Every 3 months.
This is how often you should replace your electric toothbrush head. It is also the same time period that you should replace or change your manual toothbrush.
You should replace the toothbrush or the brush head sooner if the bristles of the head are clearly worn, frayed or damaged in any way. Using for longer can potentially be damaging to your teeth and gums.
Video
Our in-house dentist Dr. Chhaya Chauhan runs through this advice in the video below.
Advice from dental organisations and studies
The advice from the Australian Dental Association is to replace your toothbrush every 3-4 months.
The NHS in the UK and the Oral Health Foundation suggest 3 months.
A study in Korea investigated levels of different types of bacteria found on toothbrushes. The authors found that after three months the bacterial levels more than doubled compared to a toothbrush which had been used for one month. Some studies actually argue for replacing your toothbrush every 1-2 months because of this.
Although there is a slight difference in time frame, you can see that there is a similarity in the answers.
It is generally agreed that you should replace your toothbrush at around 3 months.
As long as the brush head is in good condition, if you use it for a week or two longer, it’s not a big issue.
If the brush head is clearly worn, frayed or damaged you should replace it as soon as possible.
Toothbrush bristles wear and degrade
The brush head on a manual or electric toothbrush is formed of hundreds of bristles that are clustered together.
Some bristles may be shorter, some may be longer, some may be angled and some may come in a variety of colours.
The nylon bristles are designed to be repeatedly used and their construction can withstand thousands of repeated movements. However, there comes a time that those bristles fray, split or are no longer in the tight formation that they once were.
Think of the toothbrush a little like a tyre on a car. After x thousand miles they need replacing because the rubber has worn as a result of the contact with the road. They are less grippy and pose a risk to your safety if you continue to use them.
Or perhaps like your favourite piece of clothing. You will keep wearing it, but at some point it becomes so worn and aged that it needs to be replaced.
The toothbrush or the brush head for your electric toothbrush is no different.
However, it is not a case of waiting until the brush head looks worn out, the wear on the bristles is not always noticeable.
But, if the bristles are clearly worn or deformed sooner than 3 months, replace the toothbrush or brush head.
Under most circumstances the bristles of the toothbrush will normally hold their shape fairly well up to around this 3 month time period.
However, extended use will mean that the formation of the bristles are more likely to suffer as a result.
Take a look at the bristles on your toothbrush. Ask yourself, do they still fairly uniform in their direction and look?
Does the bristle layout look similar to when the brush head was new?
If bristles are shorter, frayed or all over the place then it is time to change.
The images above and below clearly demonstrate damaged and worn bristles. If you brush looks like this, replace it.
Brushing with too much pressure is often a cause of wearing out brush heads quicker than normal.
Remember, the bristles need only skim the surface of your teeth. You don’t need to scrub with a brush. Less pressure is more effective.
If you wear braces, these can cause the bristles to wear or become damaged more easily also.
Damaged, frayed or split bristles can actually do more damage to the teeth and gums. When damaged or misshaped, the toothbrush will not be as effective when used.
Some toothbrushes tell you when to change brush heads
So you know now that the recommendation is to replace your toothbrush or brush head (in the case of an electric toothbrush), every 3 months.
However, trying to remember when you last changed your brush head can be difficult.
Ideally, you would mark it on the calendar or set a reminder when it is time to change, but not many of us will do that.
Many toothbrushes, both manual and electric now help you out.
On any Oral-B, Sonicare and Colgate toothbrush heads there are so-called indicator bristles.
The colour of the bristles start off fuller and darker, but as time passes they become lighter and appear more worn.
More often than not, these bristles are blue in colour and fade to white/clear. It is this fade in colour that acts as a guide to tell you to change brush heads.
You do not have to see both discoloured bristles and frayed or split bristles to change the brush head, in many cases the bristles will still be in formation and just the colour had faded.
If you have a smart electric toothbrush, such as the Oral-B Genius AI or the Sonicare ExpertClean, the smartphone apps can provide reminders on when to change.
Or some toothbrushes from Sonicare, such as the ProtectiveClean series offer BrushSync technology, which actually track your brush head usage via a microchip built into the brush head. When it is time to replace it, a yellow light will show on the brush handle.
See our guides on replacement electric toothbrush heads
Braun Oral-B, Philips Sonicare and Colgate are the 3 major brands manufacturing electric toothbrushes.
Whilst the brush heads are not interchangeable from 1 brand to another, any brush head made by Philips will fit on any Sonicare electric toothbrush handle. It is the same situation for Oral-B and Colgate.
All 3 brands make a variety of different brush heads. Although similar, there are subtle differences that set each of them apart.
If you are unsure as to which brush head you need for your electric toothbrush, I strongly recommend you check out the brush head guides I have created.
