What is the difference between a night guard, a splint and a retainer

Perhaps you've been told you need a night guard, a splint or a retainer, and you're not entirely sure why, or whether it'll actually fix what's bothering you. That confusion is fair: These three appliances look alike and get talked about interchangeably, but they don't do the same job.

A night guard protects your teeth from grinding, a splint treats jaw joint problems and a retainer holds your teeth in place after orthodontic treatment. Using the wrong one won't just fail to help; it can actually make things worse. 

What you’ll learn in this article: 

• A night guard protects your teeth from grinding damage, but it won't treat jaw pain or hold teeth in place after braces. 

• An occlusal splint is a therapeutic device prescribed for TMJ disorders; it's not the same as a drugstore night guard. 

• A retainer is designed to hold your teeth in position after orthodontic treatment, not to absorb grinding force. 

Using the wrong appliance for your condition can delay relief or cause new problems. Schedule an appointment with an Aspen Dental provider to find out which one you actually need. 

What is a night guard? 

A night guard is made to protect your teeth from grinding and clenching. Dental providers call this bruxism. The National Institute of Dental and Craniofacial Research (NIDCR) defines bruxism as a condition where a person grinds, clenches or gnashes their teeth. It can happen while you're awake or asleep, so you may not even know you do it.¹

Bruxism symptoms 

The NIDCR says severe bruxism can lead to damaged teeth due to the force grinding puts on them.¹ It can also cause jaw pain and headaches. Over time it can also cause cracks and chips, wear down the biting surface and make your teeth sensitive. 

How a night guard helps 

A night guard sits between your upper and lower teeth, cushioning them and preventing damage from grinding or clenching. It won't stop the grinding itself, but it protects your teeth while it happens. You can buy one at a drugstore, but a dental provider-made guard fits your teeth exactly, which makes a real difference in comfort and protection. 

What is an occlusal splint? 

An occlusal splint looks similar to a night guard, but it serves a different purpose. It's a clinical tool used to treat problems with your jaw joint and bite. Dental providers often use splints to manage temporomandibular joint (TMJ) disorders, which affect the joint connecting your jaw to your skull. 

When that joint isn't working well, it can cause pain, clicking, locking and headaches. MedlinePlus notes that intraoral appliances for jaw disorders include oral splints and mouth guards.²

How a splint works 

A splint is custom-made by a dental provider. It is carefully designed to hold your jaw in a specific position. That position takes pressure off the joint and lets it heal. 

A splint may also help your dental provider figure out where your bite problems are coming from. It is a diagnostic and treatment tool, not just a protector. MedlinePlus says a dental appliance should not be designed to permanently change your bite.² That's worth asking about before you start wearing one. 

Night guard vs. splint 

A night guard is mainly protective and guards your teeth from wear. A splint is therapeutic, which means it’s meant to change how your jaw sits and functions. They may look similar, but they are built for different needs. 

A store-bought night guard should never be used in place of a prescribed splint. The fit and design matter for treatment to work. 

What is a retainer? 

A retainer holds your teeth in place after orthodontic treatment. Braces or clear aligners move your teeth into a new position, and a retainer keeps them there. 

Your teeth have a natural tendency to drift back. Wearing your retainer as directed stops that from happening. 

Why a retainer isn't a substitute 

A retainer is designed to hold your teeth in position, not to protect them or absorb pressure. It won't guard against grinding, treat TMJ pain or handle bite force the way a night guard or splint can. If you grind your teeth and wear only a retainer at night, you risk cracking or warping it, and your teeth stay unprotected. 

Why you can't swap one for another 

These three appliances aren't versions of the same thing. Each is built for a specific job, like a spatula, a whisk and a strainer. They belong in the same drawer, but you can't swap one in for another. 

A retainer used as a night guard won't protect your teeth from grinding. A night guard used as a splint won't treat your jaw joint, and might even make things worse. A splint used as a retainer may not hold your teeth in place. 

Your dental provider picks the right tool based on what's actually happening in your mouth. 

How to find out which one you need 

If you wake up with jaw soreness, headaches or sensitive teeth, talk to your dental provider. These can be signs of bruxism. Your dental provider can check for wear on your teeth and ask about your symptoms. 

If you've had braces or aligners, ask your dental provider about retainer wear. It's a long-term commitment, and it's worth keeping up with. 

If you have jaw pain, clicking or trouble opening your mouth wide, your dental provider can check your jaw joint and talk with you about whether a splint might help. 

If you grind your teeth and have had orthodontic treatment, talk to your dental provider. They can determine whether you need more than one appliance and recommend a plan that addresses both needs. 

What is the difference between a night guard, a splint and a retainer? FAQs 

Still have questions about the difference between these dental devices? These answers cover a few common questions. 

Can a dentist tell if I grind my teeth even if I don't notice it? 

Yes. Your dental provider looks for signs at your regular checkups. Worn-down biting surfaces, small chips and flattened tooth tips are all clues. Your dental provider may also ask about morning headaches or jaw soreness. You don't have to catch yourself grinding for a dental provider to spot it. 

Can I wear a night guard if I've had braces? 

You can, but your dental provider needs to know both things. A night guard made after orthodontic treatment should fit your current teeth. Your dental provider will make sure it doesn't interfere with your retainer schedule. 

Will my insurance cover any of these appliances? 

Coverage varies. Dental insurance may cover part of the cost for a night guard or splint, especially if there's documented need. Retainers after orthodontic care are sometimes included in treatment plans. It's worth calling your insurance provider to ask what's covered before your appointment. 

What if I lost my retainer and my teeth feel like they've shifted? 

Don't wait. See your dental provider as soon as you can. Small shifts may be correctable. The longer you wait, the more your teeth can move. Your dental provider will check what's happened and talk through your options. 

Sources 

¹ National Institute of Dental and Craniofacial Research: “Bruxism.” https://www.nidcr.nih.gov/health-info/bruxism 

² National Library of Medicine, MedlinePlus: “Temporomandibular Disorders.” https://medlineplus.gov/temporomandibulardisorders.html