Retainer vs night guard

Page updated October 22, 2026.

A retainer and a night guard can look alike, two pieces of clear plastic that fit over your teeth, but they do different jobs. A retainer keeps your teeth where braces or aligners put them; a night guard protects your teeth from grinding and clenching while you sleep (Colgate). If you've just finished orthodontic treatment and you grind your teeth, you may be wondering whether you need one, the other or both. Here is how they compare, what each costs, and what to ask.

What each one does

A retainer maintains the position of your teeth after orthodontic treatment (Colgate). Teeth keep moving throughout life, and right after treatment there's a settling-in period when they're especially prone to moving back (AAO). Removable retainers are made of clear plastic or plastic and wire; fixed retainers are bonded behind the teeth (Colgate). See types of retainers.

A night guard is a mouth guard worn during sleep to protect the teeth from the effects of grinding and clenching (Cleveland Clinic). Grinding in your sleep can do more harm than grinding while awake, including worn, loose or cracked teeth, jaw pain and morning headaches (Cleveland Clinic). Night guards are made of soft or hard plastic and worn over the upper or lower teeth (Colgate).

There are three kinds: stock guards worn straight out of the box, boil-and-bite guards you shape at home, and custom guards a dentist makes to fit your teeth (Cleveland Clinic). A custom guard can last several years with proper care, while store-bought guards may need replacing a few times a year (Cleveland Clinic).

Retainer vs night guard side by side

Do you need both after braces?

Everyone who finishes braces or aligners needs a retainer; Cleveland Clinic says you'll likely wear a removable one full-time for at least four to six months and then at night for the rest of your life (Cleveland Clinic). You need a night guard only if you grind or clench your teeth, which a dentist can check (Colgate). Signs include jaw soreness, headaches or facial pain in the morning, and worn or cracked teeth (Cleveland Clinic).

If you grind in your sleep and also need to wear a retainer at night, you have a practical problem: both go over the teeth at the same time. Ask your orthodontist how to handle it rather than deciding on your own, because skipping a retainer for even a few days can let teeth shift significantly (AAO).

Can one replace the other?

We haven't found authoritative guidance from the AAO, the ADA or Cleveland Clinic saying a standard retainer is a substitute for a night guard, so we don't recommend relying on one that way. The two are designed for different jobs (Colgate). The reverse is also true: a night guard isn't designed to hold teeth in their corrected position, and the settling-in period after treatment is when teeth are most likely to move (AAO). If you grind, ask your orthodontist whether your retainer is suitable to wear while grinding, or whether you need a separate guard.

Cost of a retainer vs a night guard

Ranges: CareCredit data (CareCredit); averages: CareCredit's 2024 figures (CareCredit). Store-bought guards are cheaper but not as effective against grinding as custom ones, and custom guards usually cost more but last longer, often several years with proper care (Cleveland Clinic). Some dental insurers cover part or all of a custom-fitted guard, and you can use HSA money for custom and store-bought guards (Cleveland Clinic). More on retainer prices in retainer cost.

Caring for either one

• Rinse a night guard in cool water and clean it with a brush and soapy water after each use (Cleveland Clinic)
• Keep it away from extreme heat, such as direct sunlight or hot water (Cleveland Clinic)
• Clean your retainer as your orthodontist advises; see how to clean a retainer (AAO)

Questions to ask your orthodontist or dentist

• Do I grind or clench my teeth, and is there damage?
• Can my retainer be worn safely if I grind, or do I need a separate night guard?
• If I need both, how should I wear them at night?
• Will my dental plan or HSA pay for a custom night guard?