Dentist reveals important reason why you must replace your toothbrush every three months

If you were laying awake at night wondering just how often you should be changing your toothbrush, a good night's sleep might be on the horizon as an expert has weighed in on the question.

There are plenty of life's little details that we don't tend to as often as we should. Whether it's the frequency of which we change our bed sheets, the batteries in the smoke detector or the filter in our coffee makers, it wouldn't hurt if we all paid slightly more attention to things that keep us clean and healthy.

And one of those little details that I'm sure we're all guilty of ignoring is how often we change our toothbrushes - or our toothbrush heads if you're fancy and have an electric one.

Even though we brush our teeth every day, twice a day (if you're not you should be), it can be easy to forget that the key to good oral hygiene is as much about the toothbrush we use as it is the toothpaste that helps us achieve that white, winning smile.

Be honest, when was the last time you changed yours? (Daniel Day / Getty)

So, to keep that smile as attractive and healthy as it can possibly be, dentistry expert Dr Joshua Perlman told the Daily Mail that we should all be swapping out our toothbrushes at least every three months.

Sounds pretty fair, if you ask me.

As much as the 'why' seems pretty self-explanatory, according to the expert, it's a little more complicated than it just being dirty.

As you can imagine, having to do something twice a day every day can be a tiring task, and it's the same for your toothbrush. The expert explains that your bristles can essentially become overworked after three months, and since its purpose is to clean the plaque, food and bacteria from your gnashers, they need to be on top form.

He said: "When toothbrush bristles are overused they can become weakened or frayed.

"When toothbrush bristles become frayed they lose their ability to clean teeth."

And if you're a bit of an aggressive brusher and you see the bristles of your toothbrush getting into a state before three months, go ahead and change it anyway, otherwise you could be on a one way train to cavities and gum disease - and no one wants that.

Time for a new toothbrush? (Daniel Day / Getty)

"This is because the bristles are less effective than new toothbrush bristles that stand straight up and down," Dr Perlman explained.

"Frayed bristles cannot clean into tight spaces between teeth therefore plaque and food debris is often left behind."

Adding that the longer you use your brush the more bacteria it accumulates, Dr Perlman revealed other instances where a change is needed - when your toothbrush starts to smell or change color, or when you get sick.

So, time for a new toothbrush, I think.