3mm Extreme Durability Hard Night Dental Guard


3mm Extreme Durability Hard Night Guard is for severe teeth grinding/jaw clenching (bruxism)

Made with dentist-grade hard acrylic-like material, your Sentinel Night Guard is non-flexible and solidly built. Safe for nightly use.
All of our night guard products are BPA, Silicon, Latex and Phthalate free.

  • Custom fit to your unique dental anatomy.
  • Non-flexible. Snaps into place for a perfect fit.
  • Relieves jaw pain, teeth pain, headaches, tooth sensitivity
  • Protects teeth from breakage, cracking, damage
  • Protects veneers, crowns, restorative dental work
  • Combats pain or tenderness of the temporomandibular joints
  • Easy “how to” instructions ensures consistent teeth impression results
  • Excellent durability and clarity.

What You’ll Get

  • A complete impression kit with instructions and prepaid return mailer
  • (1) custom night guard
  • Breathable retainer case
  • Fast all inclusive FREE shipping
  • 1 year warranty

Product Description

Premium 3mm Hard Dental Night Guard for Heavy Duty Teeth Grinding and/or Jaw Clenching

Made with dentist-grade hard acrylic-like material, your Sentinel Night Guard is non-flexible and built for durability. Safe for nightly use. All of our night guard products are BPA, Silicon, Latex and Phthalate free.

If for any reason, you experience pain or discomfort while using your product please discontinue use and contact us. Our commitment to you is 100% satisfaction. We provide free night guard adjustments.


Wake up Smiling or Your Money Back

The Sentinel Guarantee

Located in St. Petersburg, Florida, we specialize in night guard and mouth guard manufacturing.  All of our products are made in the USA by professional lab technicians with a combined dental experience of 20+ years. We guarantee:

    • 100% unconditional money back guarantee. We stand behind our products and will provide you with nothing less than our personal best from our long-standing team.
    • 90 Day Satisfaction Guarantee. If you don’t LOVE your new night guard (whether it’s a fit issue or comfort) let us know within 90 days. We'll either keep working to your satisfaction or you can opt for a refund in full.
    • 1 Year Warranty. If you break or grind through your night guard within 1 year of purchase, we’ll replace it for you free of charge.

Due to its thicker nature, we require that you take upper and lower teeth impressions for an even bite and to ensure proper occlusion.

If for any reason, you experience pain or discomfort while using your product please discontinue use and contact us. Our commitment to you is 100% satisfaction. We provide free night guard adjustments. 90 Day money back guarantee. Free all inclusive shipping in the USA.

.120 (3mm thickness) An added layer of thickness for extra durability. Ideal for severe nighttime grinding or jaw clenching. Suggested for heavy grinders.

Our Commitment To You

The Sentinel warranty and return policy is unlike any other. We stand by our products and will always work with you to your absolute satisfaction. This means if you are dissatisfied with your product for any reason, you can either contact Sentinel within 90 days for a full refund or opt to continue working with us until you get a great fitting guard. No hassle. No jumping through hoops. Our commitment to you is 100% satisfaction.

Get Fitted. Get Protected.

FREE SHIPPING IN THE U.S.A (International customers are responsible for shipping on return mailer).

Additional Information

Weight3 oz


Guard for


Product Reviews

  • Iris W.

    Not super comfy at first but really nice looking. I love that they are super low profile and the quality is great for the price. I totally recommend these.

  • Adam S.

    So first of all, this was super easy to take the impressions. All you have to do is mix the putty, place it in the tray and then slide the tray into the mouth. Push the putty up into the teeth and wait. It will get hard and may feel tough to pull out. Don’t panic. Just use more fingers to “pop” it off the teeth. A tip for putting the tray with putty into the mouth: have a timer on hand and stand in front of a mirror so you can see what you’re doing. It took me two attempts. This may sound confusing, but make sense when you are assembling it.

    Okay! The actual guard itself! It has really nice material & the shaping is well done. One piece in the front was a bit loose, but otherwise feels great. I’ve never had real quality guards so I can’t really compare it, but it seems sturdy.. I guess time will tell. I do wish the guard was a different color (it’s clear) because I just don’t want to misplace it..Now, the biggest concern for me is the comfort and they got that right. 5 stars!

  • Erin Chapman

    Great for teeth grinders! I needed a mouth guard for sleeping that wouldn’t be too big and uncomfortable that I take it out during the night. Wanted one just for the top teeth and less bulky than the one I got from my dentist. Tried the OTC ones and I just remove them during the night, or they cause my teeth and jaw to hurt by morning due to the imperfect alignment. THIS ONE IS PERFECT. I read some reviews that said it was difficult to take the impression, but I watched the YouTube video and got it perfect the first try. Follow the instructions, use a mirror to place it and you won’t have a problem. It is not necessary to bite down hard into the plastic when taking the impression. Really just stay focused on getting a good, even impression. Seems like a lot for a little piece of plastic, but my dentist wanted to make me one for $800, so this was a much better deal. And best part, woke up without a headache for the first time in years. Cheers!

  • Jaycin Diaz

    MIX FAST! I mixed my putty too slow and the putty hardened before I was ready. I contacted the sentinel team and they sent me new putty. 2nd time around went much better but mix quickly because the putty will harden and you will not be able to get your teeth into it! End product fit great. I’ve been wearing it nightly and have seen a significant reduction in my jaw pain and morning headaches.

  • Charles C.

    I have a horrible case of bruxism (night teeth grinding) and bought this to help me because most products store bought ones are so thick they trigger my gag reflex. Because of the slim size and unique material of this night guard, it has been helping me finally get a good nights’ sleep.This is different than most other ones I’ve tried. Thanks!

  • Nicholas Cook

    So glad they started offering the 3mm night guard. I grind so badly that my teeth were wearing through the 2mm hard guard. I’ve had this one for 8 months now and so far so good!

  • Sentinel customer

    Excellent product. Works exactly as advertised. I can breath easier, drink and even speak clearly. But even better is that it took us 3 attempts to mold the impression correctly and each time, Sentinel was patient with us and helped us until we got it right. Remarkable product. And let me add that my wife and I have had many of these from the dentist over the years. These are just as durable.

  • A. Valenzuela

    I was looking for a safe mouth guard and researched heavily. I asked several companies what was in their materials that they use and most were either vague or didn’t respond. This was the only company that I found that was willing to be transparent about the products they use.
    I did confirm that the plastic is BPA free which was my main concern. The night guard took many nights to get used to but I finally enjoy wearing it. Thank you for being a reputable company. -Alicia

  • Melissa

    The product is fine but ultimately didn’t work for what I needed it for. Resulted in a refund. Refund process was easy.

  • Shana Odlen

    Spoke with Alexandra and she was very helpful and recommend that a ask for some extra putty!!

  • Mel H

    I got this for my elderly mother because she grinds her teeth VERY badly at night. Her mouth is tiny, and since the process requires taking a teeth impression, I asked for extra material. Getting the teeth impression on her tiny mouth was a little difficult but only because again, small mouth. It molds and hardens very quickly. in a matter of 2 minutes, so it may take a couple of tries to get it perfect, but overall it’s easy to use, and has easy directions. She says the mouth guard fits her well. A good purchase for the money in my opinion.

  • Jake B.

    Great product, not too bulky. Way less than the dentist. Happy customer!

Free Shipping

We ship to you a kit with everything you need from the molding trays and putty, to the prepaid packaging the return it to us.

90 day guarantee

Try it out! If you’re not satisfied, you can always return the Mouthguard within 90 days for a full refund.

Save 20%

By entering coupon code "big spender", you save 20% on orders over $200.