A night guard is a removable dental appliance you wear over your teeth while you sleep to protect them from grinding and clenching. Most people who search for this term are either waking up with jaw pain, have been told by a dentist that they’re grinding their teeth, or have noticed their enamel wearing down. Night guards work by creating a physical barrier between your upper and lower teeth, redistributing the force of your bite so no single tooth bears the brunt of the pressure.
How a Night Guard Protects Your Teeth
Teeth grinding, known clinically as bruxism, generates enormous force. Your jaw muscles can exert hundreds of pounds of pressure during sleep, and unlike daytime clenching, you have no conscious ability to stop it. Over time, this wears down enamel, cracks fillings, loosens crowns, and can cause chronic jaw pain or headaches.
A night guard doesn’t stop you from grinding. What it does is absorb and spread that force across the entire arch of teeth rather than letting it concentrate on a few contact points. This protects enamel from direct tooth-on-tooth friction, reduces strain on the jaw joint (the TMJ), and prevents damage to existing dental work like crowns or bridges. Think of it as a bumper: the grinding still happens, but the guard takes the punishment instead of your teeth.
Three Types of Night Guards
Night guards fall into three categories, and the differences matter more than you might expect.
Stock night guards are the cheapest option, typically $20 to $30 at a drugstore or online. They come in preset sizes with no customization at all. For most people, they’re too bulky, fit poorly, and are difficult to sleep in. They’re better than nothing in a pinch, but they’re not a long-term solution.
Boil-and-bite guards are made from a thermoplastic material. You heat them in hot water, bite down to create an impression, and let them cool. They cost roughly the same as stock guards and offer a slightly better fit, but the molding process is imprecise. They tend to be bulky, can shift during sleep, and wear down quickly if you grind moderately or severely. Even small inconsistencies in the fit can create uneven bite pressure, which reduces both protection and comfort.
Custom night guards are fabricated from a dental impression of your exact teeth, either taken at a dentist’s office or through an at-home impression kit. These fit precisely, stay in place overnight, and distribute bite force evenly. Custom guards can be made in soft, hybrid, or hard materials depending on how intensely you grind. They cost significantly more upfront (often a few hundred dollars through a dentist, sometimes more) but last longer and protect better. For anyone with moderate to severe grinding, custom is the practical choice.
Soft, Hard, or Hybrid Materials
The material your night guard is made from should match how hard you grind.
Soft guards are made from pliable, flexible material. They’re the most comfortable to get used to and work well for mild grinding or clenching. If you’re new to wearing a night guard, a soft one is often the easiest starting point. The tradeoff is durability: heavy grinders can chew through a soft guard in weeks.
Hard guards are fabricated from durable acrylic or rigid plastic. These are designed for advanced bruxism, TMJ symptoms, or people with extensive dental work like orthodontic restorations. They hold up under intense grinding force and maintain their shape over time. Some people find them uncomfortable initially, but most adjust within a week or two.
Dual-laminate (hybrid) guards combine a soft inner layer against the teeth with a hard outer shell. They’re especially effective for moderate grinders who find hard guards too rigid but need more strength than a soft guard provides. This middle-ground option balances comfort and protection well.
Upper Guard vs. Lower Guard
Most dentists default to an upper night guard because it tends to be more comfortable and doesn’t interfere with the tongue. However, upper guards are more likely to trigger a gag reflex in some people. If that’s an issue, a lower guard is typically the better option.
Your existing dental work also plays a role. If you have crowns, bridges, or implants on your upper teeth, a lower guard may be more suitable to avoid putting extra stress on that work. The reverse is also true. If you have significant restorations on either arch, a dentist can evaluate which placement makes the most sense for your specific mouth.
What They Cost
Night guards range from about $20 for a basic over-the-counter option to $1,000 or more for a professionally fitted custom guard from a dentist’s office. The wide range reflects real differences in materials, fit, and durability.
Over-the-counter and boil-and-bite guards keep costs low through mass production and cheaper materials, but they need replacing more frequently. Custom guards made through online dental labs (where you take impressions at home and mail them in) typically fall in the $100 to $200 range, offering a middle ground between drugstore guards and the full dental office price. Insurance sometimes covers part of the cost for a custom guard if your dentist documents medical necessity.
Caring for Your Night Guard
After each use, rinse the guard with cold water and gently scrub it with a soft toothbrush and mild soap. Avoid hot water, which can warp the material, especially with boil-and-bite and soft custom guards. For deeper cleaning, soak it occasionally in a denture cleaner or a mixture of water and baking soda to remove stains and odors.
Store it in a ventilated case, not a sealed plastic bag. Trapped moisture encourages bacterial growth. Keep it away from heat sources, including direct sunlight and car dashboards.
Most night guards should be replaced every six months to one year, or sooner if you notice visible wear: thinning spots, cracks, rough edges, or a fit that feels looser than it used to. Heavy grinders may go through guards faster, which is one reason material choice matters so much.
Potential Side Effects
Night guards are generally safe, but a poorly fitting guard can cause problems. The most significant risk is gradual changes to your bite. If the guard puts uneven pressure on certain teeth, minor shifting can occur over time, particularly in people with gum disease or weakened tooth structure. In rare cases, this can lead to an open bite that requires orthodontic correction.
Signs that your guard may be affecting your bite include new gaps between teeth, a feeling that your teeth don’t meet evenly when chewing, or new discomfort when biting down. These changes tend to develop slowly, so periodic dental checkups are useful for catching them early. A guard that was well-fitted to begin with and replaced on schedule poses minimal risk. The problems tend to come from over-the-counter guards with imprecise fits or from custom guards that have worn unevenly and haven’t been replaced.
Some people also experience increased saliva production, mild jaw soreness during the adjustment period, or difficulty sleeping for the first few nights. These issues typically resolve within a week as your mouth adapts to the appliance.