Mouthguards Making You Sick: Sores, Thrush, and More

Waking up with a sore throat, white patches in your mouth, or painful gum spots can be unsettling, especially if you sleep with a mouthguard every night. It is easy to blame the device. But in most cases, the mouthguard itself is not the real problem; hygiene is.

A dirty, poorly cleaned mouthguard can quietly turn into a breeding ground for bacteria, fungi, and odor-causing microbes. Over time, that buildup can irritate your mouth and throat, triggering symptoms that feel far more serious than they actually are. This blog breaks down the reality of mouth guard-induced sore throat, so let’s dive in.

Is Your Mouth Guard Actually Making You Sick?

Many people wonder, is sleeping with a mouth guard dangerous? In general, no, it is not dangerous to sleep with a night mouth guard. In fact, mouthguards are widely recommended by dentists for teeth grinding, jaw clenching, and even issues like tongue biting. They are designed to protect oral tissues, not harm them.

Problems begin when bacteria are allowed to accumulate.

A mouthguard sits in a warm, moist environment for hours. That environment is perfect for microbial growth. If the guard is not cleaned properly, saliva, plaque, food debris, and even respiratory bacteria can cling to it. When that same guard goes back into your mouth night after night, irritation and infection can follow.

So when people experience a mouth guard-related sore throat, it is rarely the plastic itself. It is what is living on the plastic.

Dirty Mouthguards and Sore Throats

One of the most common complaints linked to poor mouthguard hygiene is a persistent sore throat. This is where the primary keyword comes into play naturally. A mouth guard-related sore throat often develops because bacteria sitting on the guard come into prolonged contact with the soft tissues at the back of the mouth.

This is especially relevant after an illness.

If you recently had strep throat, a cold, or a sinus infection, your mouthguard can hold onto those pathogens. Reusing it without proper disinfection can reintroduce bacteria into your system. That is why many people search for how to clean a mouth guard after strep throat. The concern is valid.

After any throat infection, your mouthguard should be thoroughly disinfected or replaced. Otherwise, you may feel like you cannot shake the soreness, even though you finished your antibiotics.

Mouth Sores, Thrush, and Irritation from Mouth Guards

Another issue people notice is mouth sores. These sores are often blamed on pressure or friction, but hygiene again plays a big role. A dirty guard can cause:

• Small ulcers on the gums or cheeks
• Red, inflamed patches along the tongue
• White lesions linked to oral thrush
• A burning or raw sensation when swallowing

Thrush in particular is associated with fungal overgrowth. Candida thrives in damp environments. A mouthguard that is rinsed quickly and left in a closed case becomes an ideal home.

Sometimes the guard is not the only factor. Dry mouth, smoking, or recent antibiotic use can make you more vulnerable. Still, a contaminated appliance adds fuel to the fire.

Hygiene Is the Real Culprit

In most cases, the mouthguard is innocent. The routine around it is not. For example, people rinse it with water only and call it “clean”. Some store the guard wet in an airtight case. Other situations may include never disinfecting after illness, using hot water that warps the plastic and creates cracks, or even skipping cleaning because you are tired.

Over time, these habits add up. The guard starts to smell, feel slimy, or discolor. By then, bacteria have already built up.

The Problem of Poor Fit

A poorly fitting mouthguard can also cause problems. Constant rubbing creates pressure points. Micro-tears in the skin form. Bacteria then enter those areas more easily. Signs of poor fit include:

• Sharp edges digging into gums
• Jaw pain in the morning
• Guard slipping or falling out
• Increased mouth sores from night guard use

A custom-fit guard is usually more comfortable and safer than boil-and-bite options, especially for long-term wear.

What about Plastic Allergies?

In rare cases, hygiene is not the issue. Some people have sensitivities to certain plastics or acrylic materials. This can lead to redness, itching, or a burning sensation that does not improve even with proper cleaning.

If symptoms persist despite excellent hygiene, a material reaction could be the cause. A dentist can help identify this and recommend alternative materials.

Chewing, Tongue Biting, and Odd Mouthguard Habits

Not everyone uses a mouthguard the same way. Some people unconsciously chew on it during sleep or even while awake. Chewing a mouth guard can wear down the material and create tiny grooves. Those grooves trap bacteria more easily and are harder to clean.

A mouth guard for tongue biting can be incredibly helpful, but only if it fits well and stays clean. Otherwise, the guard can rub against the tongue repeatedly and worsen irritation.

Even learning how to put on a mouthguard correctly matters. Forcing it into place, touching it with unwashed hands, or dropping it on bathroom surfaces introduces more contaminants than most people realize.

How to Clean a Mouthguard Properly

Cleaning does not have to be complicated, but it does need to be consistent.

After every use, rinse your mouthguard with lukewarm water. Avoid hot water. It can distort the shape.

Use a soft toothbrush, separate from your regular one, and gently brush the guard. Mild, non-abrasive soap works better than toothpaste, which can be too harsh. This removes surface debris before it hardens.

Let the guard air dry completely before storing it. Moisture is the enemy.

Some people prefer household solutions. These can work, but caution is needed.

• White vinegar diluted with water can reduce bacteria. Do not soak too long.
• Hydrogen peroxide can disinfect but may degrade material over time.
• Baking soda helps with odor but is not a disinfectant on its own.

Avoid boiling water, bleach, or other harsh chemicals since they can damage the plastic. And damaged plastic becomes more irritating to the mouth.

Is It Ever Unsafe to Sleep with a Mouthguard?

The question comes up often. Is sleeping with a mouth guard dangerous? For most people, it is not. When the guard fits well and is kept clean, it protects teeth, muscles, and soft tissues.

Problems arise when the guard is cracked or warped, hygiene is neglected, the guard is used for unintended purposes like chewing food, or guards after illness are not properly disinfected. That’s why regular inspection matters. Sometimes, your mouthguard has just crossed its lifespan. If your guard smells bad even after cleaning, it may be time to replace it.

Can Mouthguards Do More than Protect?

Some people wonder whether oral appliances have other benefits. This curiosity leads to questions like can mouth guards straighten your teeth ? The answer is no. Mouthguards are not orthodontic tools; their only purpose is protection.

Finally, Are Mouthguards Making You Sick?

The answer is both yes and no. The mouthguard itself is totally safe. But when not properly maintained, the bacteria and fungi on it can make you sick.

Most mouthguard-related issues are preventable. A mouth guard-related sore throat, recurring thrush, or unexplained mouth irritation is usually not a sign that mouthguards are harmful. It is a sign that something in the routine needs to change.

Clean your guard properly. Disinfect it regularly. Replace it when it shows wear. Pay attention to fit and material. A mouthguard should protect your health, not compromise it. With the right care, it does exactly that.