Why do I keep getting a sore throat after wearing my nightguard?

What's actually causing the irritation

Most nightguards are moulded to cover the back teeth, and if the edge extends even a millimetre too far towards the throat, it sits against soft tissue that was never designed to touch hard acrylic for eight hours straight. That tissue gets irritated the same way a rubbing shoe irritates your heel. You wake up with a scratchy, raw feeling that can last most of the morning.

A second, very common cause is mouth breathing. A bulky or poorly fitted guard can make it harder to keep your lips sealed, so you end up breathing through an open mouth all night. That dries the throat lining out completely, and a dry throat feels sore in exactly the way you're describing, especially the first hour after waking.

There's also a muscular explanation that people don't expect. The muscles used for clenching and grinding, particularly the ones near the jaw joint and side of the neck, can refer pain upward into the throat area. If your guard is actually working and reducing grinding, the muscles sometimes tighten differently overnight as they adjust, and that tension can feel like throat soreness rather than jaw soreness.

How to tell which one it is

A fit problem usually comes with a specific sore spot you can point to, often on one side, sometimes with a small ulcer or red patch where the guard edge sits. A dry mouth problem feels more like a general scratchy throat that eases within half an hour of drinking water. Muscle referral tends to come with some jaw tightness or a dull ache near the ear as well, not just the throat on its own.

It's also worth thinking about timing. If the soreness started the night you first wore the guard, it's almost certainly fit. If it developed gradually over a few weeks, the acrylic may have worn or warped slightly, which happens with boil-and-bite or older guards more than with lab-made ones.

None of this is something to self-diagnose with certainty. A dentist can tell within a couple of minutes of looking at the guard in your mouth whether it's a fit issue, by checking the posterior border and how far back it extends relative to where your soft palate starts.

What to do next

If the soreness is mild and clears within thirty minutes of waking, try sipping water before bed and right after you take the guard out, and see if that resolves it on its own over a week. If it doesn't, or if you notice ulcers, a change in your snoring, or you wake up gasping, stop relying on home fixes and get the guard assessed properly.

At The Dentist in Al Qusais, Dr. Faris Alkhanafseh and Dr. Mohammad Nour both check nightguard fit as part of general dentistry appointments, adjusting the acrylic edges or remaking the guard if the border is sitting where it shouldn't. New patients get a free first checkup, so there's no cost barrier to having this looked at before the irritation becomes a habit you just tolerate. Book through WhatsApp or thedentist.ae/book and bring the guard with you so it can be checked while it's actually in your mouth.