If your mouthguard falls out when you open your mouth, feels loose during sport or only stays in place when you're biting down, there's a good chance it isn't fitted correctly.
Fortunately, many fitting problems are easy to fix. This guide explains how a mouthguard should fit, how to check yours and what to do if something doesn't feel right.
If you haven't fitted your OPRO mouthguard yet, follow our step-by-step guide before using the advice below.
How Should a Mouthguard Fit?
Every mouthguard should fit snugly around your upper teeth without needing to be held in place by biting down.
A correctly fitted mouthguard should:
- Stay securely in place when you open your mouth.
- Feel snug but not painfully tight.
- Allow you to breathe comfortably.
- Let you speak clearly, even if your voice sounds slightly different.
- Cover your upper teeth evenly.
- Feel comfortable against your gums without rubbing or creating pressure points.
A properly fitted mouthguard should become something you barely notice during training or competition. If you constantly adjust it or bite down to stop it moving, check the fit.
How to Tell if Your Mouthguard Fits Properly
Once you've fitted your mouthguard, you can carry out a few simple checks before wearing it for sport.
The Drop Test
Open your mouth and relax your jaw.
A properly fitted mouthguard should stay securely in place without dropping down or falling out.
The Talk Test
Try having a normal conversation or read a few sentences aloud.
You should still be able to communicate clearly with teammates and coaches.
The Breathing Test
Take several deep breaths through your mouth.
Your mouthguard shouldn't make breathing feel restricted or uncomfortable.
The Comfort Test
Wear your mouthguard for five to ten minutes.
It should feel secure and comfortable without causing sore spots, rubbing against your gums or making you gag.
If your mouthguard doesn't pass these checks, don't worry. Most fitting issues have simple solutions.
Why Won't My Mouthguard Stay In?
One common question we hear is why a mouthguard falls out or only stays in place when you bite down.
Usually, the problem isn't the mouthguard itself. It's the fit.
Common reasons include:
- The mouthguard wasn't softened for the correct amount of time.
- It wasn't centred over your teeth before biting down.
- Firm, even pressure wasn't maintained during fitting.
- The mouthguard cooled too much before being fitted.
- The wrong size or style has been selected.
- Your teeth have changed since it was originally fitted.
If your mouthguard feels loose, the first step is usually to remould it, following the fitting instructions carefully.
A correctly fitted mouthguard should grip your upper teeth naturally. You should not need to clench your jaw to keep it in place.
If you've followed the fitting instructions more than once and the fit still isn't right, our customer care team can help through the OPRO Precision Fit Guarantee.
Why Does My Child's Mouthguard Keep Falling Out?
Children's mouths constantly change, which can affect how a mouthguard fits.
A mouthguard that fitted perfectly at the start of the season may become loose as adult teeth come through or the jaw develops.
If your child's mouthguard keeps falling out:
- Check that you've chosen the correct size.
- Remould the mouthguard following the instructions carefully.
- Make sure it sits centrally over the upper teeth.
- Ask your child whether it feels loose, uncomfortable or makes them gag.
A child should never have to bite continuously to keep their mouthguard in place.
If the fit still isn't right after remoulding, it may be time to choose a different size or replace the mouthguard.
Common Mouthguard Fitting Problems
My mouthguard feels loose.
Remould it, following the recommended timings and biting firmly for the full fitting period.
My mouthguard hurts my gums.
A properly fitted mouthguard should feel snug, not painful. Sharp pressure points usually indicate that the mouthguard hasn't moulded evenly.
My mouthguard makes me gag.
This may be caused by an incorrect fit or a wrongly positioned mouthguard during fitting. Check that it is centred correctly before considering a replacement.
My mouthguard moves when I talk.
Some changes in speech are normal. However, the mouthguard should not slide inside your mouth while you speak.
When Should You Replace Your Mouthguard?
Not every fitting problem means you need a new mouthguard.
If your mouthguard has become loose, remoulding it may restore a secure fit. However, if it is damaged, worn out, or no longer fits because your teeth have changed, it may be time to replace it.
Read our guide to Signs It's Time to Replace Your Child's Mouthguard to learn when a mouthguard should be replaced and the warning signs to look out for.
Frequently Asked Questions
Should a mouthguard stay in without biting?
Yes. A properly fitted mouthguard should stay securely in place without you needing to bite down or clench your jaw.
Why does my mouthguard keep falling out?
This usually happens because it hasn't moulded closely enough around your teeth, wasn't fitted correctly or is no longer the right fit for your mouth.
Can my child outgrow a mouthguard?
Yes. As children's teeth and jaws develop, the fit can change. Check it regularly throughout the year, especially after new teeth come through.
Can I remould my OPRO mouthguard?
Yes. OPRO mouthguards are remouldable, letting you repeat the fitting process if you are not happy with the initial fit. Follow the fitting instructions carefully and avoid overheating the mouthguard.
When should I contact OPRO?
If you've followed the fitting instructions carefully, remoulded your mouthguard and you're still unable to achieve a secure fit, our customer care team will be happy to help through the OPRO Precision Fit Guarantee.
