The Durability Guard · For severe grinders
For the grinder who's done real damage.
3mm hard copolyester — the thickest guard we make. Built for severe bruxism where dental damage is already happening or a dentist has flagged serious concern.
Right for you if
- You have severe bruxism confirmed by a dentist with visible enamel damage or cracking
- You have worn through or cracked hard guards before
- You experience intense jaw pain, persistent headaches, or significant tooth sensitivity
vs. $650 dentist
Not sure this is right? Take the 2-minute quiz
What makes this guard right
3mm — maximum protection
The thickest guard in our range. Hard copolyester at 3mm provides a substantial barrier against severe grinding force — significantly more material between your teeth than any other Sentinel guard.
Built to outlast serious grinding
Medical-grade copolyester free from BPA, silicone, latex, MMA, and phthalates. Backed by a 1-year craftsmanship warranty — we stand behind what this guard is built to do.
Custom-fitted for all-night wear
At 3mm, precise fit matters more than any other guard type. Hand-finished to the exact contour of your impression so the guard seats correctly and stays in place regardless of grinding intensity.
What happens after you order
Place your order & email your scan
Choose your guard and check out. Then email the STL or PLY file from your dentist to info@sentinelmouthguards.com — we’ll confirm receipt and start manufacturing.
We finish your guard by hand
Your guard goes straight to manufacturing — no impression kit, no waiting. Our technicians hand-trim and polish it to the exact contour of your bite.
Protection arrives
Ships free with care instructions and a guard case to keep it safe between nights.
Right for you if
- You have severe bruxism confirmed by a dentist with visible enamel damage or cracking
- You have worn through or cracked hard guards before
- You experience intense jaw pain, persistent headaches, or significant tooth sensitivity
vs. $650 dentist
Not sure this is right? Take the 2-minute quiz
The Durability Guard
$199.75What's not in your guard
We use only dental-grade, FDA-compliant materials. Here's what you'll never find in a Sentinel guard.
Same material standards as your dentist
Sentinel's lab is FDA registered. Our finishing process meets the same standards your dentist's lab is held to — because we are one.
No leaching substances
You wear your guard 6–8 hours a night. Leaching is real — it happens when plasticisers migrate out of the material into your body. Every Sentinel material is selected specifically because it does not leach.
Not just BPA free — BPS free too
Many 'BPA free' products substitute BPA with BPS, which researchers believe may be equally harmful. Sentinel is free of both — and every other bisphenol compound.
Every guard is hand-finished in the USA by our dental technicians. No outsourcing. No exceptions.
The Sentinel Promise
The finishing process is what makes us confident enough to promise this. A guard that's hand-trimmed to your exact bite fits. And a guard that fits doesn't need a guarantee — but we offer one anyway.
100-Night Outcome Guarantee
Sleep on it for 100 nights. If you're not waking up better, return it. A $23 fee covers shipping and materials — everything else is refunded.
Three Attempts to Get It Right
Adjustments, remakes, and one complimentary redo impression kit in any combination. If the fit still isn't right after three attempts, we'll issue a refund minus a $23 fee to cover shipping and impression kit costs. Covered within your 100-night guarantee window.
1-Year Craftsmanship Warranty
Every guard is covered for one year against defects in materials and workmanship. We stand behind what we make.
Real Humans, Real Help
Talk to our dental technicians directly. No scripts, no runaround just expertise.
Customer Reviews
Denise Haselhuhn
Verified Buyer
I have had several mouth guards in the past and I have to say this is the best one I have ever had. It snaps into place and is a perfect fit. It is so comfortable that I don't even know I'm wearing it. I was able to get in on the 30% off sale and that made it very affordable. Sure beats the high cost from my dentist. I will definitely use this company again and would recommend highly.
Jennifer S
Verified Buyer
Just what I need at a great price. I’m a repeat customer because of the excellent customer service and affordable quality mouthguards . You all make sure it’s right which means so much when making a purchase . Thank you !!
Carolyn Angell
Verified Buyer
I wear my guard at night and when doing strenuous work. It helps a great deal with my clenching. I will still need surgery but it is helping.
Leticia Smith
Verified Buyer
Excellent quality retainer at a much lower price than my dentist.
Melody Sosa
Verified Buyer
I absolutely love this night guard! I had a small issue with the fit of my first one, but Sentinel immediately sent me a replacement that was perfect. The customer service was great and the product itself is excellent. This is actually my 4th night guard, and I’ve usually gotten them from the dentist for $200+and honestly, those weren’t even as good as this one. I paid a fraction of the price and received the best-quality night guard I’ve ever had. Highly recommend!
Kira Jeter Jeter
Verified Buyer
I have severe bruxism and unfortunately cracked the heavy duty night guard I got from my dentist. Because I cannot sleep without my night guard, I had to get a replacement in a hurry. I’ve ordered three guards from Sentinel over the years and have always been impressed with the customer service and quality so I knew that I could get a high quality replacement that is reasonably priced and would arrive quickly. The appliance fits perfectly and is very durable. Would definitely purchase again!
Adriana Amione
Verified Buyer
Very comfortable, use it every day and sometimes during the day. Easy and for a fraction of the cost! Very happy.
Connie Shieh
Verified Buyer
Durability Mouth Guard for Severe Teeth Grinding & Clenching
Chelsea Patarini
Verified Buyer
I've had two mouth guards from Sentinel and they've been fantastic. They're thicker than the mouth guard I had gotten from my dentist which I cracked within two months and cost me twice as much. My first Sentinel durability mouth guard lasted almost two years before my severe bruxism cracked it. My new one is going strong; it’s thick enough to protect my teeth and just as easy to sleep in as a standard mouth guard. And the customer service has been so helpful and courteous every time I've needed help.
Not quite right?
If a dentist hasn't flagged significant damage and you haven't worn through a hard guard before, the Hard Guard is the more appropriate starting point.
The Durability Guard
Current selection
The Hard Guard
More comfort