A night guard is a removable dental appliance you wear over your teeth while you sleep to protect them from grinding and clenching. It creates a physical barrier between your upper and lower teeth, absorbing the force that would otherwise wear down enamel, crack teeth, or strain your jaw muscles. If you’ve been waking up with jaw pain, headaches, or your dentist has noticed your teeth are getting flatter, a night guard is one of the most common solutions.
How a Night Guard Works
When you grind or clench during sleep (a condition called bruxism), your jaw muscles can exert tremendous pressure on your teeth. Over time, that force wears down enamel, flattens the biting surfaces, and can even fracture teeth. A night guard sits between your upper and lower arches and distributes that force across the guard’s surface instead of concentrating it on individual teeth. It also slightly separates the jaws, which helps relax the muscles responsible for clenching and can reduce symptoms of TMJ disorders, including jaw pain, facial pain, and headaches.
Signs You Might Need One
Most people who grind their teeth at night don’t realize they’re doing it. The clues tend to show up indirectly. Frequent morning headaches, especially ones that feel like tension radiating from the temples or jaw, are one of the most common indicators. Worn or flattened teeth are another clear sign: if your teeth look shorter, more uneven, or have developed increased sensitivity, nighttime grinding is a likely cause. A sleeping partner who hears you grinding is also a reliable signal.
Your dentist can often spot the wear patterns during a routine exam before you notice symptoms yourself. Weakened enamel raises the risk of fractures and cavities, so catching it early matters.
Types of Night Guards
Night guards come in three broad categories based on how they’re made, and several material options within those categories.
By How They’re Made
- One-size-fits-all: Pre-formed guards sold at drugstores. They’re the cheapest option (typically $20 to $30) but offer the least protection and the loosest fit.
- Boil-and-bite: You soften these in hot water and bite into them to mold a rough impression of your teeth. The fit is better than a stock guard but still imprecise.
- Custom-fitted: Made from a professional impression of your teeth, either taken at a dental office or through a mail-order kit. A dentist-made guard, fabricated in a dental lab and verified for fit at your appointment, provides the most accurate and safest result. Prices for custom guards from a dentist typically run several hundred dollars and can approach $1,000, while mail-order versions fall somewhere in between.
By Material
- Soft guards are flexible and comfortable, making them a good starting point for mild grinding or people who primarily clench rather than grind. They’re the most affordable custom option but wear out the fastest.
- Hard acrylic guards are rigid and durable, built for moderate to severe grinding. They last significantly longer and offer the strongest protection, though they can feel bulky at first and take a few nights to get used to.
- Dual-laminate (hybrid) guards combine a soft inner layer against your teeth with a hard outer shell. They’re a good middle ground for moderate to severe grinders who want both comfort and durability, though they cost more than soft guards.
Over-the-Counter vs. Custom Guards
Over-the-counter guards are tempting because of the price, but fit quality matters more than most people expect. A guard that doesn’t sit precisely on your teeth can place uneven pressure across your bite, and that pressure can actually shift teeth over time. Research published in the British Dental Journal found that night guards purchased online were associated with tissue damage, tooth movement, and even choking hazards. If you have crowns, fillings, or implants, the risk is higher because shifted alignment can damage those restorations.
A custom guard from your dentist is molded to your exact bite, so the pressure is distributed evenly. Your dentist also checks whether the guard contacts all the teeth it should. For example, if only your back teeth touch the guard while your front teeth don’t, that uneven contact can worsen jaw symptoms rather than relieve them. A professional fitting catches those problems before you take the guard home.
What an Ill-Fitting Guard Can Do
The whole point of a night guard is to reduce strain, but a poorly fitting one can create new problems. Uneven pressure can cause teeth to shift, leading to changes in your bite alignment. When teeth move, it can trigger sensitivity, bleeding gums, and increased jaw pain. If you already have TMJ issues, a bad fit can aggravate them. A guard that presses into soft tissue causes soreness, swelling, and gum irritation.
If you notice any of these issues after starting to wear a guard, the fit likely needs adjustment. Custom guards from a dentist can be modified; over-the-counter guards generally cannot.
Cleaning and Care
Night guards sit in your mouth for hours in a warm, moist environment, which is ideal for bacterial growth. The American Dental Association recommends brushing your guard with a toothbrush and toothpaste every morning, the same way you’d brush your teeth. Get into all the grooves and crevices, then rinse with cool water. Hot water can warp the material, especially on softer guards.
After cleaning, store your guard in a vented case so it can dry completely between uses. A sealed container traps moisture and encourages bacteria and mold. Inspect the guard periodically for cracks, thinning, or rough spots. Soft guards may need replacing within a year or so for heavy grinders, while hard acrylic guards can last considerably longer with proper care.
What to Expect When You Start Wearing One
The first few nights with a night guard feel odd. You’ll be aware of it against your teeth, and you may produce more saliva than usual. Most people adjust within a week or two. Hard guards take the longest to get comfortable with, while soft guards feel more natural from the start. If you find yourself pulling the guard out in your sleep during those first nights, that’s normal and tends to stop as you get used to it.
A well-fitted guard shouldn’t cause pain. Mild pressure is expected initially, but sharp discomfort, sore spots on your gums, or a feeling that your bite is “off” when you remove the guard in the morning are all signs that something needs adjustment.