Night guard wear & heavy grinding
Updated September 1, 2026
If you've worn a hole through a night guard, flattened it, thinned out one area, or replaced several guards much sooner than expected, the wear pattern may be giving you useful information about your grinding, clenching, and the type of protection you're using.
Repeatedly wearing through a night guard can happen when grinding or clenching forces are concentrated in the same areas night after night. It may also mean the material, thickness, or design isn't well matched to your particular wear pattern. Some surface marks are expected; repeatedly developing deep grooves, severe thinning, tears, or holes deserves a closer look.
Prefer to watch?
A closer look at why some people wear through their night guards faster than others.
Is it normal to have wear marks on a night guard?
Some wear can be expected. A night guard is positioned between the upper and lower teeth, so repeated clenching and grinding can leave contact marks, shallow grooves, polished areas, or indentations over time.
A mark on your guard does not automatically mean anything is wrong, and the appearance of a guard by itself cannot tell you exactly how severe your bruxism is.
What is more useful is the pattern and progression of the wear.
May simply show where the opposing teeth contact the guard.
Suggest repeated force is being concentrated in specific areas.
Mean the appliance has sustained more significant structural wear and should be evaluated.
If your main question is about ordinary marks, scratches, white areas, or indentations rather than rapid destruction of the appliance, see our dedicated guide: Why Does My Night Guard Have Marks on It?
Grinding and clenching can wear a guard differently
Bruxism includes both grinding and clenching. The National Institute of Dental and Craniofacial Research defines bruxism as grinding, clenching, or gnashing the teeth, and notes that it can occur while awake or during sleep.
Movement across the guard
Side-to-side or forward jaw movement can create tracks, flattened areas, polishing, or grooves where the opposing teeth repeatedly move across the material.
Pressure in one area
Sustained squeezing may create concentrated pressure without obvious side-to-side scratch marks. Over time, certain areas may compress, flatten, thin, or become more vulnerable to damage.
You may do one, the other, or both—and because sleep bruxism happens while you're asleep, you may not be aware of the pattern yourself.
What are you actually seeing?
Why does my night guard keep wearing through?
There usually isn't one universal explanation. Repeated wear can reflect several factors working together.
The most useful question is not simply, “Why did this guard wear out?” but:
“Why is this part of this guard wearing this way in my mouth?”
Your grinding or clenching may be more intense than you realize
Sleep bruxism can occur without conscious awareness. Signs that may accompany more significant bruxism include worn or damaged teeth, jaw tightness or soreness, headaches, and facial discomfort.
A mouth guard creates a barrier between the teeth so the appliance takes the contact instead of allowing tooth-to-tooth wear. It does not necessarily stop the underlying bruxism.
The same area may be taking most of the load
Night guards do not always wear evenly.
If one tooth or one region repeatedly contacts the appliance with greater force, you may see localized thinning or a hole in that area while the rest of the guard still looks relatively intact.
Dental work, tooth position, missing teeth, changes in the bite, and the way your jaw moves can all affect where contact occurs. A dentist can evaluate your bite and the appliance if one area repeatedly fails.
Your guard material may not match your wear pattern
Different night guard materials behave differently under repeated loading.
In our lab, we often see flexible materials chosen for comfort by people who later discover that they grind or clench more aggressively than expected. In those cases, a different material or design may be worth considering.
Thickness may matter
If all other factors are similar, a thicker appliance simply provides more material in the area being worn.
That does not mean “thicker is always better.” More thickness can also change how an appliance feels in the mouth, so the appropriate design depends on the person, bite, material, comfort, and grinding pattern.
Your bruxism pattern may have changed
Grinding intensity is not necessarily identical throughout your life.
Stress and emotional distress are among the factors associated with bruxism. Caffeine, alcohol, smoking, and certain medications can also play a role.
If a guard that previously held up well suddenly begins wearing much faster, it may be worth considering whether anything else has changed—and mentioning a significant change to your dentist or healthcare professional.
Choosing the next guard
Should you switch to a harder or thicker night guard?
Sometimes—but repeated wear doesn't automatically mean everyone should move to the hardest or thickest appliance available.
At Sentinel, our main night guard constructions include:
A soft, flexible option intended for people who prioritize cushioning and comfort.
Combines a softer 1 mm inner layer with a 1 mm copolyester outer layer.
A firm thermoformed option for people who prefer a hard guard construction.
A thicker hard option designed for people who need more material for repeated heavy wear.
