If you grind your teeth at night and play a contact sport, you will usually need two separate appliances. A night guard is a firm, fairly thin splint made to take hours of grinding and clenching during sleep. A sports mouthguard is a thicker, softer guard made to absorb a single hard knock to the mouth. Each does its own job well and the other's job poorly.
Night guards deal with slow, steady force
Grinding and clenching during sleep (sleep bruxism) is usually unconscious. Many people only find out when a dentist spots flattened or chipped teeth, or a partner hears the noise. Over time the forces can wear enamel, crack teeth and fillings, and leave the jaw muscles tight in the morning.
A night guard, also called an occlusal splint, covers the biting surfaces of one arch so the teeth grind against the guard instead of each other. Because it is worn for several hours every night, it has to be comfortable and stable, and thin enough not to prop the jaw open uncomfortably. Most are made from a hard or semi-hard acrylic or similar material.
Our article on bruxism and teeth grinding in adults covers causes and diagnosis, and grinding that comes with clicking or a sore jaw joint is discussed in TMJ and jaw clicking. If you grind and are thinking about veneers, see whether veneers suit people who grind.
Sports mouthguards deal with sudden impact
A sports mouthguard is worn for football codes, hockey, boxing, martial arts and any activity where a ball, stick, elbow or fall could hit the face. Its job is to spread and soften one sharp blow, which helps protect the teeth, lips, tongue and jaw. That calls for thicker, more cushioning material, especially over the front teeth and biting surfaces.
There is also some evidence beyond the teeth. A systematic review and meta-analysis in the British Journal of Sports Medicine (Eliason and colleagues, 2023) found fewer concussions among people wearing mouthguards in collision sports (incidence rate ratio 0.74). That is an association from pooled studies and should not be read as a promise that a mouthguard prevents concussion.
Side by side
| Night guard | Sports mouthguard | |
|---|---|---|
| Problem it addresses | Grinding and clenching during sleep | A sudden blow during sport |
| When it is worn | Overnight, for hours at a time | At training and games |
| Material | Firm, relatively thin | Softer, thicker and cushioning |
| Main protection | Tooth wear, cracked teeth and fillings, morning jaw tightness | Chipped or knocked-out teeth, cut lips and tongue, jaw injuries |
| Types available | Usually custom-made by a dentist | Custom-made, boil-and-bite or ready-made |
A soft sports guard can make night grinding worse
Sleeping in a sports mouthguard is uncomfortable for most people because of its bulk. There is also a more specific problem. In a small study in the Journal of the American Dental Association (Okeson, 1987), a hard occlusal splint reduced night-time jaw muscle activity in eight of ten people with bruxism, while a soft splint reduced it in only one and increased it in five. The study was small, but it suggests that soft, chewy material can invite more clenching rather than less.
The reverse swap does not work either. A night guard is thin and firm, so it offers little cushioning against a knock. Wearing one for contact sport leaves the teeth and lips without the protection a proper sports guard is designed to give.
Custom-made or over the counter
Both types come in two broad forms: boil-and-bite guards from a pharmacy or sports store, and custom guards made by a dentist from an impression or digital scan. Custom guards generally fit better and are more comfortable, which matters because a guard only helps if it is actually worn. For sports guards, the evidence that custom guards reduce injuries more than boil-and-bite guards is limited, so the main advantages are fit, comfort and the likelihood that a player keeps it in.
For grinding, a boil-and-bite guard is soft and can be a short-term stopgap at most, for the reasons above. A dentist can check whether grinding is the problem and make a guard that suits your bite.
What patients ask about guards
How can I tell if I grind at night?
Common signs are worn or flattened tooth edges, a tight or tired jaw on waking, morning headaches around the temples, or a partner hearing grinding. A dental check-up can confirm it.
Do children need a mouthguard for sport?
Children playing contact sports benefit from a well-fitted mouthguard just as adults do. Because children's mouths change as teeth come through, guards need to be checked and replaced as they grow.
How long does a night guard last?
It depends on how hard you grind and how well it is looked after. Bring it to your check-ups so the dentist can look for wear, cracks or changes in fit.
If you wake with a sore jaw, have noticed worn edges on your teeth, or need a guard for the coming season, a dentist can assess your teeth and bite and explain which guard suits you. See our current deals or read about general dentistry at Lumi Dental in Melrose Park. This article is general information and does not replace an individual dental assessment.
