasant acids, and prevents odour-producing bacteria thriving within your mouth. Unfortunately, food debris and bacteria can eventually migrate to your toothbrush. This isn't anything to worry about at first, but it's going to seriously inhibit your ability to keep your teeth clean after a while. This is one of the main reasons why you need to change heads. If you notice that your toothbrush head has developed an unpleasant odour, it's probably due to food debris and bacteria, so switch it out for another.

4. When You've Recently Been Ill

Most signs your toothbrush head needs replacing revolve around the head itself, but not all of them. Even if your toothbrush head looks and smells pristine, you should switch it for a new one if you've just gotten over some kind of illness. Germ can occupy your toothbrush when you're ill, which means you could re-expose yourself or transfer germs to the toothbrushes of other members of your family. This is important for all illnesses, put its particularly importance after mouth sores, throat sores, flu, colds, or tonsillitis.