If you have repeatedly worn through softer or thinner guards, it may be reasonable to discuss whether a different construction makes more sense for your pattern.
You can compare the options in our Complete Guide to Custom Night Guards .
What if I'm wearing a hole through my guard?
A true hole is different from an ordinary bite mark.
Once the material has worn completely through, that part of the guard no longer provides the same barrier between the opposing teeth. If you repeatedly develop holes in roughly the same place, save the worn appliance and show it to your dentist or guard manufacturer—it may offer useful information about the location of the repeated contact.
If the guard is also cracked, split, has a sharp edge, or has a piece missing, see our separate guide: My Night Guard Broke: What Should I Do?
How quickly is “too quickly” to wear through a night guard?
There isn't one lifespan that applies to every night guard or every person.
Material, thickness, grinding pattern, frequency of wear, care, and individual bite forces all influence how long an appliance remains functional.
Rather than repeat an entire lifespan chart here, we've covered that question separately in: How Long Do Dental Night Guards Last?
The bigger concern on this page is repeated premature wear. If you're replacing the same type of guard over and over because it develops the same deep groove, thin spot, or hole, that pattern is worth investigating rather than automatically ordering an identical replacement each time.
A note from our lab
Wear patterns can tell a story
After making custom night guards for many different types of grinders and clenchers, one thing we pay close attention to is where an appliance is wearing—not simply whether it has marks.
A localized thin area, repeated hole, broad flattened section, or deep groove can provide clues about where contact is occurring and how the appliance is being loaded.
That doesn't allow us to diagnose the cause of someone's bruxism from a night guard alone. But it can help guide practical questions about material, thickness, fit, and whether a different guard design should be considered.
If you replace a heavily worn guard, it can be useful to keep the old one long enough to compare the wear pattern with the replacement.
When should you involve your dentist?
Repeated night guard wear is especially worth discussing with a dentist if you also notice:
- New tooth sensitivity or pain
- Chipped, cracked, flattened, or increasingly worn teeth
- Morning jaw pain or persistent jaw tightness
- Frequent headaches or facial pain
- A noticeable change in your bite
- A sudden increase in grinding or clenching
- Multiple guards failing unusually quickly
If you also have significant snoring, witnessed pauses in breathing during sleep, or pronounced daytime sleepiness, mention those symptoms to a healthcare professional as well. Sleep bruxism can occur alongside sleep disorders such as obstructive sleep apnea, although the relationship is complex and one should not be assumed to directly cause the other.
So what should you do next?
Frequently asked questions
Why do I keep grinding through my night guard?
Repeated wear can occur when grinding or clenching places significant or highly concentrated forces on the same areas of the appliance. Material, thickness, fit, bite contact, and changes in your bruxism pattern can also influence how quickly a guard wears.
Does wearing through my night guard mean my grinding is severe?
Not necessarily. Rapid or repeated wear may suggest substantial grinding or clenching, but the appearance of a night guard alone cannot measure bruxism severity. Material, thickness, bite contact, and design also affect wear.
Are bite marks on a night guard normal?
Some contact marks or shallow indentations can occur with regular use. Deep grooves, severe thinning, cracks, tears, or holes are more significant forms of wear and should be evaluated separately.
Can clenching wear through a night guard even if I don't grind?
Yes. Bruxism includes both grinding and clenching. Sustained clenching can concentrate force in particular areas even without obvious side-to-side grinding marks.
Should I switch to a hard night guard if I keep wearing through soft ones?
It may be worth considering a different material or thickness, but there is no single guard construction that is best for everyone. Comfort, bite, wear pattern, grinding behavior, and dental history all matter. Your dentist or guard provider can help you compare options.
Does a night guard stop teeth grinding?
A night guard is primarily used to separate and protect the teeth from damage caused by grinding and clenching. It should not be viewed as a guaranteed way to eliminate the underlying bruxism.
What should I do if I wore a hole through my night guard?
A hole means the material has worn completely through in that area. Have the appliance evaluated, especially if the same location repeatedly fails. If there are also cracks, sharp edges, missing pieces, or a major change in fit, stop treating it as ordinary wear and have the guard assessed for replacement.
Dental & medical references
- National Institute of Dental and Craniofacial Research: Bruxism
- Cleveland Clinic: Bruxism (Teeth Grinding)
- Mayo Clinic: Teeth Grinding — Symptoms and Causes
This article is for educational purposes only and is not intended to diagnose or treat bruxism or replace individualized dental or medical advice.